Scholarly article on topic 'Dietary fibre and the prevention of chronic disease - should health professionals be doing more to raise awareness?'

Dietary fibre and the prevention of chronic disease - should health professionals be doing more to raise awareness? Academic research paper on "Health sciences"

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Academic research paper on topic "Dietary fibre and the prevention of chronic disease - should health professionals be doing more to raise awareness?"

Nutrition Bulletin

ORIGINAL ARTICLE DOI: IO.IIII/nbu.12212

Dietary fibre and the prevention of chronic disease - should health professionals be doing more to raise awareness?

S. Lockyer, A. Spiro and S. Stanner

British Nutrition Foundation, London, UK

Abstract The recent report on Carbohydrates and Health by the Scientific Advisory

Committee on Nutrition concluded that a high fibre intake is associated with reduced risk of a number of significant chronic diseases in the UK, although further studies are needed to fully elucidate the precise mechanisms involved. New recommendations have been set for adults and younger people but dietary surveys suggest that intakes are currently well below these targets, reflecting low consumption of fibre-containing foods such as fruit, vegetables, nuts and seeds and high-fibre/wholegrain starchy foods. A wide number of interrelated barriers to increasing intakes have been purported. These include a lack of awareness of the health benefits of fibre; relatively little interest amongst the media compared with other nutrients (e.g. sugars); perceived high cost of fruit and vegetables; perceptions of starchy carbohydrates as unhealthy; taste preferences for refined grains; lack of a specific dietary recommendation or national awareness campaign for fibre or wholegrain intake; no general permitted (European Food Safety Authority approved) health claims for fibre and wholegrain; and a lack of mandatory labelling of fibre values on packaging. Health professionals have an important role in giving dietary advice, including the promotion of dietary fibre. However, as well as limited time during appointments to discuss diet and lifestyle issues, the level of confidence and competency in delivering such advice may be lacking amongst some health professionals. Current knowledge and awareness of the key messages around dietary fibre amongst health professionals have been poorly studied. A small online survey of UK practice nurses (n = 50) recently commissioned by the British Nutrition Foundation suggested that, although the benefits of dietary fibre intake in relation to cardiovascular disease, type 2 diabetes and colorectal cancer are largely acknowledged, the perceived importance of fibre for patient health is lower than other nutrients such as fat and sugars. One in five nurses reported not having adequate skills or knowledge to offer dietary advice and one in four said they sometimes lacked the confidence to give dietary advice to their patients. In view of the evidence for the health benefits for dietary fibre, there is a need to increase the importance that health professionals place on communicating ways to boost intakes amongst their

Correspondence: Dr. Stacey Lockyer, Nutrition Scientist, British Nutrition Foundation, Imperial House, 15-19 Kingsway, London, WC2B 6UN, UK.

E-mail: S.Lockyer@nutrition.org.uk

©2016 The Authors. Nutrition Bulletin published by John Wiley & Sons Ltd on behalf of British Nutrition Foundation. 1

This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

patients. Easy to access nutrition training for health professionals would help to support this objective.

Keywords: barriers, dietary fibre, health professionals, starchy carbohydrates, wholegrain

The health benefits of dietary fibre with regard to gastrointestinal or digestive health have long been recognised. A protective effect for colorectal cancer was hypothesised in the 1970s when low rates of the disease were observed in Africa (Burkitt 1971). Evidence of increased faecal weight with fibre intake, and the observation that there tended to be a lower incidence of bowel disease in populations with higher faecal weights, was used as the basis of the UK Dietary Reference Value (DRV) for fibre set by the Committee on Medical Aspects of Food Policy (COMA) in 1991. More recently, the UK's Scientific Advisory Committee on Nutrition (SACN) reviewed the wealth of evidence published in the subsequent 25 years, describing its findings in the report Carbohydrates and Health (SACN 2015). The body of evidence from prospective cohort studies suggests that increased intakes of total dietary fibre, and particularly cereal fibre and wholegrains, are associated with a lower risk of cardio-metabolic disease and colorectal cancer (Table 1).

Following this report, the UK DRV for fibre intake was raised from 18 g of non-starch polysaccharide (NSP) fibre (or around 24 g of AOAC fibre1) per day to 30 g of AOAC fibre per day for those aged 16 years and over. This is higher than that set by the European Food Safety Authority (EFSA) and in Ireland, but is comparable with recommended intakes in other nations (Table 2).

Chronic diseases such as cardiovascular disease (CVD), type 2 diabetes and colorectal cancer are major causes of mortality and morbidity in the UK. CVD is responsible for 27% of deaths (155 000 per year, 26% of which are under the age of 75 years), whilst an estimated 7 million people in the UK are living with the condition (BHF 2016). In 2013, 6% of the adult population had diagnosed diabetes, with an estimated 90% being type 2 diabetes (Diabetes UK

1The previous Dietary Reference Value was for non-starch polysaccharides (NSP), defined by the Englyst method. AOAC fibre includes all carbohydrates that are neither digested nor absorbed in the small intestine and have a degree of polymerisation of three monomeric units or more (i.e. non-starch polysaccharides, non-digestible oligosaccharides, resistant starch and polydextrose), plus lignin.

Table 1 Relative risk of disease with every 7 g/day increase in fibre consumption from prospective studies

Cardiovascular disease RR 0.91; 95% CI0.88, 0.94 P < 0.001 10 studies

Coronary events RR 0.91; 95% CI0.87, 0.94 P < 0.001 1 3 studies

Stroke RR 0.93; 95% CI0.88, 0.98 P = 0.002 7 studies

Type 2 diabetes RR 0.94; 95% CI0.90, 0.97 P = 0.001 1 3 studies

Colorectal cancer RR 0.92; 95% CI 0.87, 0.97 P = 0.002 1 3 studies

Adapted from SACN 2015.

Table 2 Recommendations for daily fibre intake in adults

Nation Recommendation Issuing body

Europe 25 g European Food Safety Authority

(EFSA)

Ireland 25 g Food Safety Authority of

Ireland (FSAI)

Nordic countries 25-35 g (3 g/MJ) The Nordic Council of Ministers

US 28 g (women), United States Department of

33.6 g (men) Agriculture (USDA)

(14 g/1000 kcal)

Australia and 25 g (women), National Health and Medical

New Zealand 30 g (men) Research Council (NHMRC)

Sources: EFSA Panel on Dietetic Products 2010a, USDA 2015, Food Safety Authority of Ireland 2011, The Nordic Council 2012, National Health and Medical Research Council 2006.

2014). Bowel cancer is the third most common cancer in both men and women and the second most common cause of cancer death in the UK after lung cancer (Cancer Research UK 2012).

Based on prospective studies (n = 10), SACN reported a 9% reduced risk of CVD with every 7 g of additional fibre intake (Table 1). Such studies suggest a greater protective effect in comparison with other dietary components often promoted for cardiovascular health. For example, the prospective US Women's Health Study (n = 39 876) reported a 17% reduction in CVD risk with each 10 g increment of daily intake of dietary fibre (RR 0.83; 95% CI 0.69, 1.01) (Liu et al. 2002) compared with a reduction in risk of 6% (RR 0.94; 95% CI 0.85, 1.02) with each additional daily serving of fruit and vegetables (Liu et al. 2000).

In its review of randomised controlled trials (RCTs), SACN found total dietary fibre, wheat fibre, other cereal fibres and fibre from specific fruit and vegetables to increase faecal mass and decrease intestinal transit times. Consumption of cereal fibre was found to reduce constipation (Table 3). On average, each gram of mixed dietary fibre increased faecal weight by 4 g and each gram of wheat fibre increased faecal weight by 4.8 g but there were insufficient studies to perform meta-analyses for the remaining fibre types. Recent reviews have supported this finding, concluding that there is good evidence that cereal fibres, particularly wheat fibre, increase faecal weight and speed up transit time. Studies also suggest fruit and vegetable fibre to have the same effects (de Vries et al. 2015, 2016). The general view is that dietary fibre, whether from cereals, fruit or vegetables, confers benefit on digestive health and should be included as part of a healthy diet.

Although SACN concluded that there was insufficient evidence from RCTs demonstrating beneficial effects of dietary fibre on cardiovascular risk markers such as blood pressure and fasting lipids, RCTs have shown higher intakes of oat bran and isolated p-glu-cans to lower total cholesterol, low-density lipoprotein (LDL)-cholesterol, triacylglycerol concentrations and blood pressure (Table 3).

Table 3 Summary of RCT-levelevidence presented in the SACN report describing biological effects of fibre consumption

Fibre type

Associated health benefits

Total dietary fibre

Wheat fibre

Non-wheat cereal fibre

Cereal fibre

Legume fibre

Oat bran and beta-glucans

Fruit and vegetable

fibre (evidence available for carrots, potatoes, prunes and citrus fruits)

Non-digestible oligosaccharides

Resistant starch

Polydextrose and polyols

Increases faecal mass

Decreases intestinal transit times

No impact on bodyweight or energy intake

Increases faecal mass

Decreases intestinal transit times

Increases faecal mass

Decreases intestinal transit times

Reduces constipation

Increases faecal weight

Improve lipids profiles

Lower blood pressure

Increases faecal mass

Decreases intestinal transit times

Improve lipid profiles

Increase faecal mass and bacterial content

Increases faecal mass and short chain

fatty acid content Increase faecal mass

Adapted from SACN 2015.

Prior to the new fibre DRVs, specific recommendations for fibre had not been set for children. However, concerns raised in the past that high-fibre diets in young children would lead to growth faltering and mineral imbalance in the developed world have not been well supported by research studies. Rather it has been suggested that, with the high rate of childhood obesity, increases in dietary fibre amongst those aged over 2 years may help to reduce energy intake. Although SACN reported a paucity of evidence in relation to the effects of dietary fibre intake in infants and children, the lack of an adverse effect in the highest infant and child fibre consumers supported the setting of a DRV for younger groups as a proportion of the adult DRV. The new DRVs are 25 g/day for adolescents aged 11-16 years, 20 g/day for children aged 5-11 years and 15 g/day for children aged 2-5 years. It is important to note that these recommendations are made providing children are able to achieve an adequate energy intake and are thriving.

The Eatwell Guide

In the light of the new fibre and free sugars recommendations, Public Health England (PHE) recently reviewed and launched a revised healthy eating model for the UK population. The Eatwell Guide (Fig. 1) depicts increased segment sizes for the starchy carbohydrates and fruit and vegetables groups compared with the previous version, the eatwell plate. Selection of beans, pulses and other sustainable plant proteins is also encouraged. Messages of relevance to dietary fibre within the accompanying booklet supporting the Eat-well Guide (PHE 2016b) are summarised in Table 4.

Fibre intake in the UK

Information about fibre intakes in the UK can be obtained from the National Diet and Nutrition Survey (NDNS) (2008/2009-2011/2012), which provides details of dietary intake from 6828 individuals aged 1.5 years and above, and the Family Food Survey 2014, a survey in which around 6000 households in the UK record their food and drink purchases. Although there are limitations in the data, these surveys currently provide the best national insight into the population's dietary intake.

From NDNS data, it is clear that average fibre intakes in all age groups are currently well below the recommendations, with adults, on average, needing to consume around 12 g more per day (see Table 5). The main foods contributing to fibre intake are cereals and

Figure 1 The Eatwell Guide (PHE 2016a).

cereal products (39% in adults), followed by fruit and vegetables (29%) and potatoes (13%) (see Fig. 2 and Tables 6 and 7 for a more detailed breakdown).

As the Eatwell Guide depicts, fruit and vegetables and starchy carbohydrates should form the most substantial parts of the UK diet. However, data from the Family Food Survey indicates that starchy carbohydrates make up only 19% and fruit and vegetables only 25% of food purchases (Defra 2015).

Consumption of fibre-containing foods

NDNS data indicates a current mean intake in adults of 13.7 g of NSP fibre (around 18 g of AOAC fibre) per day (12.8 g in women, 14.7 g in men), whilst previous NDNS data from 2000/2001 reported the mean intake in adults to be 13.9 g of NSP fibre (around 18.5 g of AOAC fibre) per day (12.6 g in women and 15.5 g in men). However, more recent data from the Family Food Survey suggests a larger decrease, with average intake in 2014 estimated as 14.2 g of NSP

fibre/day, 7% lower than in 2001 (Defra 2015). This reflects decreased sales of the major fibre-contributing foods (Fig. 3). Despite wholemeal bread now representing a larger proportion of total bread purchases, sales of all bread types have decreased and were 20% lower in 2014 compared with 2004. Potato purchases have also seen a substantial decline during this time period (18%). Similarly, falling trends in green vegetables have been observed over a long time period.

It is important to note that fibre-rich foods, such as cereal products, vegetables and potatoes, also make substantial contributions to micronutrient intakes in the UK (Bates et al. 2014). Wholegrain products, for example, are often more micronutrient dense than refined grain products (see Table 8).

Current intakes of wholegrain

Part of the emphasis on consumption of wholegrains in healthy eating guidelines relates to their higher fibre content. However, there are no specific

Table 4 Fibre messaging in the EatwellGuide

Food group

Messages that support an increase in fibre intake in the population

Fruit and vegetables

Potatoes, bread, rice, pasta and other starchy

carbohydrates

Beans, pulses, fish, eggs, meat and other proteins

Source: PHE 2016b.

Eat at least five portions of a variety of fruit and

vegetables every day Bulk out your meals with vegetables such as

grated carrot, mushrooms or peppers Remember to keep fruit in your bag as a convenient and healthy snack and frozen vegetables in your freezer so you do not run out Base your meals around starchy carbohydrate foods Choose wholegrain or higher fibre versions by purchasing wholewheat pasta, brown rice or simply leaving the skins on potatoes Wholegrain foods contain more fibre than white or refined starchy food, and often more of other nutrients

We also digest wholegrain food more slowly so it

can help us feel full for longer Wholegrain foods include wholemeal and

wholegrain breads, pitta and chapatti, wholewheat pasta, brown rice, wholegrain breakfast cereals and whole oats

You can also purchase high-fibre white versions of bread and pasta which will help to increase your fibre intake using a like-for-like substitute of your family favourites Eat more beans and pulses and lentils. These are good alternatives to meat because they are naturally very low in fat, and they are high in fibre, protein, and vitamins and minerals

Table 5 Comparison of current average daily intakes and recommended values for AOAC fibre

Age group

Average fibre intakes* (SACN recommendations**)

1.5-3 years 10.9 g (15 g)

4-10 years 14.8 g (20 g)

11-18 years 15.7 g (25 g)

19-64 years 1 8.2 g (30 g)

65 years and upwards 1 8.5 g (30 g)

et al. 2008), whilst US guidelines specify 48 g/day (USDHHS/USDA 2010). A recent analysis of NDNS data suggested median wholegrain intake in the UK to be 20 g/day for adults and 13 g/day for children/teenagers (Mann et al. 2015), with 18% of adults defined as non-consumers. In the UK (Mann et al. 2015) and elsewhere (Bellisle et al. 2014), there are socio-economic differences in wholegrain consumption, with higher intakes reported in those with higher education and income.

Breakfast consumption

Observational studies have demonstrated a number of benefits of eating breakfast including better overall dietary composition, higher intake of micronutrients and a higher intake of fibre (Deshmukh-Taskar et al. 2010; Barr et al. 2014; O'Neil et al. 2015). However, some 14% of children aged 5-15 years in the UK are reported to skip breakfast (Hoyland et al. 2012). Although the current NDNS has not reported patterns in breakfast consumption, a study looking at older data from the 2001 NDNS found that around 1 in 5 adults either skip breakfast completely or only have a drink (Gibson & Gunn 2011). This study also reported that average daily AOAC fibre intake was 14.6 g in breakfast skippers, 22.6 g in breakfast cereal consumers and 16.0 g in consumers of other breakfast items (Gibson & Gunn 2011).

Further studies have also demonstrated consumers of ready-to-eat breakfast cereals to have higher daily intakes of fibre and micronutrients than those who consume other foods for breakfast (Grieger & Cobiac 2012).

Those on a low income are more likely to skip breakfast (Keski-Rahkonen et al. 2003) and to consume breakfasts that do not comprise cereal, fruit or bread (Moore et al. 2007). Analysis of the 2003-2005 Low Income Diet and Nutrition Survey reported that average intakes of fibre were higher in adult breakfast cereal consumers vs. non-consumers but there were no differences in children.

Source: Bates et al. 2014.

*NSP values were multiplied by 1.33 to convert to AOAC.

**SACN fibre recommendations are for age groups 2-5, 5-11, 11-16 and

over 1 6 years.

recommendations on the amount of wholegrains that should be consumed each day in the UK. This is in contrast to some other areas of the world. In Denmark, for example, adults are recommended to consume at least 75 g of wholegrain per day (Mejborn

Current intakes of fruit and vegetables

Fruit and vegetables are important contributors to fibre intake in the UK. However, as a nation we are not meeting the 5 A DAY recommendation. Adults aged 19-64 years consume 4.1 portions of fruit and vegetables per day on average, with only 30% of both men and women achieving 5 A DAY (Bates et al. 2014). Mean consumption of fruit and vegetables for

Fruit and vegetables

(29%) Figure 2 Main foods contributing to fibre

intake in UK adults Source: Bates et al. 2014.

see Table 7

Table 6 Contribution of cerealproducts to fibre intakes in UK adults aged 19-64 years

Pasta, rice, pizza and other miscellaneous cereals 8%

Bread 19%

of which:

White bread 9%

(all types of bread and bread products made with

white wheat flour, not high fibre or multiseed)

Wholemeal bread 5%

(all types of bread and bread products made

with wholemeal flour)

Brown, granary and wheatgerm bread 4%

(includes high-fibre white bread)

Other breads 1%

Breakfast cereals 6%

of which:

High fibre 5%

(>4 g of NSP/I00g including porridge,

wheat biscuits, muesli and bran flakes) 1%

Other breakfast cereals

(<4 g of NSP/I00g including cornflakes and puffed rice)

Biscuits 3%

Buns, cakes, pastries and fruit pies 2%

Puddings 1%

Source: NDNS 2008/2009-2011/2012 combined (Bates et al. 2014). NSP, non-starch polysaccharide.

children aged 11-18 years was 3.0 portions/day for boys and 2.7 portions/day for girls, with only 9% of this age group meeting the 5 A DAY recommendation (Bates et al. 2014).

Table 7 Contribution of vegetables, fruit and potatoes to fibre intakes in UK adults aged 19-64 years

Vegetables 20%

of which:

Cooked vegetables 1 6%

Salad and raw vegetables 4%

Fruit 9%

Potatoes 12%

of which:

Chips, fried and roast potatoes and potato products 7%

Other potatoes, potato salads and dishes 5%

Source: NDNS 2008/2009-2011/2012 combined (Bates et al. 2014).

Fibre intake and dietary quality

Higher intakes of fibre tend to be associated with better diet quality overall. Fibre intake has been reported to be significantly higher amongst individuals achieving UK dietary targets for fat (<35% food energy), saturates (<11% food energy) and fruit and vegetables (Harland et al. 2012).

A study of 851 Irish adults looking at dietary patterns reported that those who consumed a 'prudent diet' (i.e. a diet that was lower in fat, with higher intakes of unrefined cereals, fish, poultry, low-fat dairy products and fruit and vegetables) had significantly higher intakes of fibre, as well as polyunsaturated fatty acids and vitamins C and E, and significantly lower intakes of total fat, saturates, monounsaturated

Potatoes

Vegetables

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Figure 3 Trends in UK purchases of potatoes, vegetables and bread 1974-2014 Source: Defra 2016.

fatty acids and cholesterol, when compared with the two other patterns identified, the 'traditional Irish diet' and the 'alcohol and convenience foods diet' (Villegas et al. 2004).

Achieving the new SACN recommendations for fibre

The average daily fibre intake that could be achieved by consuming 5 x 80 g portions of fruits and vegetables and 3 portions of starchy foods (including wholegrains) has been estimated as 21.7 g of AOAC fibre/ day (Hooper et al. 2015). In order to meet the new 30 g target for adults, additional fibre is required, possibly from high-fibre snacks (e.g. rye crispbreads, nuts and seeds), regular inclusion of pulses in meals, additional portions of fruit and vegetables (particularly those with higher fibre contents) and/or incorporation of new varieties of wholegrains into the diet (such as quinoa). Table 9 shows the fibre content of a variety of foods including starchy foods, breakfast items, fruit, vegetables and snacks, illustrating the variation between different options within each food category.

Considering current intakes, adjusting food choices in order to achieve the new fibre recommendation will be a challenge for the majority of individuals. For example, only 17% of adults in the UK consume nuts and/or seeds (Bates et al. 2014). However, the 30 g target is possible in the context of a healthy, balanced diet. As an example, the British Nutrition Foundation (BNF) developed a 7-day meal plan (BNF 2015) which provides an example of how the new fibre

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Table 9 Fibre content of selected foods per average portion size

AOAC fibre Applicable

content nutrition

Food (portion size) (g per portion) claims for fibre§

Wholemeal spaghetti (220 g, cooked) 9.2 High in fibre

Jacket potato with skin (180 g) 4.7 Source of fibre

White spaghetti (220 g, cooked) 3.7 -

Brown rice (180 g, cooked) 2.7 -

White long grain rice (180 g, cooked) 0.9 -

Mashed potato (60 g) 0.8 Source of fibre

Bran flakes (30 g) 7.4 High in fibre

Wheat biscuits breakfast cereal (2 3.9 High in fibre

biscuits, 40 g)

Fruit wheats (45 g)* 3.8 High in fibre

Muesli (Swiss style, no added sugar or 3.8 High in fibre

salt) (45 g)

Corn flakes (30 g) 0.8 -

Wholemeal toast (2 slices, 62 g) 5.1 High in fibre

White toast (2 slices, 54 g) 1.6 Source of fibre

Crumpet (toasted) (40 g) 1.2 Source of fibre

Red kidney beans (canned) (80 g)* 6.0 High in fibre

Chickpeas (canned) (80 g)* 4.2 High in fibre

Baked beans in tomato sauce (80 g) 3.9 High in fibre

Lentils (red split, cooked) (80 g)* 3.7 Source of fibre

Strawberries (80 g) 3.0 High in fibre

Pears (80 g) 2.2 High in fibre

Melon (cantaloupe) (80 g) 1.4 High in fibre

Bananas (80 g) 1.1 Source of fibre

Grapes (average of red and green) 1.0 Source of fibre

(80 g)

Oranges (80 g) 1.0 High in fibre

Apples (80 g) 1.0 Source of fibre

Peas (boiled) (80 g) 4.5 High in fibre

Green beans (boiled) (80 g) 3.3 High in fibre

Carrots (average of boiled and raw) 2.7 High in fibre

(80 g)

Sweetcorn (canned) (80 g) 2.5 High in fibre

Broccoli (boiled) (80 g) 2.2 High in fibre

Onions (average of raw, boiled and 2.0 High in fibre

fried) (80 g)

Rye crispbread (2 pieces, 20 g) 4.0 High in fibre

Almonds (25 g)* 2.5 High in fibre

Hummus (50 g) 2.5 Source of fibre

Hazelnuts (30 g) 2.1 High in fibre

Sunflower seeds (25 g)* 1.7 High in fibre

Pumpkin seeds (25 g)* 1.7 High in fibre

Trail mix (25 g) 1.3 Source of fibre

Peanut butter (smooth) (20 g) 1.3 High in fibre

Potato crisps (25 g) 1.1 Source of fibre

Chocolate caramel bar (50 g) 0.4 -

Jelly sweets (43 g) 0 -

Sources: FSA/IFR/PHE 2014, Food Portion Sizes (FSA 2006) and manufacturer's data.

*Average of own brand products from Sainsbur/s, Tesco, Asda and Morrison's (not currently available from McCance and Widdowson data). §'Source of fibre' can be used for foods which contain at least 3 g of fibre/ 100 g or 1.5 g of fibre/100 kcal. 'High in fibre' can be used for foods which contain at least 6 g of fibre/100 g or 3 g of fibre/100 kcal.

recommendations might be achieved, whilst also meeting other UK dietary and food-based recommendations, including no more than 5% of total energy from free sugars (SACN 2015). This plan included the consumption of over 8 portions (80 g or equivalent) of fruit and vegetables daily, high-fibre snacks (such as nuts and seeds) and all meals based on starchy foods, predominantly wholegrain. The cost of the plan was calculated using prices from two leading UK supermarkets, based on own brand products. This was estimated to be £37.24 per adult per week, which can be compared with the Family Food Survey average household spend on food of £41.97 per person per week (Defra 2015), although it is worth noting that the Family Food Survey spend reflects foods consumed both in and out of the home, whereas foods and drinks in the BNF plan were mostly home prepared.

Barriers to increasing fibre intakes

Labelling and EU health claims

Nutrition information on food labels must comply with a format set out within the EU Food Information for Consumers Regulations (European Commission 2011). However, mandatory values are only indicated for energy, fat, saturates, carbohydrates, sugars, protein and salt and not for fibre. The provision of front-of-pack information is voluntary but if provided must also meet the Regulations. This includes energy alone or energy plus fat, saturates, sugars and salt (Table 10). Percentage Reference Intakes (% RIs) can be given on a per 100 g/ml and/or per portion basis. Additional forms of expression are allowed if they meet the requirements set and the UK government have developed 'traffic light' colour-coded nutritional information.

Manufacturers can voluntarily claim foods as a 'source of fibre' if it contains at least 3 g of fibre per 100 g or

Table 10 Reference intakes (EU Food Information to Consumers Regulation Annex XIII part B) for front-of-pack nutrition labels

Energy (kJ) Energy (kcal) Fat

Saturates

Sugars

8400 2000 70 g 20 g 90 g 6g

Source: European Commission 201

1.5 g of fibre/100 kcal, or 'high in fibre' if it contains at least 6 g per 100 g or 3 g/100 kcal and where these claims are used, the fibre content must be provided in nutrition information on the back-of-pack (European Commission 2006). However, it is of note that fibre is not one of the four nutrients, in addition to energy, permitted on front-of-pack and it does not have a Reference Intake. Therefore, consumers have no direct information with regard to the proportion as a percentage of their daily fibre requirement that a portion of the food provides, although the actual grams of fibre per 100 g and per portion can be included on the back-of-pack.

According to market analysis by Mintel, the share of products making high-fibre claims grew in 2014 (Mintel 2015). However, research undertaken as part of the EU-funded CLYMBOL project looking at 400 randomly selected products in the UK, The Netherlands, Germany, Slovenia and Spain reported that only 9% of nutrition claims referred to fibre, whereas 35% referred to vitamins and minerals, 24% to the fat content and 12% to the sugar content (Hieke et al. 2016). The authors reported that of the UK products using an ingredient claim communicating the presence of an ingredient which is not a nutrient as defined in EU Regulation, most referred to fruit and vegetable content (e.g. 'one of your 5 A DAY') or wholegrain (e.g. 'with wholegrain').

The lack of mandatory labelling of dietary fibre makes it difficult for consumers to compare products and, furthermore, will not act to increase consumer awareness of fibre. Additionally, no general health claims for dietary fibre or wholegrains have been authorised except for specific types (mainly in relation to intestinal transit time and faecal bulk) (Table 11), making communication of health benefits to consumers difficult.

Table 11 European Food Safety Authority approved fibre claims

Sugar beet, wheat bran and oat and barley grain fibre contribute to an

increase in faecal bulk Rye fibre contributes to normal bowel function

Wheat bran fibre contributes to an acceleration of intestinal transit/Wheat bran fibre contributes to a reduction in intestinal transit time or Wheat bran fibre contributes to an increase in faecal bulk Regular consumption of beta-glucans (from oats or barley) contributes to

maintenance of normal blood cholesterol concentrations Replacing digestible starch with resistant starch induces a lower blood

glucose rise after a meal Consumption of arabinoxylan (produced from wheat endosperm) as part of a meal contributes to a reduction of the blood glucose rise after that meal

Sources: EFSA Panel on Dietetic Products 2009, 20I0b,c, 20lla,b,c,d,e,f,g,h.

Consumer understanding of the health benefits of fibre

Since the release of the SACN report, media focus has very much been on sugars, rather than on fibre. It is unclear as to whether the association between high-fibre diets and health benefits is recognised or understood by consumers. The importance consumers place on fibre-containing foods as part of a healthy, balanced diet is also unknown.

In the Food Standards Agency's (FSA) consumer attitudes survey, Food and You, of Scottish consumers (FSA 2014), only 26% thought starchy foods were very important to eat for a healthy lifestyle and 68% did not place starchy foods in the correct section of the eatwell plate (the food-based model used at that time) (PHE 2013). In comparison, 82% of respondents said that it was very important to eat fruit and vegetables and 71% knew that the recommended number of portions of fruit and vegetables to eat per day was five. A large proportion (75-93%) knew that frozen, canned, dried and juiced fruit and vegetables counted towards 5 A DAY; however, fewer consumers (around 60%) knew that baked beans and pulses count. Wor-ryingly, 20% of respondents thought that rice would count towards 5 A DAY and 17% thought that jam would count as a portion.

In a study carried out in Ireland for the FSA (Ipsos Mori 2012a), subjects reported that consumption of starchy carbohydrates should contribute about a quarter of their food intake rather than the third suggested by the eatwell plate (PHE 2013). Whilst bread, breakfast cereals, potatoes and baked products were popular amongst the respondents, foods such as pasta, rice and couscous seemed unfamiliar to older individuals, and knowledge of whether some foods are classed as starchy carbohydrates or not was poor. There was a perception that starchy carbohydrates were fattening, with many people stating that they were trying to cut down, for example by eliminating bread from their diet in order to lose weight and with participants citing information read in newspapers and celebrity magazines as the reason for doing this. Terms associated with starchy foods included 'stodgy', 'heavy', 'bloating' and also 'providing energy' and respondents described feeling tired after carbohydrate-rich meals. Bread, rice and pasta were perceived to be convenient as they have long shelf lives and can be prepared quickly and cheaply, although some noted that whole-grain breads can be more expensive than white versions which may be a barrier to consumption. Some older participants referred to bread and potatoes as being good sources of fibre or 'roughage' but in

general respondents were unaware of the nutrients that starchy carbohydrates provide, particularly micro-nutrients. The majority acknowledged that wholegrains were healthy and referred to advertisements they had seen for breakfast cereals which depict a link with better heart health. The same report gathered the views of a small number of health professionals and reported that, whilst dietitians were advising patients in line with government guidelines with regard to starchy carbohydrate consumption (i.e. that these should make up a third of every meal, as per the eatwell plate), other types of health professionals were unsure as to the quantity of starchy carbohydrates that should be consumed. Practice nurses had varied opinions but tended to advise patients to avoid bread and pasta, particularly those running obesity clinics.

In a similar focus group study carried out in Scotland (Ipsos Mori 2012b), the small group of health professionals interviewed felt that the message 'choose wholegrain varieties when you can' was confusing for consumers because it may encourage poor perception of refined carbohydrates amongst those not liking the taste of wholegrain foods. Concern was also expressed that potatoes are viewed by consumers as 'white' carbohydrates, as there is no wholegrain version (although potatoes in skins can contribute to dietary fibre intakes). Consumers held the view that if they ate larger amounts of starchy foods, it may encourage them to eat more of accompanying foods (e.g. fat spread) which would lead to higher intakes of fat and sugars. Overall, health professionals noted that additional messaging for consumers is required to reduce confusion and improve the perception of starchy foods.

Practical and behavioural barriers to fibre consumption

Barriers to increasing fibre intakes commonly cited by consumers are listed in Table 12.

Consumers often cite price as the most important factor determining product choice (Hawkes 2012). A recent

Table 12 Barriers to fibre consumption Price

Availability (e.g. less choice of wholemeal products, particularly when eating out)

Convenience (e.g. wholemeal pasta and brown rice take longer to cook than white varieties, preparation requirements for fruit and vegetables) Waste (e.g. rapid spoilage of fruit)

Too many competing foods (e.g. snack foods such as biscuits) Unwillingness to change existing food choices and habits.

Adapted from McKeown et о/. 2013 and Nicklas et о/. 2013.

UK study looking at resemblance of dietary patterns to the Dietary Approaches to Stop Hypertension (DASH) diet, which emphasises plant-based foods and wholegrains, found that diets which were the most aligned with this approach were 18% more expensive than those that were the least aligned (Monsivais et al. 2015). In addition, a UK analysis reported that healthier foods, such as fruit and vegetables, have been shown to be 3 times more expensive per calorie than those high in fat and/or sugar (Jones et al. 2014). Those on a low income report purchasing foods on special offer in supermarkets as a strategy for saving money (Hayter et al. 2015), but research has highlighted that these are more likely to be unhealthy products rather than fruit and vegetables (Khanom et al. 2015; PHE 2015). Ofcom data from 2003 reported 60% of food advertising spend in the UK was for confectionery and pre-prepared foods, whilst only 3% was on fresh fruit and vegetables (Ofcom 2003).

In terms of choice, the availability of wholegrain options when eating out is slowly increasing, with the appearance of wholemeal pizza bases and brown rice on some restaurant menus, but more could be done by the catering sector to offer a wider variety of high fibre choices. Pre-packed sandwiches made from wholemeal bread rather than white are more commonly available and some supermarkets have opted to remove confectionery from checkouts, replacing these with higher-fibre snacks such as nuts and dried fruit.

Diets which restrict intake of fibre

The BNF 7-day meal planner for adults suggests it is extremely difficult to consume 30 g of fibre/day without basing meals on starchy carbohydrates (BNF 2015).

Around one in 100 people in the UK has coeliac disease (NHS Choices 2014) and needs to avoid gluten (present in products made from wheat, rye and barley) for medical reasons. Others avoid gluten due to a self-diagnosed intolerance or a perceived health benefit of a gluten-free diet. Furthermore, the popularity of low-carbohydrate diets has resulted in some individuals choosing to avoid or reduce their consumption of potatoes, as well as grain products (Nicklas et al. 2013). Low consumption of carbohydrates has been associated with lower fibre and wholegrain intakes (Oh et al. 2005; Fung et al. 2010).

Impact of initiatives to promote high-fibre/ wholegrain foods internationally

In order to increase fibre intakes, interventions can focus on fibre per se or the promotion of high-fibre

foods such as fruit and vegetables and wholegrains. Campaigns to increase fruit and vegetable intake have been prominent both in the UK and internationally. The UK 5 A DAY scheme, launched in 2003, aimed to increase awareness and consumption of fruit and vegetables to 5 x 80 g portions/day for everyone by 2015. The initiative included the National School Fruit Scheme, an advertising campaign, communitylevel activities such as 'Cook and Eat' and 'Sow and Grow' schemes, partnership with industry to allow logos to be used on food labels displaying how many portions of fruit and vegetables products contain, and the incorporation of the 5 A DAY message into larger public health schemes such as Change4Life. The 5 A DAY messages on the Change4Life website promote fruit and vegetables as a source of fibre and encourage healthier high-fibre snacks such as nuts, seeds, fruit and vegetables (DH 2016).

It may be assumed that if initiatives to reach 5 A DAY are successful, we may see a concurrent increase in fibre intake in the UK. However, an analysis of the impact of the 5 A DAY campaign, taking into account changes in price over time, estimated that it has probably been responsible for an increase of just 0.3 portions per person per day, with differences observed according to income groups and no impact seen in the first 2 years (Capacci & Mazzocchi 2011). Similarly, a review of initiatives promoting fruit and vegetable consumption to general populations reported an increase in average consumption of a mere 0.2-0.6 portions per person per day (Pomerleau et al. 2005). In contrast, Denmark's 6 A DAY initiative, which promoted consumption of 6 portions or 600 g of fruit and vegetables per day, by increasing the accessibility of fruit and vegetables in schools, restaurants and workplaces, has been reported as more successful. Between 1995 and 2002, fruit intake rose by 64% and vegetable intake increased by 33% (National Food Institute 2005). Mean intakes of fruit and vegetables between 2003 and 2008 amongst Danish adults (18-75 years) were reported to be 442 g per person/day, higher than the WHO recommendation of 400 g (National Food Institute 2010). By contrast, mean intake of fruit and vegetables in the latest UK NDNS was reported as 348 g (Bates et al. 2014).

As well as fruit and vegetables, campaigns to increase wholegrain intake in the population may improve fibre intake. Again in Denmark, a public health campaign was initiated in 2009 to increase wholegrain consumption (Brinch-Nielsen & Neese 2013). Mean wholegrain intake increased from 32 g to 55 g/day between 2004 and 2012 (Mejborn et al.

2013). UK adult intakes of wholegrain, as discussed above, have been reported as 20 g/day (Mann et al. 2015), though in Denmark, high-fibre bread (containing >6 g of fibre per 100 g) is a traditional part of the diet which may partly explain the difference in wholegrain intakes between the two nations (Nordic Council of Ministers 2012).

In 2005, the Whole Grain Stamp was launched in the US by The Whole Grains Council to encourage consumption (The Wholegrains Council 2003). Two similar logos are available to place on eligible products, one for those which contain either at least 8 g of wholegrains per serving (but may also contain refined grains) and the 100% Whole Grain Stamp for products which contain at least 16 g of wholegrains per serving and all of its grain ingredients are wholegrain. The Whole Grain Stamp was briefly tested in the UK on bread by Morrison's supermarkets in 2008 but came under the scrutiny of FSA guidance because the Stamp, reflecting US dietary guidelines, recommends 48 g of wholegrains/day, which is not a UK recommendation. Other campaigns undertaken by The Wholegrains Council have been 'Just Ask for Whole Grains', a grassroots campaign that involved nurses, dietitians and teachers, and the 'Whole Grains Challenge', a campaign for restaurants to provide at least one wholegrain choice. For example, McDonald's introduced a bun for premium chicken sandwiches which contained 8 g of wholegrains and some Chinese restaurants added brown rice as an option. Three years after the introduction of the Stamp, market research reported that consumption of wholegrains rose by 20% overall, with 18-34 year-olds increasing their consumption the most, at 38% (The Wholegrains Council 2009). Although, according to national survey data, fibre intake amongst adults aged 20 years and over only increased from 15.5 g in 2003-2004 (USDA 2004) to 15.9 g/day in 2007-2008 (USDA 2008).

In 1989, Sweden developed the Keyhole symbol for food packaging to help consumers identify products and meals in restaurants and canteens which contain less fat, sugars and salt and more fibre than products of the same type not carrying the symbol. The Keyhole has also been widely used in Norway and Denmark since 2009 and more recently, Iceland (The Norwegian Food Safety Authority 2012). Food authorities in the Nordic countries have set criteria which foods must adhere to in order to bear the symbol (EFTA Surveillance Authority 2014). For example, flour and grain products must contain minimum amounts of wholegrain and fibre, depending on the type (e.g. bread must contain at least 30%

wholegrains and 5 g of fibre per 100 g and pasta must contain at least 50% wholegrain and 6 g of fibre per 100 g); breakfast cereals must contain at least 55% wholegrain and 6 g of fibre per 100 g and porridge must contain at least 55% wholegrain and 1 g of fibre per 100 g after preparation. Ready meals, pizzas, soups and sandwiches must contain minimum amounts of vegetables, legumes or fruit (e.g. 25 g per 100 g of sandwich and 50 g per 100 g of soup) and cereal elements within these foods must contain minimum amounts of wholegrain. Early research in Sweden indicated that women who had more knowledge of the symbol reported having a higher intake of Keyhole-labelled high-fibre foods, but this was not the case in men (Larsson et al. 1999). By the end of 2011, 98% of consumers in Norway and Sweden and 88% of those in Denmark recognised the symbol (Swedish National Food Agency 2013) and consumer research carried out in 2015 indicated that 85% knew that the symbol means a healthier food choice, 40% saw it as a tool that makes it easier to choose healthier options and 30% take the symbol into account when food shopping (Determinants of Diet and Physical Activity 2015). Recent modelling work has indicated that switching to Keyhole-labelled products would increase dietary fibre intake by 4.7 g/day (Norwegian Directorate of Health 2015).

Health professionals and fibre messaging

Modifiable lifestyle-associated risk factors, such as diet and bodyweight, are significant contributors to the development of chronic disease (WHO 2007) and, as such, consumer education on healthy lifestyle behaviours is key for both disease prevention and management. Health professionals may seem ideally placed for such a task, as they have both the opportunity to discuss lifestyle issues with patients and are a trusted source of health information. However, a number of significant barriers have been identified in relation to the delivery of dietary advice during routine health appointments. For example, research has suggested that health professionals receive little nutrition training, are ill-equipped to assess their patients' diets and nutritional status, as well as provide dietary advice (Kris-Etherton et al. 2015) and that time available with patients is limited (Ball et al. 2010). Furthermore, health professionals may lack the confidence to deliver dietary advice (Barlow et al. 2010) or feel uncomfortable discussing issues of overweight and obesity with their patients (Falconer et al. 2014; Doorley et al. 2015). This is compounded by the

problem that two-thirds of health professionals are overweight themselves, increasing their sensitivity to discuss diet-related issues (DH 2011).

A qualitative study by Cass et al. of 20 Australian female practice nurses used a thematic trend analysis to investigate the perception of nurses around their role and competency to provide nutritional care to patients with chronic disease. Practice nurses recognised that their ability to build a good rapport with patients, and the fact that they are seen by patients to be more approachable than GPs, placed them in an ideal position to deliver nutrition information. However, they also raised a lack of confidence in providing nutrition care, a lack of specific nutrition training and inadequate time. The practice nurses were also reluctant to cross professional boundaries, and a lack of clarity was noted in what constitutes basic nutrition care (to be delivered by nurses) and more specialised care (needing referral to a dietitian). Negative patient attitudes towards diet were considered disincentives to offering dietary advice (Cass et al. 2014).

Views and practices of practice nurses towards dietary fibre: Results of an online survey

In order to further explore knowledge of dietary fibre amongst practice nurses, BNF developed an online survey, which was disseminated by Sensory Dimensions Ltd, Reading. To our knowledge, there are no validated questionnaires that have been designed for this purpose. Survey questions were therefore adapted from published questionnaires investigating other aspects of nutrition knowledge of health professionals (Green et al. 2000; Warber et al. 2000; Hankey et al. 2004; de Pinho et al. 2013; Nowson et al. 2015). The survey included 30 questions, which were a mixture of multiple choice, open-ended questions and case studies on patients with the following conditions: high blood cholesterol, impaired glucose tolerance and obesity, constipation and increased risk of colorectal cancer. Although the survey was designed to examine knowledge of dietary fibre, as well as perceptions of the importance of fibre in relation to the prevention and treatment of different conditions, questions were included on a range of dietary topics to prevent awareness of the focus of investigation. A total of 50 practice nurses around the UK responded to the online survey.

The vast majority of nurses (90%) saw patients with conditions where dietary advice including fibre would be relevant (such as CVD, type 2 diabetes, obesity and

constipation). However, 1 in 6 nurses surveyed did not feel that recommending dietary changes should be part of their job and 1 in 5 reported not having adequate skills or knowledge to support their patients in dietary matters. Moreover, a quarter did not feel confident giving dietary advice to their patients.

Sixty-eight per cent of nurses reported that they frequently raise the topic of fibre in discussions around diet with their patients. Increasing intake of fibre or wholegrains was given as an unprompted healthy eating tip, although this was not reported as frequently as increasing fruit and vegetable intake. Fibre, however, was not one of the nutrition topics the nurses indicated that they are commonly asked about by their patients. These more typically related to sugars, fats, weight loss, food allergies and intolerances. This was reflected in the nurses' low rating of dietary fibre amongst the main diet-related problems for their patients (4%); those rated highest being obesity (32%), sugars (26%) and fats (20%).

The association of fibre with risk reduction in CVD (including decreasing blood cholesterol), type 2 diabetes and colorectal cancer, as well as its benefits for management of constipation, were fairly well, but not universally, understood (Fig. 4).

The survey indicated that there may be some common misunderstandings. For example, half of the nurses surveyed reported that a high-fibre diet can reduce the risk of type 1 diabetes, and around 30%

were unsure as to whether it could reduce risk of allergy. Furthermore, responses suggested that nurses held a somewhat negative view of 'starchy foods' as a food group, as has previously been shown elsewhere (Ipsos Mori 2012a), with many suggesting that lowering intake of such foods is appropriate for reducing cholesterol (86%) and reducing the risk of developing type 2 diabetes (80%).

Interestingly, nurses who had qualified earlier (1991 or before) were more likely to recommend increasing fibre as a healthy eating tip for the prevention of chronic diseases than those who had trained more recently (after 1991) (P = 0.04). Although this could be a chance finding, it may reflect the greater emphasis placed on the health benefits of dietary fibre, including the popularity of the 'F-Plan diet', in the 1980s (Eyton 1982; Eastwood & Passmore 1983). This was influenced by the work of Dennis Burkitt in the 1970s and 1980s comparing health outcomes associated with low fibre consumption in the Western diet with the high-fibre diets observed in Africa. His book, Don't Forget Fibre in your Diet: To Help Avoid Many of Our Commonest Diseases (Burkitt 1979), and his theories had a large impact on the general public, as well as the scientific community. In comparison, many popular diets in more recent times have focused on low carbohydrate and low sugars intakes, with a poor perception of starchy carbohydrates as noted in the FSA surveys.

100 -, 90 -80 -70 -60 -50 -40 -30 -20 -10 -0

■ Highly appropriate

■ Somewhat appropriate

■ Not appropriate □ Don't know

Reducing cholesterol

Reduce type 2 Reduce diabetes risk colorectal cancer risk

Figure 4 Perceived appropriateness of increasing fibre in the diet for preventing or treating various conditions reported by 50 UK practice nurses in response to questions relating to case studies.

Awareness of benefits between fibre and chronic disease risk

Three quarters of the participants regularly provided advice for patients with CVD and increasing fibre intake was considered to be highly appropriate advice for an overweight patient with high blood cholesterol by most (60%) respondents (a similar proportion to reducing sugars intake). With regard to foods for cholesterol lowering, only a quarter of the nurses would recommend oats, although this was reported more frequently than plant sterols and stanols (22%), nuts (12%), probiotic yogurts (12%) and soya-containing foods (8%).

Almost all nurses regularly provided dietary advice for patients with diabetes and obesity. When presented with a case study of an obese patient with fasting blood glucose levels indicative of impaired glucose tolerance and asked about highly appropriate dietary changes, the most commonly cited were reducing sugars and eating more vegetables (with fruit less strongly recommended). Eating more fibre was also considered

a highly or somewhat appropriate dietary change by around 90% of the participants, but 8% reported being unsure as to whether such advice was suitable.

Two-thirds of nurses considered increasing dietary fibre as highly appropriate advice for reducing risk of colorectal cancer, but they reported increasing fruit and vegetable intake, and reducing saturated fatty acid and alcohol intake more frequently.

Practical fibre knowledge - nurses' awareness of fibre-containing foods

From a list of mixed foods, most nurses were able to identify those that were high in fibre, but when unprompted, participants were likely to recognise fruit, vegetables and wholegrains for increasing fibre intakes, but less likely to suggest other fibre-containing foods such as nuts, seeds and pulses (although interestingly many nurses indicated from a list of given tips that adding pulses to stews was a dietary change they would advise to increase fibre). Just over half of nurses said they would encourage their patients to choose foods labelled 'high in fibre'.

Some of the barriers suggested by the answers from the survey to providing dietary advice included lack of time during appointments and the feeling that patients would be dissatisfied with a concentration on lifestyle modification rather than a medical prescription.

Conclusion

The review of Carbohydrates and Health, published last year by SACN (SACN 2015), emphasised the importance of dietary fibre in relation to health, concluding that there is an association between high fibre intake and lower risk of CVD, type 2 diabetes and colorectal cancer. Whilst links between fibre and markers of gastrointestinal health have been demonstrated, further experimental evidence is required to determine the exact mechanisms that may be responsible for type 2 diabetes and CVD risk reduction. Such evidence could be instrumental in informing future EFSA health claims.

Most people in the UK will need to make substantial changes to their diet in order to achieve the new recommendation for adults of 30 g of fibre/day. This will require basing meals on starchy foods (predominantly wholegrain), consuming plenty of fruit and vegetables and a variety of other high-fibre foods and snacks. Unfortunately, whilst the importance of consuming 5 A DAY is well recognised by the public, perceptions of starchy carbohydrates are often poor as a

result of negative media coverage and weight loss diets (i.e. low-carbohydrate diets) that suggest starchy foods to be 'fattening' and lead to weight gain if consumed frequently.

Evaluation of schemes, such as the Whole Grain Stamp in the US and Nordic Keyhole labelling, suggest that clearly recognisable signposting of the nutritional quality of foods (e.g. contains wholegrain, high fibre) can be effective in increasing awareness of health benefits amongst consumers. Promotion of good dietary patterns, as depicted by the recently launched Eatwell Guide, which includes plenty of fruit and vegetables, wholegrain and high-fibre starchy foods, beans, peas, lentils, nuts and seeds will increase fibre in the diet, as well as dietary quality via the displacement of calorie-dense, nutrient-poor foods. Educating the consumer is therefore important. However, knowledge is rarely enough to elicit behaviour change. Awareness of the 5 A DAY message is high but, as a nation, we are still not achieving this target. As outlined in this paper, there are a significant number of barriers for many consumers to overcome to achieve a diet containing the variety of fibre-rich foods to promote good health.

Improving the availability of fibre-rich foods that are accessible, affordable and desirable will be important. For example, offering wholegrain and high-fibre starchy foods in restaurants and cafes could help to increase consumer familiarity and enjoyment of these options. Although innovation to incorporate high-fibre ingredients into widely consumed products may also support increased intakes, it is important to determine whether addition of fibre isolates can bring the same health benefits as foods in which fibre is present as a naturally integrated component. Whilst there is evidence that particular extracted and isolated fibres have positive effects on blood lipids and colorectal function (e.g. beta-glucan), due to the smaller evidence base, it is not known whether these components confer the full range of health benefits associated with the consumption of a mix of dietary fibre-rich foods; therefore, it is not advisable that stand-alone fibre isolate products are used as a substitute for a healthy, balanced diet.

Barriers relating to food labelling have also been recognised by SACN, with one of its research recommendations in Carbohydrates and Health stating that a standardised definition of 'wholegrain' and whole-grain foods should be developed, both to facilitate recommended portion sizes for wholegrain foods and to complement public health messages about the importance of dietary fibre.

Ensuring health professionals are kept up-to-date with the scientific evidence that underlies the

importance of high-fibre diets, as well as trained in the delivery of practical healthy eating messages as part of their initial and Continued Professional Development is of utmost importance. Resources, such as the new Eatwell Guide, with its emphasis on high-fibre starchy foods, fruit and vegetables and plant-based sources of protein as the basis for healthy eating patterns, are valuable tools but it is likely that more will need to be done to support the key messages of this food model, particularly to address common misconceptions around starchy carbohydrates. Training and resources are needed to help redress the balance in an environment where there is a strong focus on the need for sugars reduction, perpetuated by the media, which is overshadowing the importance of other aspects of the diet including dietary fibre. Messages around dietary patterns, rather than single nutrients, are likely to encourage dietary changes that support greater reduction of chronic disease in the UK.

Conflict of interest

The British Nutrition Foundation is grateful to Kellogg's for financially supporting time spent on the preparation of this review and the survey of practice nurses. The views expressed are those of the authors alone.

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