BNF LOOKS AT THE RECOMMENDATIONS IN THE WORLD CANCER RESEARCH FUND 2018 THIRD EXPERT REPORT* AND HOW IT COMPARES TO UK GUIDELINES

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1 BNF LOOKS AT THE RECOMMENDATIONS IN THE WORLD CANCER RESEARCH FUND 2018 THIRD EXPERT REPORT* AND HOW IT COMPARES TO UK GUIDELINES *WCRF/AICR Diet, Nutrition, Physical Activity and Cancer: Third Expert Report from the World Cancer Research Fund

2 BNF looks at the WCRF 2018 Third Expert Report from the World Cancer Research Fund and how it compares to UK guidelines WCRF/AICR Diet, Nutrition, Physical Activity and Cancer: Third Expert Report from the World Cancer Research Fund BE A HEALTHY WEIGHT Be a healthy weight Be a healthy weight Ensure that body weight during childhood and adolescence projects towards the lower end of the healthy adult BMI range Keep your weight as low as you can within the healthy weight range Avoid weight gain (measured as change in body weight or waist circumference) throughout adulthood Reducing obesity, particularly among children, is one of the priorities of Public Health England (PHE). The particular importance of childhood obesity has been recognised by PHE within the childhood obesity plan. PHE aims to increase the proportion of children leaving primary school with a healthy weight, as well as encourage reductions in levels of excess weight in adults. The importance of waist measurements with regards associations of abdominal obesity and health risks are acknowledged in the NICE guidelines. For men, the chance of developing health problems is higher if waist measurement is more than 94 cm (37 inches), and higher still if it is more than 102 cm (40 inches). For women, the chance of developing health problems is higher if waist measurement is more than 80 cm (31.5 inches), and higher still if it is more than 88 cm (34.5 inches). Evidence on the association between body weight/fatness and increased risk of several cancers has strengthened, including mouth, pharynx and larynx, oesophageal, stomach, pancreatic, gallbladder, liver, colorectal, breast (post-menopausal), ovarian, endometrial, prostate and kidney cancer. The goals refers to the importance of weight tracking i.e. obese children and young people are more likely to grow up to become obese adults. Adults and children however use different BMI obesity references. The prevalence of obesity in children has been measured using BMI (using the 85th centile for overweight and 95th for obese), whereas in adults the following BMI classification is used: 18.5 to 24.9: healthy weight 25.0 to 29.9: overweight 30.0 to 39.9: obese 40.0 or above : severely obese It is also important to emphasise that weight should be within the healthy weight range there are increased clinical risks of being underweight and at risk for malnutrition (below a BMI of 18.5), which can be a fairly prevalent problem in older adults in UK and Europe.

3 BE PHYSICALLY ACTIVE Move More Be physically active Be at least moderately physically active and follow or exceed national guidelines Limit sedentary habits UK on physical activity are based on guidance from the Chief Medical Office (CMO) on how much physical activity people should be doing, and reflect World Health Organisation. For example To stay healthy, adults aged 19 to 64 should try to be active daily and should do: Or: at least 150 minutes of moderate aerobic activity such as cycling or brisk walking every week and strength exercises on 2 or more days a week that work all the major muscles 75 minutes of vigorous aerobic activity such as running There is strong evidence that physical activity protects against several cancers including colon, breast (postmenopausal) and endometrial cancer. Regular physical activity helps to keep body weight at a healthy level, and being overweight or obese can increase the risk of cancer. However, the activity itself also has a protective effect, which is independent of its effects on bodyweight. Sedentary behaviour is not simply a lack of physical activity but a cluster of individual behaviours where sitting or lying is the dominant mode of posture and energy expenditure is very low. Scientific research has shown associations between both low levels of physical activity and/or increased sedentary behaviour with poorer health outcomes. The word at least reflects WCRF emphasis that this represents the minimal amount that should be undertaken. In addition all adults should minimise the amount of time spent being sedentary (sitting) for extended periods.

4 EAT A DIET RICH IN WHOLEGRAINS, VEGETABLES, FRUIT AND BEANS Eat more grains, veg, fruit and beans Eat a diet rich in wholegrains, vegetables, fruit and beans Make wholegrains, vegetables, fruit and pulses such as beans and lentils a major part of your usual daily diet Consume a diet that contains at least 30 g of fibre from food sources Include in most meals foods containing wholegrains, nonstarchy vegetables fruit and pulses Eat a diet high in all types of plant foods including at least 5 portions (400g) of a variety of non - starchy vegetables and fruit every day In 2016, a revised healthy eating model the Eatwell guide changed the name of the protein group to Beans, pulses, fish, eggs, meat and other proteins to highlight the importance of plant based proteins like beans to a sustainable, healthy diet. Further to the SACN report on carbohydrates and health, published in July 2015, the UK government advised that the recommendation for dietary fibre intake should increase to 30g a day, as part of a healthy, balanced diet. The long standing recommendation for at least 5 A Day (5 x 80g) reflects the 400g recommendation. The WCRF recommendation emphasises the importance of fibre in the diet and supports the SACN recommendation for 30g fibre a day. Plant based diets (these are where a high proportion of plant foods such as fruit, veg, wholegrains and pulses are consumed but animal products may still be included) are considered healthy. However the National Dietary and Nutrition Survey suggests average consumption of these plant based foods remains low. Average current fibre intake in adults is 18.4g per day, with less than a third meeting the 5 A Day recommendation. Also, UK adults on average do not consume many pulses. A recent report suggested we currently consume around 14g pulses a day. If you eat starchy roots or tubers as staple foods eat non - starchy vegetables, fruit and pulses regularly too if possible The Eatwell guide classifies starchy staples or starchy vegetables like potatoes, yams, cassava and plantains within the starchy carbohydrate group and these are not included in the fruit and veg food group. Thus plenty of nonstarchy fruit and veg are recommended, as well as pulses as part of a balanced diet alongside starchy vegetables.

5 LIMIT CONSUMPTION OF RED AND PROCESSED MEAT Limit consumption of red meat (such as beef, pork and lamb). Avoid processed meat. Limit consumption of red and processed meat Eat no more than moderate amounts of red meat, such as beef, pork and lamb. Eat little, if any, processed meat If you eat red meat, limit consumption to no more than about three portions per week. Three portions is equivalent to about 350 to 500 grams (about 12 to 18 ounces) cooked weight of red meat. Consume very little, if any processed meat. UK message around meat consumption is consistent with the moderate meat message of WCRF and recognises that eating red and processed meat in higher quantities increases risk of colorectal cancer. However the 2011 SACN report Iron and Health couldn t identify quantitatively the amount of red and processed meat that may increase the risk of bowel cancer because of inconsistencies in the data. were therefore based on what was considered as a safe average UK intake. Therefore the Department of Health recommends are that if you currently eat more than 90g (cooked weight) of red and processed meat a day, that you cut down to 70g. A range g for total weekly red meat intake has been introduced, with a goal set that advises the population to limit intake to no more than about 3 portions a week, although the maximum total amount has remained the same. 500g cooked meat has been calculated approximately to be equivalent to g raw. Advice on processed meat is to eat little if any as the report finds the evidence on processed meat stronger than for red meat. The WCRF report recognises that red meat is a good source of iron, protein and micronutrients. In the NDNS, average adult intake is reported by combining red and processed meat together. On average, adults consume 62g day (men 77g/d, women 47g/d) equating to 434g per week (men 539g and women 329g). Red and processed meat intake in the UK, comparing the Year 1-2 survey (2008/ /10) to the most recent Years 7-8 (2014/ /16) has significantly decreased. The report states that consuming red meat and processed meat are causes of colorectal cancer which could imply an increased risk even at very low intakes. This is not clearly suggested by evidence. The evidence suggests a dose response relationship.

6 LIMIT CONSUMPTION OF FAT FOODS AND OTHER PROCESSED FOODS HIGH IN FAT, STARCHES OR SUGARS 2018 WCRF Goals Relevant UK Government/health Avoid high calorie foods and drinks Limit consumption of fast foods and other processed foods high in fat, starches or sugars Limiting these foods to help control calorie intake and maintain a healthy weight Limit consumption of processed foods high in fat, starches or sugars, including fast foods, many pre-prepared dishes, snacks, bakery foods and desserts, and confectionery The Eatwell guide recommends that foods high in fat, salt and sugar are chosen less often and in small amounts. These foods include chocolate, cakes, biscuits, sugary soft drinks, butter, ghee and ice cream. In terms of starchy carbohydrates the advice is to eat wholegrain or higher fibre versions where possible and to choose carbohydrates with less added fat, salt and sugar. However, the Eatwell guide recognises the important nutritional contribution of this food group, and SACN did not find sufficient evidence for a link between intake of starch-rich foods and any adverse health outcome. PHE has estimated there are over 50,000 fast food and takeaway outlets, fast food delivery services, and fish and chip shops in England (2014). More than one quarter of adults and one fifth of children eat food from out-of-home food outlets at least once a week. These meals tend to be associated with higher energy intake; higher levels of fat, saturated fats, sugar, and salt, and lower levels of micronutrients. Fast foods are defined in the report as readily available convenience foods that are often consumed frequently and in large portions. The WCRF report recognises that foods like burgers fried chicken, chips and high-calorie sugary drinks are energy dense and can contribute to excess calorie intake when consumed frequently and in large portions. The key though lies in the nutrients (e.g. saturated fat, salt, sugars) these foods contain rather than their degree of processing. It is also apparent that consuming foods high in saturated fats, sugars and salt will displace better quality choices such as wholegrains, fruit and vegetables and legumes from the diet. There is an increasing awareness that healthy dietary patterns are characterised typically by being rich in vegetables, fruits, wholegrains, seafood, legumes, and nuts and lower in red and processed meat; and low in sugars-sweetened foods and beverages and refined grains. The increasing consumption of out-of-home meals that are often cheap and readily available has been identified as an important factor contributing to rising levels of obesity.

7 LIMIT CONSUMPTION OF SUGARS SWEETENED BEVERAGES New Recommendation Limit consumption of sugars-sweetened beverages Drink mostly water and unsweetened drinks Do not consume sugars-sweetened drinks The advises 6-8 glasses of fluid, recommending sugar -free drinks including water and low-fat milk. Sugars-sweetened drinks have been defined as liquids that are sweetened by the addition of free sugars which will include sugars-sweetened carbonated beverages and sweetened or syrup-added coffees and tea. In the 2015 SACN report, it was recommended that the consumption of sugars-sweetened beverages should be minimised in children and adults. This was based on some evidence from trials in children and adolescents that showed sugars-sweetened beverages are linked to weight gain and intake of sugarssweetened beverages may be associated with an increased risk of type 2 diabetes mellitus.

8 LIMIT ALCOHOL CONSUMPTION For cancer prevention don t drink alcohol Limit alcohol consumption For cancer prevention its best not to drink alcohol For cancer prevention its best not to drink alcohol. If you do drink alcohol do not exceed your national guidelines. The UK Chief Medical Officers (CMOs) guideline for both men and women is: To keep health risks from alcohol to a low level it is safest not to drink more than 14 units a week on a regular basis. If you regularly drink as much as 14 units per week, it is best to spread your drinking evenly over 3 or more days. If you have one or two heavy drinking episodes a week, you increase your risks of death from long term illness and from accidents and injuries. The risk of developing a range of health problems (including cancers of the mouth, throat and breast) increases the more you drink on a regular basis. If you wish to cut down the amount you drink, a good way to help achieve this is to have several drinkfree days each week. WCRF suggests there is no level of consumption below which there is no increase in the risk of at least some cancers. This supports the 2016 guidelines developed by a group of experts, at the request of the four UK CMOs, to inform the public about known health risks from drinking alcohol, and to provide the most up to date scientific information. Like WCRF, the expert group was also clear that there are a number of serious diseases, including certain cancers, which can occur even when drinking within the weekly guideline. Whilst the risks were judged to be low at this level of intake, this means there is no level of regular drinking that can be considered as completely safe in relation to some cancers. People can reduce these risks by drinking less than the guidelines or by not drinking at all.

9 DO NOT USE SUPPLEMENTS FOR CANCER PREVENTION Don t rely on supplements Do not use supplements for cancer prevention. Aim to meet nutritional needs through diet alone. High dose dietary supplements are not recommended for cancer prevention Aim to meet nutritional needs through diet alone The Department of Health recommends certain supplements for some groups of people who are at risk of deficiency but there is no recommendation for any supplements with relation to cancer prevention. Groups where supplementation is recommended include: Folate in preconception and first 12 weeks pregnancy Vitamin D supplements in children under 5 years and at high risk groups. Advice for other adults and children over 5 years old (including pregnant and breastfeeding women) is to consider taking a daily supplement containing 10mcg of vitamin D during the autumn and winter. Vitamin B12 in vegans Most people don't need to take vitamin supplements and are able to get all the vitamins and minerals they need by eating a healthy, balanced diet, perhaps with the exception of vitamin D. With regards cancer prevention, high vitamin and mineral supplementation do not demonstrate benefit and can be harmful (e.g. high beta-carotene supplement may increase risk of lung cancer in smokers). For people who do choose to take supplements these should be bought through reputable suppliers and taken as directed. There has been some popular reporting of benefit from supplements that contain compounds such as resveratrol and curcumin (found in turmeric) but there is no scientific evidence that taking such supplements can prevent cancers in humans.

10 FOR MOTHERS BREASTFEED YOUR BABY IF YOU CAN Breastfeed your baby For mothers breastfeed your baby if you can Breastfeeding is good for both mother and baby The recommendation aligns with the advice of the World Health Organisation (WHO) which recommends infants are exclusively breast fed for 6 months NHS Choices stresses the benefits of breastfeeding for babies and mothers. The information provided on benefits includes that breastfeeding lowers risk of breast and ovarian cancer as well as osteoporosis, cardiovascular disease and obesity. Existing advice is to breastfeed exclusively for around the first 6 months, after which complementary foods should be introduced alongside continued breastfeeding. This was upheld by the 2017 SACN draft report on Feeding in the First Year of Life. OTHER NOTES OF INTEREST Salt Previous recommendation to eat less salt has been moved into a regional and special circumstances section. This recognises that foods preserved by salting may be eaten more by people that do not have access to refrigeration and that much of the strong evidence on stomach cancer and intake of foods preserved by salting (e.g. salt preserved fish and vegetables) comes from Asia. Dairy The evidence on dairy products and cancer is mixed; there is strong evidence that consumption of dairy foods help to protect against colorectal cancer. However there is also some limited evidence that dairy products might increase risk of prostate cancer. WCRF therefore do not make any specifically on dairy and cancer, although it is interesting to note that a positive association between dairy and breast cancer has not been established as this is something that is popularly reported. Cancer Survivors There is increased recognition of the potential importance of diet in cancer survivors but the evidence in this area is limited. What has been highlighted by WCRF is that cancer survivors should receive guidance on diet and physical activity from trained health professionals that can take individual circumstances into account.