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ASSOCIATE PARLIAMENTARY FOOD & HEALTH FORUM Food Myths – from aphrodisiacs to detoxification and super-foods 5-6.30pm, Tuesday 26 January 2010 Committee Room 4a, House of Lords Minutes Introduction Lord Rea welcomed members and guests to the meeting. The subject, food myths, had been suggested by our former Vice-Chairman, Ian Gibson, who thought there was too much nonsense talked about food. The aim was to dispel some of these myths. Lord Rea suggested that the special nature of the problem in Britain is that food myths are too often made to look like science. This meeting should help us to decide whether some of the old wives’ tales and companies’ claims are well founded or not. Lord Rea introduced the two guest speakers: Kevin Gould and Catherine Collins. Kevin Gould, chef, journalist and author Kevin said he would like to illustrate some examples of food myths that may have some truth in them as well as myths with no foundation in fact. During her last pregnancy, his wife had been warned not to eat organic cheese. This is a piece of misinformation that remains current today in the NHS, but it is the age of cheese rather than whether it is organic or non-organic that indicates whether it may contain listeria. Consumers tend to think that all “e numbers” are bad, but some exist for “good” ingredients such as curcumin, which is the ingredient in turmeric, which many Indians and others believe helps prevent cancer. The problem is that labels make us dummer. If you try to read food labels you will find they might as well be written in latin. Of course the biggest myth concerns fat. Last week a professor suggested that butter kills you and should be banned. At the same time, there is a great deal of confusion that is designed to ensure that misinformation persists, so that it can be perpetuated in the media and will support the sale of products. Polyunsaturated fats are portrayed as good, but some contain hydrogenated fats (trans fats) and they are bad for you. Kevin said that as a 50 year old man, he is promised that if he eats a certain amount of almonds a day, it will lower his cholesterol. Aphrodisiacs form the basis of several long standing myths. Rocket was banned in medieval monasteries because it was thought to “inflame the blood”. Oysters have long been thought of as an aphrodisiac, possibly because of their association with Aphrodite, the Goddess of Love; possibly because they are very expensive and if you can afford to buy them that makes you attractive to some people; not, it seems, because they are a good source of zinc. The Karma Sutra suggests that if you eat chickpeas every day, you will be able to enjoy 100 women. Rhino horn does not work either! Sheep’s testicles are another famous aphrodisiac, but they are not good for your cholesterol levels. Chairman: Lord Rea Vice-Chairmen: Baroness Miller of Chilthorne Domer, David Drew MP & The Countess of Mar Secretary: The Earl Baldwin of Bewdley Treasurer: Baroness Gibson of Market Rasen Associate Parliamentary Food & Health Forum Church House, Great Smith Street London, SW1P 3AZ Tel: 020 7222 1265 Fax: 020 7222 1250 Brown sugar is supposed to be better for you than white sugar, but sometimes it is only brown because a food colour has been added to it. Kevin said his biggest bone of contention at the moment is fruit sugars. The Food Standards Agency (FSA) says that freshly squeezed fruit juice is bad for you because it will “rot you teeth”. At the same time, Innocent Drinks will tell you that a 250ml glass of one of their smoothies counts as 2 of your 5-a-Day because they are high in fibre as well as fruit juice. The majority of fairtrade products sold in the UK are further manufactured in Europe so, for example, coco beans are sent to Europe to be processed. As a result, a large part of the profit is taken by producers and retailers in Europe rather than by the producers of the beans. Fairtrade is a myth that needs to be debunked. Information is not power because there are so many public campaigns about food that become converted into something else, so messages emerge that are uncertain or incorrect. Kevin’s fear is that food has become an area that makes people fearful rather than being something that should be enjoyed. Questions Shirlee Posner of the Design and Technology Association expressed interested in Kevin’s comments about Innocent Drinks and asked him what it was about the fruit juices he was involved in working on that made them different. Kevin said the “secret” is that you need to take the whole fruit and puree it and put that in the bottle. The products he is involved in, sold under retailers’ own labels, do not go off straight away, but last 3-4 days because the fruit is washed very carefully before it is pureed. It is also important to use fruit when it is ripe. A typical smoothie will include aseptic puree, pureed in the country of origin, then sterilised to kill any bugs. Other companies use frozen or pasteurised purees. Even if they use low temperature pasteurisation, it will have an effect on temperature sensitive vitamins such as vitamin C. Helen Conn of the Food Additives and Ingredients Association made the point that Innocent Drinks are made to last for up to 3 weeks and therefore need to be more stable than a product made to last a number of days only. Kevin accepted that, but said he was trying to debunk the myth that Innocent Drinks’ smoothies are “fresh” fruit juice. He said the bonus in terms of shelf life is for the producer and retailer because once their smoothies are open they will not last longer than other fruit juices in the fridge. Lord Rea asked Kevin if he really thought people were frightened of food. Kevin said he does think that many people are fearful about certain foods. Public health practitioners have a duty to inform the public and they will report new research that indicates certain foods may be dangerous, but all too often the context surrounding such messages indicating that it may not be relevant for many people only goes in the small print. Kevin was asked if he agreed that the FSA was targeting the wrong target when promoting 1% fat milk rather than skimmed milk and whether it should focus instead on higher fat food products. He said people in other countries are not told what sort of milk they should drink and the consumer can become bewildered by such information. Lord Rea asked Kevin who he thought is mainly responsible for food scare-mongering. Kevin said that manufacturers sometimes welcome scare stories because they can provide a product in response. He suggested that the FSA’s messages need to be louder and clearer and that sometimes more reflection is needed before a new message is communicated. Ailbhe Fallon of Fallon Currie Consulting said she had been working on a project for the last couple of years looking at additives and she would echo Kevin’s comment that the UK is the most food phobic country in Europe. We like talking about things that are bad for us. She has also tracked a lot of food scare stories that have appeared in the media and most of them come from research scientists or the FSA, rather than food manufacturers. The lack of clarity of the FSA’s messages needs to be addressed. Kevin agreed and suggested that the traffic light food labelling scheme is a good example. Under the scheme freshly squeezed orange juice gets a red label because of its sugar content despite the fact that it is a good source of vitamin C. Thai cooking 2 sauce gets a red label because of its salt content, but this disregards portion size and the fact that you would only need half a teaspoonful to feed 8 people. He suggested this was more the result of muddle than a cynical manoeuvre, but it works against a healthy food culture in the UK. Cathy Court of Netmums said they work with the FSA and they support the FSA’s saturated fat campaign, which encourages people to take small, practical steps to improve their diet, such as switching to lower fat milk or cutting the visible fat off meat. Kevin said that only 15% of fat eaten by a household is consumed in this way and most is consumed in foods such as cakes and biscuits. Cathy agreed, but said the FSA is also encouraging people to eat more healthily by trying to persuade more people to cook their own food. She also said that busy parents like the traffic light labelling scheme because it enables them to make quick and easy choices. She agreed it may need to be revised for certain foods, such as cheese and marmite, but said it does help consumers to choose between different versions of the same food, such as ready-made lasagnes. Lord Rea agreed that the messages need to be clearer so that consumers are aware they can eat foods with red labels, such as cheese. Kevin suggested the FSA should campaign to take the fear out of cooking for people. It should be positive about the joys of cooking. The only area where it seems to be having any success is among ethnic communities, where many people do still cook at home. Lord Rea said there were also encouraging signs in schools, for example the School Food Trust’s Let’s Get Cooking project. Kate Christ of the School Food Trust (SFT) said the Let’s Get Cooking project is using Lottery funding to set up an initial network of 5000 school cookery clubs by 2012, which will enable over one million children and family members to learn new cooking skills. Kevin agreed the scheme was excellent and said the great sin had been removing cooking from the school curriculum. Yvonne Gritschneder of the National Heart Forum said the traffic light scheme had been developed with a view to encouraging food manufacturers to reformulate their products and the FSA is working with the food industry to encourage manufacturers to reformulate their products so they contain less salt. Kevin accepted this point, but said that 90% of food sold in the UK is sold through 6 multiples, so those companies have more power than the FSA and food manufacturers respond to what they want. Traffic light labelling can help consumers but it needs to go on composite foods not single ingredients. Sara Jayne Stanes of the Academy of Culinary Arts said she has been involved in a small charity, Chefs Adopt a School, which is not lottery funded, but manages to work with thousands of children a year. She said it is very important that children are taught about the source of their food as well as how to cook and not everyone is aware of the 5-a-Day message so it needs to be promoted further. Sara suggested that fairtrade has helped coffee producers in Mexico by encouraging them to form supplier co-operatives, which has strengthened their negotiating power. Kevin said that he has had a 20 year row with the Fairtrade Association for not controlling the marketing of fairtrade products. He also criticised the accreditation process which he said was very bureaucratic and time consuming. Catherine Collins, lecturer and Chief Dietitian, St George’s Hospital, London Catherine said that listening to the debate reminded her that a dietitian could say something about any food issue and that an important part of a dietitian’s role is to educate the general public about food. Super-foods are so called because they contain certain ingredients. Traditionally we have classified foods according to certain themes, so for example we would look at things like their protein or fat content. Sometimes we look at group foods by their ability to prevent certain diseases, for example looking for iron-rich foods such as meat and breakfast cereal products to prevent anaemia, or vitamin D rich foods to prevent ricketts. Some foods have a nutritional role that is not essential to life, but which can augment health, for example prebiotic fibres to support gut bacteria or plant phytochemicals, such as anti-oxidants. 3 The idea of super-foods is not a new concept. Derek Jelliffe (see slide 4) published a paper over forty years ago that classified super-foods into five groups: “cultural super-foods”, which enable a population to get by, perhaps because they are a good source of calories; “prestige foods”, which people move on to once they have sufficient cultural super foods; “body image foods” which often have a religious or philosophical aspect, such as ying and yang foods; “sympathetic magic foods” such as pomegranates, and “physiological food groups” such as those we think of as constituting a healthy diet. The last two groups are as relevant now as they were 40 years ago. Another research scientist, Dr Ancel Keys, a physiologist at the University of Minnesota and the Director of the Director of the Seven Countries Collaborative Study, was surprised when he saw that so many men in America were dying prematurely. He was one of the first authors to support the Mediterranean Diet, the dietary principles of which have been ratified in over 450 clinical papers of subsequent research. In 2008 the BMJ published a systematic review of the Mediterranean Diet, which included 12 studies involving over 1.5 million subjects followed for 3-18 years, which were divided into 8 cohorts. It found a 9% reduction in overall mortality; a 9% reduction in death from cardiovascular disease; a 6% reduction in risk of cancer, or dying from cancer; and a 13% reduction in risk of Parkinson’s disease and Alzheimer’s disease - probably because the diet supports vascular health. Catherine showed a slide (slide 6) that shows for each of two sets of clinical trials, there was a clear trend of reduction in risk associated with following a Mediterranean Diet. The “diamond” on each graph, represents a summary of the results of both sets of trials and clearly shows that the Mediterranean Diet is protective against the risk of developing or dying from cancer and the risk of dying from heart disease. Fortunately we do not need to have started eating the Mediterranean Diet at a very young age for it to be beneficial. Slide 7 shows the results for people who were recruited to a Mediterranean Diet in middle age after being diagnosed as being at risk of coronary heart disease (CHD). It shows that the patients who adopted the Mediterranean Diet, took exercise and stopped smoking, reduced their risk of dying prematurely by 40% - so it is never too late to adopt a health diet! Catherine expressed disappointment that the FSA’s “eatwell plate” and subsidiary messages are confusing. She suggested that the FSA needs to create layers of messages that are better coordinated with the “eatwell plate”. In conventional research we use population studies to try to identify trends and then seek to apply these lessons to the general public. By contrast evidence to support super-foods is normally done in a test tube looking at biological processes. It focuses on cell and animal research rather than looking at human beings as a whole. People are affected by their diet, but also their lifestyle and environment. Dietary factors can only affect part of the factors affecting human health and it is difficult to separate out the other factors. However, super-foods trials often ignore other factors affecting human health. It is a reductive process. James Lind discovered the link between eating limes and reducing the risk of scurvy. Takaki Kanehiro identified poor diet as a cause of beri-beri in 1884, against the prevailing opinion that beri-beri was an infectious disease. In the early days science had very good results in identifying foods that are good for us. But recent research has focussed on a negative reductionist approach. The recent Cochrane Review of anti-oxidant research trials (see slide 11) found that eating antioxidant supplements was not beneficial in terms of reducing the risk of cancer. Indeed it found a significant increased risk of bladder cancer in a subgroup of four trials. Journalists have a lot to answer for in terms of promoting super-foods, although the new EU regulation on nutrition and health claims means that they cannot now describe foods as Super Foods. 4 Super-foods are defined in the Oxford English Dictionary as “a food considered especially nutritious or otherwise beneficial to health and well-being”. The Times list of the “top 100 foods to boost productivity” cites certain foods as being protective against cancer and long term illness, but not one of these foods (see slide 12) is rich in protein, which is essential for the immune system. Ben Goldacre has a rather cruel way of looking at Daily Mail reports on foods, to see whether the foods are portrayed as “killer foods” or “supers-foods”. Slide 13 shows The Daily Mail’s list of super-foods in 2007, although tofu is uniquely distinguished in that it appears on both lists. A super-food is a food with good PR marketing behind it. We can look at the ingredients of superfoods that have benefits, such as anti-oxidants, but they do not tell the whole story. Our bodies produce free radicals as long as we are breathing. A small amount is beneficial because they test cells, but too much can damage cells. A lot of ingredients in super-foods do help by mopping up free radicals, but what we are not told is that they often replace them with weaker free radicals that also need to be dealt with. The issue of detoxification crops up frequently. The body is detoxifying all the time. All our organs have the capacity to detoxify, but it is usually associated with the liver and the spleen. There are two types of detoxification. Phase one enzymes (activators) process food altering the chemical your body needs to remove, by adding single nitrogen or oxygen molecules. However some toxins are fat soluble and because the body is water soluble some toxins remain after phase one. Phase two enzymes (excretors) deal with these fat soluble toxins, often by making them water soluble. It can be induced by particular ingredients found in foods, such as anthrocyanins found in cabbage and broccoli, which contain cyanide. The idea that all super-foods are benign is a myth. Quite a lot of them contain small doses of toxins that help keep us healthy by stimulating the body to respond to them. There are various substances that can interfere with the normal functioning of a cell. For example, if a person consumes a substance that is carcinogenic it may in due course lead to the formation of a tumour. Many super-foods are linked to cancer blocking or cancer suppressing agents (see slide 17). Artichoke extract is often promoted as stimulating liver detoxification, but if you eat a range of fruit and vegetables, it is superfluous. Polyphenols can be divided into five sub-groups (see slide 18) each of which can be broken down into other groups. But this complex issue is often represented in a simplistic way in the media. It is interesting to look at how a beneficial ingredient in a food can be absorbed into the body and its impact, for example curcumin in turmeric. Curcumin has a definite benefit in that it has antiinflammatory, antioxidant, and anti-tumour properties. The problem is that the level of curcumin you need to gain that benefit is not easily absorbed from food in a normal diet (see slide 20): you would need to eat 200g of curry powder a day. Many media reports exaggerate the benefit of beneficial ingredients in this way because the levels required to gain the clinical benefit are not practical. If you accept that you need to look at the bioavailability of positive ingredients in super-foods, you also need to take account of the impact of cooking. In some cases cooking increases the bioavailability of good ingredients, for example the lycopene in tomatoes and the carotene in carrots. However, some positive ingredients are lost if, for example, vegetables are boiled for a long time. Microwaving and steaming food rather than boiling it, helps to retain its nutritional content. Several companies promote pomegranate juice. One claim, now no longer allowed, was that pomegranate juice contains ten times as much tannin as tea. But the active ingredient, ellagitannins, has a half life of only 2-3 hours. The half life of ellagitannins in tea is similar (2-4 hours) but because British people drink tea every 2-4 hours the benefit is continuous and it is cheaper. 5 The bioavailability of ingredients in food, cooking food and its interaction with other foods all affect the benefit of eating certain foods. We need to focus on diet and health and should look at whole foods, that is, the “plate model”. The Mediterranean Diet is better than the sum of the individual foods it consists of because of the synergy of these different foods (see slide 25). Slide 26 shows the way in which the body metabolises foods. Every food hits part of these metabolic pathways and promoting super-foods is too simplistic an approach for something that is so complex. Questions Baroness Masham asked if bought orange juice is as bad as Kevin Gould suggests. Catherine said that sometimes processing increases the bioavailability of ingredients. Freezing can protect nutrients – as in the case of frozen peas unless peas are picked fresh and eaten within two hours. However, heat processing does affect nutrient content. If a product is sterilised there will be a reduction in nutrients, but not enough to make having a glass of orange juice worthless. Freshly chilled or UHT juices will have less vitamin C than fresh juice, but it still makes a significant contribution to a diet and it is often cheaper. Lord Rea raised the issue of orange juice receiving a red label under the traffic light labelling scheme because of its sugar content. Catherine said that Innocent Drinks have successfully lobbied the FSA to classify their smoothies as 2 portions of 5-a-Day because of their fibre and fruit juice content. Whereas the fruit juices of other manufacturers who combine two fruits in their juices only count as one portion. The fact that we are eating a lot more ready-processed foods means that we are eating a lot more fructose and without glucose it can be poorly digested. Catherine said that milk sugars are counted differently towards total daily sugar content. Fruit juice sugars, sugars from fruit, and sugars added to foods and drink all count towards the recommended maximum intake for sugar in the UK (called the RNI value in the UK, set at no more than 10% of total calories to come from sugar). Milk sugar is excluded from this total, as it is considered less cariogenic and it is also present as an intrinsic component of a nutritionally beneficial foodstuff. However, companies using the %GDA nutrition labelling scheme to promote nutritional awareness usually include all sugars in their total without separating out the milk sugar from non-milk sources. Baroness Masham asked Catherine to comment on fruit juices for diabetics. Catherine said that some juices have a lower sugar content, for example water melon, so they could be better for diabetics. Fructose does not show up in the blood glucose monitoring done by diabetics, so in the past certain fructose-high juices were promoted to diabetics, but this is no longer happens because high fructose diets are now associated with increasing risk of metabolic syndrome and central obesity. Eating 5 portions of fruit of course takes longer than drinking a couple of smoothies and results in slow absorption of sugars. Lord Rea asked if he would be correct in assuming that a healthy body is good at detoxifying toxins and super-foods do not necessarily add anything beneficial. Catherine said super-foods can have beneficial ingredients, but if you eat a balanced diet it is probably not necessary to single out individual ingredients. She suggested that one of the problems we have is the “tyranny” of food choices and knowing when to stop eating. We now have instant access to food, so the detoxifying concept is a myth in metabolic terms, but it may give us a rest from food choices. Baroness Masham asked Catherine to comment on the interaction of certain foods and drugs, such as grapefruits and statins. Catherine said the problem there is that some food constituents were metabolised along the same Phase I enzyme pathways as prescription drugs, for example naringenin found in grapefruit and pomelo, and statins, and some anti-rejection drugs used post transplant. Metabolism of the food substance can lead to an increase in drug level which may have toxic effects, for example the potential for muscle damage with high levels of statin in the bloodstream. For this reason some drugs list foods to be avoided for the duration of their use. 6 Lord Rea said that Ben Goldacre has suggested that all our bodies need is plenty of water and they will detoxify naturally. Catherine said that water does help with phase one detoxification because it contains oxygen and hydrogen and because it is the medium through which toxins are eliminated. Tea and coffee are even better because they contain anti-oxidants. Cathy Court of Netmums asked Catherine to comment on acaci and gojii berries which are often mentioned as super-foods. Catherine said acaci berries are high in anthrocyanins (the ingredient responsible for the natural blue and red colour in food), but blackcurrants contain the same ingredient and are usually cheaper. Catherine suggested that such media reports reflect people’s interest in food and their lack of trust in what they are currently eating. In the old days, we did believe the simple messages we were given such as, carrots help you see in the dark and fish is good for the brain. Now we– especially journalists – have food fetishes and we like to focus on whether food is organic or non-organic, food miles, etc. The provenance of our food does not necessarily affect its quality but we like to think that it does and this feeds another food myth. Cathy Court of Netmums asked if the EU regulation on nutrition and health claims would stop journalists making claims about super-foods. Catherine said that technically the term has been outlawed but it still crops up. The Advertising Standards Authority does a sterling job of stopping wild claims, but unfortunately they deal with claims retrospectively when the damage has often already been done. The FSA provides guidance on a healthy diet, but we need messages that are tailor made for different age groups, which is where the GDA food labelling system was helpful. Growing children need a different diet to that required by health conscious middle aged women. The traffic light labelling scheme is very good at point of sale, but it is not good at distinguishing between, for example, cheeses. If we taught people about food and used the “plate model” it would help consumers put food messages in context. Conclusion Lord Rea thanked Catherine for the very interesting lesson in metabolic physiology and said that the key conclusion appeared to be that a whole foods/balanced diet approach is better than being mesmerised by so called super-foods. Lord Rea announced that our next meeting will be held on Tuesday 23 February, when we will be discussing school breakfast clubs. Our guest speakers will be: Dr Michael Nelson of the School Food Trust, Jackie Crombie of Greggs and Jenny Walton of Kellogg’s. CLC, January 2010 7