By David A. Bender
The food pyramid shows fruits and vegetables as the second most important group of foods in terms of the amount to be eaten each day: 3-5 servings of vegetables and 2-4 servings of fruit. This, and the associated public health message to consume at least 5 servings of fruit and vegetables a day, is based on many years of nutritional research. Fruits and vegetables are rich in vitamins and minerals, as well as many other potentially protective compounds, and low in fat (and especially saturated fat). There is excellent evidence from a great many epidemiological studies that people who consume 5 servings of fruit and vegetables a day are less likely to suffer from atherosclerosis, heart disease, high blood pressure, and many cancers.
Things have changed in my local supermarket now, but until a year or so ago, the “five a day” message appeared above the aisles containing exotic (and expensive) fruits such as mangoes and papaya, but not those containing apples and pears, carrots and parsnips. Now, however, I find a more disturbing difference. If I buy a packet of tomatoes, there is nutritional information on the package, telling me what nutrients are present, and what percentage of my daily requirement a serving contains. Some packages also tell me how much of the produce will provide one of my five servings a day. By contrast, if I buy loose tomatoes there is no nutritional information available. Similarly, when I bought a pineapple last week there was a label around the neck of the fruit, not only telling me it was a pineapple (which I knew), but where it was grown and what nutrients it contained. The next shelf contained mangoes. These had only a small bar code label that would be decoded into a price at the checkout. Three onions in a string bag were labelled with nutrition information; loose onions were not.
All this suggests that I might be misled into believing that while packaged fruits and vegetables are a source of nutrients, loose produce that I select myself from the trays is free from nutrients. Of course, this is not so, but there is anecdotal evidence to suggest that many consumers do indeed believe that unpackaged fresh produce (and indeed unpackaged meat and fish from the counter) are not nutritious, since there is no associated labelling.
It is difficult to know what to do about this. It is not likely that shoppers would read a list of nutrition information on a poster above the loose produce – indeed, it would be very annoying if people were standing reading the posters above the produce that I wanted to select. It is annoying enough when someone blocks my access to the shelves by phoning home to ask whether we should have this or that for dinner tonight. One answer might be to expand the labels on loose fruits and vegetables to include a QR code that can be read into a smart phone. I notice that my pineapple label contains a QR code that will download recipes to use pineapple to my smart phone. Perhaps QR codes could be printed on the supermarket receipt – but that is long enough already, listing every item, how much I have saved by buying special offers and “twofers”, how many loyalty points I have earned to date, how many points I have donated to charity by using my own bags, etc.
Another trend is the marketing of some fruits and vegetables as superfoods, implying that they are in some way more nutritious than other produce. Of course, different fruits and vegetables do indeed differ in their nutrient content. Blackcurrants and acerola cherries are extremely rich sources of vitamin C, containing very much more than strawberries or apricots. However, this does not imbue them with “super” status as part of a mixed diet.
The concept of superfoods was developed in the USA in 2003-4 and was introduced in Britain by an article in the Daily Mail on 22 December 2005. Superfoods are just ordinary foods that are especially rich in nutrients or antioxidants and other potentially protective compounds, including polyunsaturated fatty acids and dietary fibre.
Scanning through a handful of websites thrown up by a Google search for “superfoods” gives the following list almonds, apples, avocado, baked beans, bananas, beetroot, blueberries, Brazil nuts, broccoli, Brussels sprouts, cabbage, carrots, cocoa, cranberries, flax seeds, garlic, ginger, kiwi, mango, olive oil, onions, oranges, peppers, pineapple, pumpkin, red grapes, salmon, soy, spinach, strawberries, sunflower seeds, sweet potato, tea, tomatoes, watercress, whole grain seeded bread, whole grains, wine, yoghurt.
There are very few surprises in this list (apart perhaps from the inclusion of wine as a superfood, although red wine is a rich source of antioxidants, and there is some, limited, evidence that modest alcohol consumption is beneficial). Most of these are foods that nutritionists and dietitians have talked about for years as being nutrient dense – i.e. they have a high content of vitamins and minerals. The nuts, seeds, and olive oil are an exception, but they are all good sources of polyunsaturated fatty acids.
The labelling and marketing of the foods as superfoods seems disingenuous (or a clever marketing strategy), but if such marketing leads people to eat more fruit and vegetables and reduce their saturated fat, salt and sugar intake then it can only help to reinforce the message that the nutrition and public health communities have been preaching for more than a quarter of a century.
David Bender graduated in Biochemistry from the University of Birmingham in 1968 and gained his PhD in Biochemistry from the University of London in 1971. From 1968 until his retirement in 2010 he was a member of academic staff of the Middlesex Hospital Medical School, and then, following a merger, of University College London, teaching nutrition and biochemistry, mainly to medical students. He is Emeritus Professor of Nutritional Biochemistry at University College London. He is the author of Nutrition: A Very Short Introduction.
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