Goji berries, chia seeds, kale: Reputed for their beneficial effects, these foodstuffs are proving popular, but do they deliver on their promises?
Superfood – a fast-growing trend. ©Shutterstock/Signe Leth
In China, their native country, goji berries are known as the ‘fruit of longevity’. These small, elongated, sweet red berries are said to boost the immune system, reduce blood pressure and improve libido. Fans of goji berries believe they possess a host of other qualities, including positive effects on the liver, memory, vision, fertility, digestion, and even the mind.
Goji berries are undoubtedly one of the stars among superfood, products reputed for their beneficial effects on health. Other superfood includes acai berries, packed with vitamins and native to the Amazon, and chia seeds, a type of Mexican sage rich in omega-3. Until a few years ago, superfood was unknown in Western countries, but it has since become a firm fixture in organic and health food stores, before finding its way to the aisles of mainstream supermarkets. Yet superfood is no longer limited to a few exotic foodstuffs. More and more fruit and vegetables that grow in our climates are now being awarded this accolade. These include bilberries, broccoli and beetroot.
Symbolism and imagination
“The concept of superfood is rather ingenious,” observes Éric Birlouez, a French sociologist and food historian who teaches at Lille 1 and Paris-Descartes universities. “It evokes very positive images of superheroes and superpowers, rather than health and medicine.” This expert believes that the trend, which began in California at the beginning of the millennium, particularly appeals to consumers in a context of increasing concern about food.
“The processed products of the food industry, and the idea that they have lost some of their goodness in the factories, arouse mistrust. On the contrary, superfood embodies a certain naturalness. It has a ‘corrective’ role and comes across as an easy way of compensating for an industrial diet.” Almost all superfood comes from the plant world, another popular aspect at a time when vegetarianism and veganism are gaining ground.
Éric Birlouez also points out that the exotic dimension of some superfood constitutes an important factor in its success. “The fact that it comes from the Amazon rainforest or the Tibetan plateau gives it a particular aura. This phenomenon is as old as the hills! Already in the 14th and 15th centuries, rich people used to eat spices, not for their taste but, since they came from far away and were expensive, they believed they were good for their health. Superfood still has a story to tell – that of indigenous peoples spared from modern diseases, who have been growing it and eating it since time immemorial. We are entering the realm of dreams, symbols and imagination.”
Christine Schäfer, from the Gottlieb Duttweiler Institute, a think tank based in Rüschlikon near Zurich, draws a parallel between superfood and the growing desire to lead a healthy lifestyle, with plenty of self-quantifying and ‘self-optimisation’. “Modern people count how many steps they take, the number of calories they burn and the amount of nutrients they ingest, and superfood seems to facilitate this process. We also need to take into account the influence of social networks and celebrity blogs which extol the merits of such food.”
On the face of it, the trend of eating fruit, vegetables and plants, reputed to be particularly healthy, should delight doctors and nutritionists. However, health professionals are somewhat cautious. Firstly, there is no scientific definition of superfood – the term is simply marketing lingo. “Some foodstuffs do have particularly interesting properties, but there is no clear distinction between what we consider to be ‘normal’ food and what is ‘superfood’,” explains Dimitrios Samaras, a consultant at the nutrition unit of Geneva University Hospitals. “In fact, it is forbidden to mention this word on food packaging for the European market.”
“It has been established that a diet rich in fruit and vegetables is good for our health,” states Olivier Potterat, a specialist in edible and medicinal plants at the University of Basel. However, superfood conveys the idea that there are miracle plants which should be favoured over others, which is simply not true.”
The fact that such or such a product is promoted to the rank of superfood is based on scientific studies, some of which has been published in well-respected journals such as The American Journal of Clinical Nutrition or the British Journal of Nutrition. There is evidence, for example, that bilberries, rich in antioxidants, slow down the growth of cancerous cells in the bowel1 and have a reparative effect on memory loss due to old age2. Pomegranates provide another example; studies have shown that, in the short term, they can reduce blood pressure3.
However, the conclusions we can draw from these studies must be treated with caution. As the European Food Information Council (EUFIC) points out, they are difficult to apply in reality. This non-profit organisation based in Brussels, financed by the agro-food industry and the European Commission, puts forward several criticisms: The food is examined in isolation, the amounts are not realistic in the context of a normal diet and most of the studies are carried out on animals or on human cells in vitro.
Beware of pesticides
“The effects of a foodstuff often appear over the long term and some of these play a protective role. However, it is difficult to carry out very long-term clinical studies,” continues Olivier Potterat, from the University of Basel. “Furthermore, food does not consist of pure substances, in the way that medication does, but of a mix of thousands of substances which act together on the organism. Even if there are good reasons to believe that eating certain kinds of fruit or vegetables is particularly good for the health, the exact effects are difficult to prove.” It is also necessary to distinguish between the consumption of actual fruit or vegetables and that of some of their constituents in the form of food supplements. The scientist cites the case of beta-carotene, found in carrots. Epidemiological studies suggest that a diet rich in carotene could reduce the risk of cancer. However, two major clinical studies have revealed that taking purified beta-carotene capsules actually led to an increase in cases of lung cancer in heavy smokers4.
There is also an additional misgiving as to the real benefit of superfood: the presence of pesticides. As Olivier Potterat points out, “Certain products, particularly those from exotic countries, are sometimes heavily contaminated.” In this case, the risk is that any positive effect to be gained from consuming them will be considerably offset.” In the late noughties, when goji berries were at the height of their popularity in Europe and the United States, they became embroiled in considerable controversy. They were produced in China in somewhat dubious conditions, resulting in higher levels of pesticides than those authorised.
However, Dimitrios Samaras, from Geneva University Hospitals, refuses to reject the concept completely. “We must remain pragmatic. Superfood – 99% of which is plant based – generally contains nutrients which are good for everybody. Currently, around 30% of the Swiss population does not eat the recommended five servings of fruit and vegetables a day. In the United States, this proportion is as high as 45%. Governments have been campaigning about this for the past twenty years, but have not yet reached their objectives. Of course, the idea should not to be misconstrued: We must not think that consuming superfood allows us to eat more unhealthy foodstuffs. If it is communicated intelligently, the concept can encourage people to adopt a diet with more fruit and vegetables. This is a good thing, so why not use it?” It is also important to emphasise that superfood does not necessarily need to be expensive or exotic, as numerous local equivalents exist, such as flaxseed, broccoli, bilberries, cranberries, raspberries, spelt and buckwheat. Superfood can thereby act as a spearhead for promoting the consumption of a wide variety of fruit and vegetables.