Nutrition Research Highlights 6|2011
6 | 2 0 1 1
This newsletter is published by the Nutrition & Health Group of the JRC’s Institute for Health and Consumer Protection. Regularly surveying the top nutrition and medical journals, we select the most recent news on nutrition research, relevant to current societal debates or policies. These are then summarized as “News” items or presented as a “View”, comprising an analysis and expert opinion. Enjoy your reading!
- To drink or not to drink (sugar sweetened beverages) ?
- Dietary supplements, who needs them?
- 7th billion and counting
1) as well as the US 2011 Dietary Guidelines (2) call for reduction in SSB consumption as a means of preventing obesity. However, the association between SSBs consumption and obesity is not without controversy, as a recent article by Weed et al (3), sponsored by a well known soft drinks multinational company, casts doubts on the quality of the studies associating SSBs with obesity. The authors evaluated the available systematic literature reviews and concluded that many studies lack methodological quality and that "in the absence of such methodological quality, conclusions shown in reviews maybe little more than informed personal subjective opinions", and should therefore not be used for policy making. The response comes from an editorial (4) by Malik & Hu (Harvard School of Public Health). They argue that, on the contrary, according to the existing scientific literature a "clear and consistent association" does exist between SSB consumption and obesity and related cardio-metabolic diseases development. In addition, Malik & Hu highlight the limitations and challenge the quality of the article by Weed et al., raising concerns about its methodological validity and misreporting of results. Malik & Hu conclude that, despite attempts from the beverage industry to create confusion by funding biased studies and by providing misleading information to consumers, there are already public health strategies designed to reduce SSB consumption, like taxation on high sugar content (already implemented in Hungary), or removal of sugary soft drinks from school canteens. Although taxation or banning (5) as "hard" nutritional policy options have yet to convincingly prove their effectiveness, the great majority of the scientific community believes that regular consumption of sugar sweetened soft drinks contributes to obesity and to related metabolic diseases. This is not really hard to grasp, taking into account that an average 330ml can has approx 140-150 calories. But what about low calorie/diet soft drinks with artificial sweeteners? Well, that is a question for another issue... For now, and to address our title, it's ok to occasional enjoy a soft drink; just don't make a habit of it (PM).
* non alcoholic beverages with added caloric sweeteners (e.g. sugar or high fructose corn syrup)
Photo: Cola drink (Wikipedia Commons)
Dietary supplements are thought to contribute to better health but, not for the first time, a recent article (1) raised concerns that their use might have some detrimental effects after all. What are dietary supplements and are they really harmful? Dietary supplements do not only refer to the ones that contain micronutrients such as vitamins and minerals, but also to those with essential fatty acids or specific amino acids and dietary fibre. The intake of dietary supplements is often intended to complement the regular diet in terms of nutrient requirements with the hope of preventing chronic diseases. Although the use of supplements in malnourished populations is beneficial for health e.g. vitamin A supplementation in malnourished children decreases the incidence of diarrhoea and measles (2), the long-term consequences of these commonly used preparations in well-nourished individuals are unknown. Despite the widespread use and the consumer beliefs regarding beneficial health effects, scientific evidence supporting efficacy seems to be lacking (3). Intensive use of dietary supplements, with varying compositions, in combination with food fortification could result in long-term high intake of individual (micro-) nutrients and might even exceed tolerable upper intake levels (such as for vitamin A and D and selenium) which vary by age and gender and tend to be lower for young children and pregnant women (4). Results from epidemiologic studies have been inconsistent and a recent long-term prospective analysis of the Iowa Women's Health Study (over 35.000 women) concluded that in older women (60+ years) the use of several commonly used vitamin and mineral supplements might even be associated with an increased total mortality risk (1). Specifically, compared to non-users, the long-term use of several multivitamins, vitamin B6 and folic acid, as well as minerals such as iron, magnesium, zinc and copper were associated with an increased total mortality risk. As discussed by the authors (1), one aspect that could have strengthened the association between supplement intake and mortality is the possibility that the supplements could be taken by people as a response to symptoms or clinical disease in an attempt to restore their health or lower the mortality risk. Other large cohort studies (3,5) concluded that the use of multivitamin supplements has little or no influence on total mortality, cardiovascular disease and common types of cancer. As these studies focus on mortality as the end point, potential benefits of supplements on well-being and quality of life were not measured. Stronger evidence will be needed to support or refute the health effects of dietary supplements in well nourished populations. In the meantime, the use of dietary supplements should be discussed with medical specialists and tailored to the nutritional needs of the individual (RG).
On Monday the 31st of October 2011 the global population reached 7 billion people. Not surprisingly, there were more than one lucky newborn that can claim that title, and anyway no-one can tell with certainty the exact number of earthlings. So in what state does the 7th billion arrival find our world, at least from a nutrition point of view? A bit grim actually…While one in five adults is overweight or obese, one in seven human beings is suffering from hunger, one in four children is underweight (1) and 209 million children under the age of 5 are stunted due to chronic malnutrition (2). These realities normally do not co-exist, as you can see from the word maps of hunger (left) and obesity (right). However, during the opening lecture of the "11th FENS* European Nutrition Conference" on 26 October 2011, Francesco Branca** warned that as developing countries start to prosper, they start suffering from overnutrition while still struggling with undernutrition. In the Middle East or the North and South of Africa, for example, the percentage of overweight children doubled in the last 20 yrs. At the same time, the world population is increasing and projected to grow to 9.1 billion by 2050. Most of this increase will occur in the developing world, and if the observed trend (i.e. towards a more western style diet high in animal protein) in the nutritional habits of the developing world does not change, 70% more food than what we are currently producing will be required to feed the world (3). Food security (in brief, sufficient access to food) though is a rather complex issue, and there are different diverging opinions on whether we have or not enough food to feed the world (4). Nevertheless, the fact that 1 billion people worldwide, twice the population of the European Union, is suffering from hunger and that the world's resources including food and arable land are not unlimited should make us reflect on our current practices: eat too much and unsustainable amounts of animal proteins, waste unacceptable high amounts of food, and (mis)use arable land for biofuels or green chemistry, to name just a few food related issues. And maybe these reflections should not just happen while approaching Christmas but they should be translated into actions all year long...(PM)
**Director of the Department of Nutrition for Health and Development, WHO
Images: Left: World hunger (World Food Programme); Right: World map of overweight and obese (WHO)
As the year's end is approaching, have you thought about your New Year's resolution? Stop smoking? Exercise more often? Drink or eat less? In particular, eat less of goodies such as chocolate, ice cream, potato chips etc? Why do we do this? Or asking a more inconvenient question when looking back at our last year's New Year's resolution: why do we often fail to abide by our 'healthy' resolutions and find ourselves saying, like Homer Simpson: "D'oh! Why did I do that?"
One may find sympathy for some little self-indulgence and believe that it does not do much harm. So let's look at behaviour and its impact first. What starts as an individual choice can become quite dramatic if considered at the population level: a recent study in the UK has found that more than 40% of all cancers that occurred in 2010 could be attributed to modifiable lifestyle and environmental factors, with tobacco (19.4%), poor diet (9.2%), overweight and obesity (5.5%) and alcohol abuse (4%) accounting for the great majority of all those cases (1). Similar numbers can be expected for other chronic diseases (for example heart disease, stroke or diabetes) in other industrialised countries as well as, increasingly, in emerging economies. Last September, New York hosted many state leaders for the first ever UN General Assembly on noncommunicable diseases (NCDs), a group of chronic non-infectious diseases, such as cardiovascular disease, cancer, chronic lung diseases and diabetes, that are largely preventable by avoiding their four main behavioural risk factors: tobacco, alcohol abuse, unhealthy diets and physical inactivity (2, 3). A main reason for NCDs moving up on political agendas is that NCDs not only account for almost two-thirds of all global deaths, one fourth of which occur before the age of 60, but because they are also considered a threat to economic growth and development (4, 5). This is due to the social burden coming with NCDs, including not only direct health care costs but also losses due to diminished resources within families, prolonged disability, reduced productivity and capital formation.
Back to our New Year's resolutions…When asked, most people will state that they wish to remain healthy, have a healthy weight, exercise regularly and eat healthily, quit smoking and drinking or use the car less. But their subsequent actions are often inconsistent with these wishes. The traditional economics theory says that humans, as rational beings, make choices to maximize their utility in full awareness of the consequences of their decisions and therefore there would be no reason to intervene: people do what they are most happy with. But that stands in striking contrast to the observation that many obese people state that they would prefer a healthier life style.
It seems that people do not always (manage to) act according to their true preferences or maximum benefits. This is also suggested by behavioural economics, a field that has recently gained much attention and is finding its way into policy. Behavioural economics delivers empirical evidence on how people actually make decisions and why people often fail to act in their own (long term) best interest. Indeed, humans are not always rational but are prone to biases, make mistakes in thought processes and use rules of thumb that lead to sub-optimal decision making. In addition, people's decisions are often inconsistent in time due to inertia, lack of willpower or self control (6, 7). In our example, the hedonic pleasures from eating, smoking, drinking and lazing around outweigh the individual burden from chronic diseases, prolonged disabilities, or the feeling of being a burden on the family, friends or the society only because the former come immediately and the latter far later in life.
So, we apparently share our time inconsistency or lack of self control with many others, but what can be done? In contrast to the libertarian 'the-free-market-resolves-it-all' approach stands the hard paternalistic approach, one that restricts choice through legislation, banning or taxation. While the society may more readily agree to restrictive legislation on smoking or hard liquor, especially for protecting adolescents, when it comes to food, there is far less acceptance of restrictions. Food restrictions would touch our traditional Christmas roast or biscuits, salty pretzels, beer and wine, wholemeal bread and many traditional foodstuffs in our culturally rich European continent. Filling the gap, a third policy approach is finding its way into national and European policies, building on behavioural economics to design better policies for consumers that need help to overcome their self-defeating decisions while still leaving the final decision to the citizen. Its most prominent names are libertarian paternalism or 'nudging' (7). In short words, nudging is not restricting choice or prescribing a choice selected by politicians or scientists for the citizens, it is about assisting people in finding their true preferences. Thus, a 'nudged' person achieves better results, in particular while choosing in an 'impaired rational mode', and as judged by the person himself when reflecting more thoroughly on his/her true preferences. A person that does not wish to follow the nudged option can still do so with little or no costs compared to hard paternalistic approaches where high taxes or other deterrents are to be faced.
There are already initiatives that show how the insights from behavioural economics can be effectively used to counter the overweight/obesity problematic. For example, student cafeterias have been redesigned to promote more healthy meal compositions, such as through putting nutritious foods more to the front and present them in a more attractive way (behavioural economics call this the "framing effect") (8). Offering smaller portion size has been demonstrated effective in reducing energy intake (9). Committing to others that we will get slimmer is an effective way for overweight individuals to reduce weight (10). Physical activity rates can be increased by providing immediate reward to overcome the short-term hassle that comes with physical activity. Examples are the fun people have when walking up "piano stairs" instead of escalators (11), or through online gaming and tracking that motivates children to walk to school (12).
Of course for us as individuals this does not mean we have to wait for smart politicians to provide us with a series of nudges to better comply with some of our New Year's resolutions. Being more conscious of the fact that at times we operate with an 'impaired rational mode' when making our decisions and knowing in what situations it prevents us from achieving our true preferences can already help reducing the number of occasions we make poor (seen from a distance or retrospectively) decisions. For example, when you know you are often taking too much food or too many 'pleasures' during lunch, plan your lunch ahead of time and try to stick to what you planned later when taking the dishes. If you are great in procrastinating your plan to exercise, committing to a friend, fixed exercise appointments, social networks or electronic gadgets showing energy consumption or training progress help greatly for overcoming one's weaker self.
There is of course no reason why we should not enjoy from time to time some of the temptations offered to us. However, we better enjoy them consciously when we truly wish to do so, and not accidentally. Like this we can have the cake and enjoy at times the immediate pleasure and not impairing our long-term true objectives. Doh! Why didn't I think of this earlier? (JW)
Nutrition Research Highlights is a bi-monthly publication prepared by the Nutrition Team of the DG-Joint Research Centre, Institute for Health and Consumer Protection. The Nutrition team is comprised of Sandra Caldeira, Raymond Gemen, Petros Maragkoudakis & Jan Wollgast.
The views expressed here do not necessarily reflect the opinion of the European Commission.
© European Union, 2011. Reproduction of articles (excluding photographs) is authorised, except for commercial purposes, provided that the source is mentioned.