Nutrition Research Highlights 2|2013
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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!
Most people avoid thinking about death and disease. However, by knowing, quantifying and comparing death, disability and risk factors around the world, one can guide public health efforts to prevent disease and injuries or to mitigate and prepare for their consequences. The Global Burden of Disease 2010 (1) (the series of articles on GBD2010 has been published here) did just that. It was a major study that brought on board 486 scientists from 302 institutions in 50 countries to map health and disease on the globe. The results? As with a half-full or half-empty glass there are different ways of looking at the data. It is good news that infectious diseases (apart from HIV/AIDS), maternal and child illness, and malnutrition kill fewer people now than they did twenty years ago. Although they are still claiming lives and should remain high on public agendas, the major causes of death and disability are now non-communicable diseases, such as heart disease, the number 1 killer on this sad podium. The fastest growing major illness is diabetes with roughly double the deaths than it had in 1990. If you are a frequent reader of our pages the next lines will not come as a surprise to you. Topping the risk factors for all the deaths and disabilities accounted for in this study are of course dietary factors. The figure presented here on the left details the top 20 risk factors and the burden of disease they are associated with [click on this link to visualise the interactive graphs]. Fifteen out of these 20 are directly or indirectly related to nutrition and physical activity. There is half full or empty glass here too. Public health actors have a good basis for future work by focusing on these risk factors. And we as individuals can act on it too as these factors are modifiable and to a large extent preventable. While it may not always be easy to change behaviours, small steps are in everyone's reach and little by little can have an effect.. We can turn these numbers round! (SC)
Image: Burden of disease attributable to 20 leading risk factors in 2010, expressed as a percentage of global disability-adjusted life-years for both men and women. Reproduced from The Lancet, 380, 9859, 2013, pp.2224–2260 (1) with permission from Elsevier.
The role nutrition plays in an individual's health is very clear. Should there be any doubts, please read our article above. While the relationship between nutrition and health has been studied for around two centuries, it is only in the past two decades that a new approach has emerged to link nutrition with the efficiency of health resources allocation*. Due to the escalating healthcare costs, decision-makers have focused on a new approach in the field of nutrition: nutrition economics (1).
This sub-branch of health economics was defined in 2010 as "a discipline dedicated to researching and characterising health and economic outcomes in nutrition for the benefit of society"(2). This means that an appropriate diet should not only improve the health of a society but to also reduce health care costs and improve quality of life. To make the concept clearer, let us consider a concrete and very recent example of a nutrition economics analysis. Lotters and colleagues estimated the impact of increasing dairy products (low-fat milk, yogurt, fresh cheese and cheese) consumption as a calcium source on reducing the osteoporosis-related hip fractures in France, the Netherlands and Sweden (3). First, the authors calculated the number of hip fractures which could potentially be prevented with an increased intake of dairy products to ensure 1300 mg calcium per day (as recommended by the International Osteoporosis Foundation (4)) in a population of women and men aged 50 or over. Then, the costs avoided from the reductions of the number of hip fractures and the number of DALYs** (disability-adjusted life years) were calculated for the whole life of the patient cohort. The model shows that, for example, in France, increasing dairies consumption to reach the dietary calcium recommendation would prevent 2,023 hip fractures. This means extra 3 years of life without disability per person and a cost saving to France of 6 million euros. Additional studies such as this one, will aid in further assessing not only health but also economic and social effects of specific dietary practices – important arguments among others in public health in current times! (CMS)
*"Health resources allocation" refers to the way decision-makers decide where to spend the constrained budget of health care costs.
**DALYs is a way to measure the number of years people lose because of premature disease-related dead and also account for the number of years lived without "healthy" life due to the disease.
Salt has hit the headlines again. Three recent articles brought forward the hypothesis that salt may be implicated in the development of autoimmune diseases* (1, 2, 3). Two of the studies place salt in a pathway that stimulates production of a particular type of immune response cells called TH17**. These cells have been implicated in the pathogenesis of some autoimmune diseases. Indeed, the studies showed that in mice, a high salt diet accelerated the progression of an autoimmune disease similar to multiple sclerosis (2, 3). Whether these findings will hold true for human forms of the disease or in other types of autoimmune disease is not yet clear. Nevertheless, the hypothesis clearly deserves more attention and further studies because the last 50 years have seen an increase in the incidence of these types of disease (3). Given the links between salt intake, blood pressure and cardiovascular disease and the high intake of salt in most of the developed world, many countries have started to react and have ongoing or planned salt reduction initiatives (4, 5). In Europe, the salt reduction initiative has been one of the most noted achievements of the "Strategy for Europe on nutrition, overweight and obesity related health issues" (6) and the potential of findings such as the ones discussed here strengthen the relevance of such efforts. (SE)
*Diseases in which the immune system attacks an organism’s own tissues (eg Type 1 diabetes or multiple sclerosis)
**Immune blood cells that produce an inflammatory protein called interleukin – 17 and aid in the clearing of extracellular pathogens
Life expectancy has been increasing over the last 150 years (1), due to factors such as improved health care and increased standards of living through rapid social and economic developments. Globally, the number of older adults aged 65y+ is predicted to outnumber children under the age of 5y in the next five years (2).
While it is all well and good that we are living longer, there are inevitable challenges associated with ageing. Over time, physical and mental health will deteriorate and the risk of developing chronic diseases (including cardiovascular diseases, diabetes and cancers) will increase. These age-related problems are likely to affect the quality of life of individuals in later years, as well as adding pressure to infrastructures such as health and social care services. In the EU-27, the population of aged 65y+ stands at 87 million, equivalent to around 17% of the whole population (3); these numbers are set to rise further, particularly in the proportion of older adults aged 80y+ (4). As a result, there has been a rapid drive to encourage healthy active ageing across Europe as well as worldwide. The European Commission has marked the year 2012 as the European Year for Active Ageing and Solidarity between Generations, and through the scheme "European Innovation Partnership on Active and Healthy Ageing", it aims to increase the average healthy lifespan of Europeans by 2 years by 2020 (5). At the global level, the WHO has also dedicated the theme "Ageing and Health" for the 2012 World Health Day. Such actions have begun to bring attention to the challenges associated with ageing, to promote information campaigns and activities for healthy ageing, and to urge health authorities to elicit action plans to manage ageing populations (2, 6).
While genes are deemed important in determining how well we age, studies on twins have indicated only around 25% of longevity is attributable to hereditary factors – a very moderate effect (7, 8, 9). On the other hand, lifestyle and environment factors, in particular diet, are shown to be crucial determinants for successful ageing. Similar to the rest of the population, older adults are recommended to eat balanced diets and be physically active. However, with the physiological changes that occur with ageing, older adults will have special requirements for certain nutrients on top of the usual requirements for the general adult population. Specific dietary recommendations or guidelines for older adults within the EU are not easy to find however. In the US, the Dietary Guidelines for Americans 2010 have made general dietary recommendations as well as recommendations on specific nutrients for adults over the age of 51y, including to lower sodium intake and to increase vitamin D and B12 intakes* (10). High sodium intake is related to high blood pressure and reducing intake is likely to reduce the risk of cardiovascular diseases, such as stroke (11) (see our article on salt and autoimmune disease and views on salt for further information). Vitamin D plays an important role in calcium absorption and is vital for bone health. Deficiency in vitamin D is a major risk factor for conditions such as osteoporosis, leading to hip fractures and falls that are commonly seen in the elderly. The primary source of vitamin D comes from sunlight, but because older people have a reduced capacity to absorb vitamin D through their skin, dietary vitamin D is needed to boost their status through sources such as oily fish, meat and fortified fat spreads (4). Vitamin B12 has an important function on the brain and nervous system, alongside with two other B-vitamins – B6 and folate. Although research on these vitamins in relation to ageing is still in its infancy, some studies have suggested that low level of plasma B12 could be associated with Alzheimer's disease and mild cognitive impairment (12). The table below highlights the food sources of important nutrients needed for older adults.
The key to a healthy ageing process is to maintain a balanced diet with a wide variety of foods, paying special attention to these nutrients to avoid deficiencies (vitamins D, B12, B6 and folate). In terms of the evidence on food consumption and health outcomes in older adults, the number of large scale prospective studies is currently limited. However, the results so far are encouraging, providing new insights into how important our diet is for successful and healthy ageing. For example, it has been found that high fruit and vegetable consumption was protective for bone health in older men (13); those with high Mediterranean dietary pattern scores** had lower overall mortality after 7.4y of follow up (14); and a dietary pattern consistent with high amounts of vegetables, fruit, whole grains, poultry, fish, and low-fat dairy products predicted better nutritional status, quality of life and survival in old age adults (15). Several reviews have also highlighted the potential protective effects of fish consumption and foods high in antioxidants (vitamins C and E) as well as B vitamins on cognitive health, such as the risk of vascular dementia and Alzheimer’s disease (16, 17).
To conclude, we cannot deny the importance of nutrition on healthy ageing and the prevention of age-related chronic diseases. While the potential of successful and healthy ageing is out there, there is still plenty to do. Firstly, more research is needed, including lifestyle interventions such as dietary changes in older people and the effects on delaying or preventing ageing-related conditions (18). Secondly, there is a need for a set of specific dietary recommendations that is easy to follow for older adults within the EU. Last but not least, as the old saying goes – prevention is always better than cure – we all have a role to play for the future and it is never too late to start with a balanced nutritious diet to embrace the healthy ageing process! (TNM)
* Dietary Guidelines for Americans 2010: To reduce the intake of sodium to 1300mg/d for adults aged 51-70y and 1200mg/d for those aged 71y+; to increase vitamin D intake to 800IU/d for the 71y+; and to consume foods fortified with vitamin B12 or from supplements.
** A high Mediterranean dietary pattern score reflects a Mediterranean diet of high intake of vegetables, legumes, fruits, and cereals (in the past largely unrefined); moderate to high intake of fish; low intake of saturated lipids but high intake of unsaturated lipids, particularly olive oil; low to moderate intake of dairy products, mostly cheese and yogurt; low intake of meat; and modest intake of ethanol, mostly as wine.
Image: Nutrients and Food sources (US National Institute of Health, Office of Dietary Supplements http://ods.od.nih.gov/factsheets/list-all/)
March - April 2013
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. Sandra Caldeira, Sandra Eisenwagen, Carlos Martin Saborido, Theodora Mouratidou, Tsz Ning Mak and Jan Wollgast contributed to this issue.
The views expressed here do not necessarily reflect the opinion of the European Commission.