In the last issue of Nutraceutical Business Review, when GOED reported on the Codex effort to establish a Nutrient Reference Value (also known as a recommended intake) for EPA and DHA, we mentioned the potential controversy, particularly in Canada and the United States, associated with using chronic disease risk reduction endpoints to establish recommended intakes.
Since that article was published, the Dietary Reference Intake (DRI) Committees of the Canadian and US governments held a 2-day workshop to discuss the use of chronic disease endpoints, such as cardiovascular disease, for setting DRIs.
Going into that workshop, GOED thought it would end with a recommendation for whether or not chronic disease risk reduction could be used as an endpoint to establish DRIs. But, it quickly became evident that the purpose of the workshop was not to come to consensus, but rather to inform the governments of the US and Canada about the issues associated with using chronic diseases as endpoints. Based on the issues raised in the workshop, it is clear that the governments are far from making up their minds!
The process to establish a DRI for EPA+DHA in Canada and the United States has been long and slow. In September 2009, GOED and eight other organisations submitted a citizen’s petition to the Institute of Medicine (IOM) to ask for a DRI review for EPA and DHA, which included an analysis of EPA and DHA’s role in chronic disease risk reduction within the DRI framework. At the time, no process existed to systematically initiate DRI reviews, so a citizen’s petition was the only option. However, in March 2013, the US and Canadian governments issued a call for DRI nominations, establishing a process for the first time.
GOED nominated EPA and DHA because the body of scientific evidence supporting the role of EPA and DHA in human nutrition has seen precipitous growth since 2001, the date of the last EPA/DHA study cited in the 2005 DRI report that included fatty acids.1 Since that time, many authoritative bodies, including the European Food Safety Authority and expert scientific groups, have issued their own EPA+DHA intake recommendations.2
The main challenge is that DRIs in the US and Canada are traditionally based on their role in deficiency diseases such as dermatitis or scurvy, and much of the research on omega-3s has been in chronic diseases such as cardiovascular disease (CVD).
Chronic disease endpoints are being used in other countries and regions globally to establish DRIs and DRI-like intake recommendations. Both the Public Health Agency of Canada and the US Centers for Disease Control and Prevention continue to report a rapidly growing burden of chronic disease, so chronic diseases are of concern to both governments.
By 2020, nearly 75% of all deaths and 60% of all disability adjusted life years worldwide will be attributable to non-communicable chronic diseases including, among others, cardiovascular diseases.3 Most of these burdens occur prematurely and can be prevented or delayed, making the identification and targeting of the modifiable risk factors with greatest impact on these diseases among the greatest health priorities of our time.
Evidence of risk reduction
Specific to EPA+DHA, there is a wealth of scientific evidence supporting their benefits for the risk reduction of cardiovascular disease in the general, healthy population. Globally, in 2010, the attributable burden of a diet low in seafood (rich source of EPA+DHA) was 1.1% of global disability adjusted life-years (DALYs; 95% CI 0.8–1.5), with 22% of ischaemic heart disease DALYs attributable to low seafood intake.4,5 In the United States, low dietary omega-3 (EPA+DHA) intake accounts for 72,000–96,000 deaths per year from CVD.6 In addition, EPA+DHA have been shown to be associated with a lower total mortality, translating into living an extra 2 years or more.7GOED recognises that, unlike the effectiveness of reducing the risk of a nutrient deficiency, chronic diseases are not nutrient specific, rather multifactorial, with other factors, such as genetics, age, environment, lifestyle and other nutrients, contributing to the risk. However, that chronic diseases are not nutrient specific does not negate the importance of providing the best possible nutrition advice. To achieve the best results in preventing chronic diseases, the strategies and policies that are applied must fully recognize the essential role of diet, nutrition and physical activity.8
Similar to other vital nutrients, establishing a clear DRI for EPA+DHA would allow both public and private initiatives to help educate the population about intake levels sufficient for reducing the burden of chronic diseases. It should be noted that, in the past, establishing risk levels has helped to launch a series of public and private initiatives to reduce tobacco usage and sodium intakes. The same should be true for establishing risk reduction levels for vital nutrients that currently have no clear DRIs.
Lack of focus
The workshop did not focus on EPA and DHA specifically, but it was concerning to GOED that many of the issues identified to use chronic disease endpoints for establishing DRIs were based on the experience with individual nutrients, rather than with the level of evidence necessary to establish a DRI. For example, there was a dispute about whether biomarkers of intake exist for nutrients based on the inability to find one for vitamin D.
For omega-3s, there are a number of markers of both short- and long-term intakes, so delaying the development of a DRI framework because of one nutrient could have widespread public health implications owing to low intakes of another nutrient. These and other similar issues raised in the workshop made it clear to GOED that the timeframe for commencing a DRI review will not be revealed until at least the beginning of 2016.
References
1. Food and Nutrition Board, Institute of Medicine of the National Academies, Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids (The National Academies Press, Washington, DC, USA, 2002/2005): www.nal.usda.gov/fnic/DRI/DRI_Energy/energy_full_report.pdf.
2. EFSA Panel on Dietetic Products, Nutrition, and Allergies (NDA), 'Scientific Opinion on Dietary Reference Values for fats, Including Saturated Fatty Acids, Polyunsaturated Fatty Acids, Monounsaturated Fatty Acids, Trans Fatty Acids and Cholesterol,' EFSA Journal 8(3), 1461 (2010): www.efsa.europa.eu/en/efsajournal/doc/1461.pdf.
3. C.D. Mathers and D. Loncar, 'Projections of Global Mortality and Burden of Disease from 2002 to 2030,' PLoS Med. 3(11), e442 (2006).
4. R.E. Engell, et al., 'Seafood Omega-3 Intake and Risk of Coronary Heart Disease Death: An Updated Meta-Analysis with Implications for Attributable Burden,' Lancet 381, S45 (2013): www.thelancet.com/journals/lancet/article/PIIS0140-6736(13)61299-4/fulltext.
5. S.S. Lim, et al., 'A Comparative Risk Assessment of Burden of Disease and Injury Attributable to 67 Risk Factors and Risk Factor Clusters in 21 Regions, 1990–2010: A Systematic Analysis for the Global Burden of Disease Study 2010,' Lancet 380, 2224–2260 (2012).
6. G. Danaei, et al., 'The Preventable Causes of Death in the United States: Comparative Risk Assessment of Dietary, Lifestyle and Metabolic Risk Factors,' PLoS Med. 6(4), e1000058 (2009).
7. D. Mozaffarian, et al., 'Plasma Phospholipid Long-Chain w-3 Fatty Acids and Total and Cause-Specific Mortality in Older Adults: A Cohort Study,' Ann. Intern. Med. 158, 515–525 (2013).
8. WHO/FAO (World Health Organization and Food and Agriculture Organization), Expert Report: Diet, Nutrition and Prevention of Chronic Diseases. Report of a Joint WHO/FAO Expert Consultation. WHO Technical Report Series 916 (2003): http://whqlibdoc.who.int/trs/who_trs_916.pdf.
