By Christopher Radlicz
Currently, only one-quarter of pregnant women in the United States are eating the amount of fish recommended for optimal maternal and child health (1). On the other end of the spectrum, about 10% of women of childbearing age have higher than recommended blood mercury concentrations (2).
A qualitative study done in 2010 has helped explain why women may be consuming less than the recommended two-servings of fish per week (1). Pregnant women in the Boston area, who under-consumed fish according to these guidelines, were broken into focus groups and discussed what was keeping them from eating more fish. These groups revealed that many women knew that fish might contain mercury, but were naïve of the fact that fish contained beneficial fatty acids, such as docosahexaenoic acid (DHA), which is essential for optimal fetal brain development (3). The women admitted that they hadn't received advice to eat more fish or more specifically to eat fish that contain lower amounts of mercury and higher amounts of beneficial fatty acids. Instead, the women confessed that they were advised to limit fish intake due to possible mercury exposures.
Are these women misguided in keeping their fish consumption below the recommended two-servings per/week during pregnancy?
This past February, The 2015 Dietary Guidelines Advisory Committee reiterated that women who are pregnant, nursing, or are planning to become pregnant should still consume fish because neither the risk of mercury nor other organic pollutants outweigh the benefits (4). In a recent New York Times article on the issue, Dr. Steve Abrams, medical director of the Neonatal Nutrition Program at Baylor College of Medicine and panel member on the advisory committee commented on tuna consumption, explained, “The benefit of having (omega-3 fatty acids) in your diet really exceeds the likely risk of contamination. The point is that you should have a variety of types of seafood and not limit yourself to one type, and variety includes canned tuna.”(5).
The intake of fish during pregnancy is certainly more nuanced than simple elimination from the diet due to potential mercury exposure. Fish contains essential nutrients proven to have beneficial effects on brain neurodevelopment and may prevent cardiovascular disease (6). These benefits have been attributed in part to the long chain polyunsaturated fatty acids (LCPUFAs), DHA and eicosapentaenoic acid (EPA), but in addition seafood is a good source of protein, selenium, iron, iodine, choline, and vitamins E and D (4,7). These LCPUFAs are essential throughout pregnancy but are critical from the beginning of the third trimester until about 18 months after birth when the human brain is growing the fastest. Neglecting to supply LCPUFA among other nutrients during this period may result in deficits in brain development (9).
That being said, mercury exposure is a real possibility. Methylmercury is the organic form of mercury that we are exposed to when consuming fish in our diet. This form of mercury is relatively stable, mobile within the body, and exhibits a high potential to damage the brain (8). Mercury poisoning outbreaks in Japan are a testament to the wide spread damage that can occur from exposure to methylmercury, resulting in infants born with serious neurological damage, even when mothers were seemingly unaffected (10).
Extreme exposure to mercury in the food chain as in the case of Japan is a rather isolated instance though. But what is the balance? Do the beneficial effects of fish counteract the adverse effects of toxicants?
In the literature, detection of methylmercury exposure in infants is typically done by measuring levels in maternal hair, maternal toenails, cord blood, and maternal blood. These methods are variable in measuring biomarkers and on certain occasion, can be imprecise (5,7). Additionally, many observational studies do not statically control for negative confounders. This means that majority of the cohort studies done in this field have focused on either the risk of methylmercury or on nutrient benefits but not both (7).
All of the complications in study design and analysis show the complexity of establishing recommendations from these studies. Even with good study designs, clear-cut recommendations as to how much fish pregnant women should eat may still not be feasible, due to the variability of toxicants in seafood species. Empowering pregnant women by informing them of seafood that is lower in mercury levels and higher in LCPUFAs is a practical solution. A pertinent rule to apply when making seafood choices is that small sea creatures, which live shorter lives and are lower on the food chain, tend to be the lowest in methylmercury levels and exponentially higher in LCPUFAs. Larger seafood, on the other hand, tends to have higher levels of methylmercury due to a longer lifespan and their higher settlement on the food chain allowing for an accumulation of more methylmercury. The Dietary Guidelines Advisory Committee is in consensuses with the FDA and EPA in advising pregnant women to avoid eating these larger fish, such as swordfish, tilefish, shark, and king mackerel due to their high levels of methylmercury (4,7).
1.Bloomingdale A, Guthrie LB, Price S, Wright RO, Platek D, Haines J, Oken E. A qualitative study of fish consumption during pregnancy. Am J Clin Nutr 2010; 92: 1234-40. doi:10.3945/ajcn.2010.30070
2.Mahaffey KR, Clickner RP, Bodurow CC. Blood organic mercury and
dietary mercury intake: National Health and Nutrition Examination
Survey, 1999 and 2000. Environ Health Perspect 2004 ;112:562–70.
3.Koletzko B, Cetin I, Thomas Brenna J. Dietary fat intakes for pregnant
and lactating women. Br J Nutr 2007;98:873–7.
4.United States Department of Agriculture. Scientific Report of the 2015 Dietary guidelines Advisory Committee. Washington, DC. 2015.
5.Parker-Pope T. (2015, March 2). Should Pregnant Women Eat More Tuna. The New York Times. Retrieved from http://www.nytimes.com. http://well.blogs.nytimes.com/2015/03/02/should-pregnant-women-eat-more-tuna/?r=0
6.Anon. The Madison Declaration on Mercury Pollution. Ambio 2007;36:62–65. [PubMed: 17408191]
7.Choi AL, Cordier S, Weihe P, Grandjean G. Negative Confounding in the Evaluation of Toxicity: The Case of Methylmercury in Fish and Seafood. Crit Rev Roxicol. 2008; 38: 877-893. doi:10.1080/10408440802273164.
8.Clarkson CW, Vyas JB, Ballatori N. Mechanisms of Mercury Disposition in the Body. American Journal of Industrial Medicine 2007;50:757-764.
9.Innis SM. Essential fatty acids in growth and development. Prog Lip Res 1991; 30: 39.
10.Harada M. Minamata Disease: Methylmercury Poisoning in Japan Caused by Environmental Pollution. Crit Rev Toxicol 1995;25:1–24.
11.Hibbeln JR, Davis JM, Steer C, Emmett P, Rogers I, Williams C, Golding J. Maternal seafood consumption in pregnancy and neurodevelopmental outcomes in childhood (ALSPAC study): an observational cohort study. Lancet 2007;369:578–585.
By Marion Roche, PhD
Approximately162 million children are stunted.In the global nutrition community the human costs of stunting are well recognized: stunted children complete less school, have less learning and earning opportunities, and females who become moms in the future are more likely to give birth to stunted children. Intervening early in 1000-day window (from conception to the age of two) and even earlier, pre-pregnancy, is recognized as most cost-effective way to prevent, as in many settings it challenging to reverse the physical and cognitive deficits from chronic malnutrition. Beyond the human costs, there is also an economic case to be made for investing in stunting reduction.
Every four years, the world's leading economists and experts from diverse development fields come together to rank the best investments for development in what is called the Copenhagen Consensus. Nutrition is one such investment that is consistently ranked as a “best buy”. Specific interventions such as vitamin A supplementation, salt iodization, zinc & ORS for diarrhea treatment and support for breastfeeding and adequate complementary feeding have all been in the top 10 best investments in previous years. In addition, nutrition-sensitive approaches, such as keeping girls in school, improvements to agriculture yields and crop quality, enabling gender equity for women, and overall poverty reduction, are all necessary to sustainable long-term stunting reductions for communities and countries.
This month, world leaders and experts met in Addis Ababa, Ethiopia for the Third International Financing for Development conference. A presentation by Dr. Meera Shekar of the World Bank and Dr. Robert Hetch of Results for Development at an MI co-hosted side-event on nutrition at the conference laid out what it would take to achieve the World Health Assembly target of reducing stunting by 40% by 2025. They emphasized that strategic investing in improving the nutrition situation for 68 million children would offer a long-term $45 dollar return on each dollar invested. More specifically, every dollar invested in reducing stunting is estimated to generate an $18 return in the long run. However, although many nutrition interventions look affordable on an individual scale, a more detailed analysis has been done to show what it would cost to deliver these interventions and reduce stunting at a global scale.
The Financing for Development conference was centred on funding the Sustainable Development Goals, the set of targets relating to the of future international development post-2015. Looking at the return on investment (ROI) in nutrition and knowing that nutrition has such a profound effect on other areas of a person's life, I think there is no better investment the world can make to reach the SDGs more quickly and effectively than that in nutrition!
Breakfast is often considered the “most important meal of the day,” and if you are looking to lose weight, you mustn't skip breakfast… or so the story goes. This idea is widely believed in popular culture as well as by many nutrition scientists and government bodies and is repeated so often that many in the field consider it health dogma. Indeed, the Dietary Guidelines for Americans even recommend breakfast consumption as an important tool for weight loss. But what does the science say?
Observational studies indicate that breakfast consumption is linked to lower weight. Data from the National Weight Control Registry demonstrated that 78% of the nearly 3,000 subjects included in the analysis (adults who had lost at least 13 kg and kept the weight off for a year or more) reported eating breakfast everyday and only 4% reported never eating breakfast . Further, a recent meta-analysis of observational studies that have evaluated the relation between weight and breakfast consumption found that skipping breakfast was associated with a 55% increased odds of having overweight or obesity . These findings are likely the reason many tout breakfast consumption as an important weight loss modality, despite these studies not actually testing that outcome.
Observational studies can only describe associations, but are not appropriate to determine causation. Thus, randomized controlled trials (RCTs) have sought to test whether breakfast consumption directly impacts weight. In one of the first RCTs to evaluate the role of breakfast in weight loss, Schlundt et al. studied women with obesity who were self-reported breakfast eaters or skippers.Within each group, women were randomized to eat or skip breakfast in addition to following a 1200 kcal/day diet for 12 weeks. All groups lost at least 6 kg, but interestingly, those who were randomized to switch their breakfast condition (e.g. ate breakfast at baseline, then started skipping) lost more weight than those who maintained their breakfast habit. These results suggest that changing an eating behavior in addition to following a reduced calorie diet may accelerate weight loss. However, the results from a study by Dhurandhar et al. did not corroborate those findings. Adults with overweight and obesity were randomized to one of three conditions in which all groups received a USDA pamphlet on healthy eating practices: the control group received no other information, one group received additional instructions to consume breakfast, and the third group was instructed to not eat breakfast . After 16 weeks, there was no observed effect of treatment assignment on weight loss.Contrary to the results from the Schlundt study, baseline breakfast eating habit was not related to weight change, though this study didn't evaluate breakfast consumption in conjunction with a reduced calorie diet.Finally, in a recently published 4-week study, adults with overweight and obesity were randomized to three different breakfast conditions: water (control), frosted flakes, or oatmeal .Interestingly, skipping breakfast resulted in an average weight loss of 1.2 kg, while those randomized to either breakfast condition demonstrated no significant weight change.However, total cholesterol also increased in the control group, suggesting that skipping breakfast may result in slight weight loss, but have detrimental effects on cardiometabolic health.
Thus, the results from the few RCTs completed in adults with overweight and obesity, to date, do not support the notion that breakfast consumption should be part of a weight loss regimen. Importantly, though, the results are also not compelling to suggest that eating breakfast hinders weight loss. This field is still young and many questions remain unanswered. I look forward to more RCTs evaluating breakfast consumption (and potentially, breakfast quality) on various facets of weight and metabolic health.
1.Wyatt, H.R., et al., Long-term weight loss and breakfast in subjects in the National Weight Control Registry. Obes Res, 2002. 10(2): p. 78-82.
2.Brown, A.W., M.M. Bohan Brown, and D.B. Allison, Belief beyond the evidence: using the proposed effect of breakfast on obesity to show 2 practices that distort scientific evidence. Am J Clin Nutr, 2013. 98(5): p. 1298-308.
3.Schlundt, D.G., et al., The role of breakfast in the treatment of obesity: a randomized clinical trial. Am J Clin Nutr, 1992. 55(3): p. 645-51.
4.Dhurandhar, E.J., et al., The effectiveness of breakfast recommendations on weight loss: a randomized controlled trial. Am J Clin Nutr, 2014. 100(2): p. 507-13.
5.Geliebter, A., et al., Skipping breakfast leads to weight loss but also elevated cholesterol compared with consuming daily breakfasts of oat porridge or frosted cornflakes in overweight individuals: a randomised controlled trial. J Nutr Sci, 2014. 3: p. e56.
The term “food security” at a basic level was defined by the World Food Summit of 1996 as “when all people at all times have access to sufficient, safe, nutritious food to maintain a healthy and active life” (FAO 1996). This is obviously a key element in success and well-being of any people, though its realization will look a little bit different in America, where we do still have food insecure, compared to other parts of the world.
There are many facets to the problem: poor infrastructure and organization, poverty, limited education, social injustice and gender inequality, conflict, and lack of natural resources. Solutions also cannot generally be broadly applied because each country experiences these issues differently. Despite the successes of the Green Revolution in agriculture and food research implementation and nutrition interventions since the 1960's, around 850 million people (or about 15% of the world's population) remain malnourished. For children specifically, this jumps to 20%. The enormity of the problem can leave a person wondering what possible difference one person or one organization could make.
On May 8, I traveled to Uganda on 3-week assignment with a United States-based NGO whose mission is to serve the vulnerable in developing countries with development and relief efforts. Uganda, like the surrounding countries, is given a “low human development” score in the 2014 Human Development Report by the United Nations. In 2006, 38% of Ugandan children experienced chronic malnutrition, or stunting. Vitamin A and iron deficiency remain critical problems in population health, especially for mother and children (FAO 2010).
The broad focus of my assignment was nutrition education and recipe development for a small-holder farmer cooperative. In general, farmers are an important target for nutrition education because they are able to impact the local food supply and most farmers are women of reproductive age.
Preparing for my trip, I wasn't sure what kind of impact I would have. A semi-tropical climate allows Ugandans to grow and consume a variety of foods, and on paper I thought their diet seemed pretty adequate. But of course things on paper are always a bit different than what you find in reality.
I spent two days with each group of farmers, the first day communicating (through a translator) the basic, important concepts of nutrition and the second explaining and demonstrating foods and preparation methods that could improve the diet quality of people in their district. I shared the kind of information that we take for granted: the role of carbohydrates, protein, fat, vitamins, and minerals in our bodies and the importance of consuming a balanced diet including a variety of foods in addition to other simple but important tidbits like “don't feed tea and coffee to your children.” When it came to recipe demonstrations, I explained things that most people in the US could look up on a computer whenever they wanted, but for these women and men was not accessible.
Along the way, I began to recognize that consumption patterns, while related to economic factors, often have more to do with cultural practices and preferences and societal barriers. A visitor to Uganda immediately notices the huge amount of carbohydrate sources consumed at every meal. There are several, including Irish potatoes, (white) sweet potatoes, cassava, green banana, rice, corn and millet-based pastes, and wheat-based chapatti. Ugandans also grow a variety of beans, ground and tree nuts, vegetables, and fruits, so it is not that nutritious foods are totally absent, but are consumed in skewed proportions.
Fruit is considered child's food, and vegetables (including beans) are consumed in very small amounts. Meat, dairy, and eggs are not widely affordable, and insects and fish have an undesirable “poor food” stigma attached. Influences and perceptions of a Western diet have made white bread and other packaged foods sought-after commodities, rather than the native whole grain millet, avocadoes, mangos, and other naturally nutritious foods that Americans are ironically trending towards.
In lacking a strong education system and broad computer access, Ugandan people live in an information desert. Despite the agricultural potential for variety, many dishes are made and consumed the same way day after day with the same ingredients because knowledge on nutrition and food preparation is lacking. There are countries with enough conflict and natural resource struggles that educating on the benefits of vegetable and dairy/animal protein consumption might be a moot point, but in Uganda these things are more achievable. Timing seems critical: these farmers were at a point where they requested this training, and that makes the potential impact far greater.
Easily-modified agricultural factors can have broad influence on the diet. For example, simple introduction of orange-fleshed, rather than white-fleshed, sweet potatoes can vastly improve vitamin A intake. Increasing use of fertilizers or crop rotation practices can ensure that minerals which foods like peanuts should theoretically contain are actually present.
Gender-related issues can also impact diet quality. Women are responsible for feeding themselves and their children, but the money, even money they earned, is not always in their hands. Men may have a nice meal at a restaurant while women eat cassava and potatoes at home. In addition, the common practice of multiple wives and the perception of children as a status symbol often make families quite large.
Overall, while economic, agricultural, and societal factors do play a role in food security, in countries such as Uganda I think nutrition education has strong potential to directly provide needed knowledge and indirectly change practices and prejudices that impede diet quality. My personal experience fully supports UNICEF recommendations for future nutrition education programs, including starting young, investing in women and girls, and collaborating across ministries to support integrated approaches to improving the diet (Unicef 2014). These integrated approaches address other strong nutrition influencers such as food safety and hygiene and health and disease, in addition to agricultural production.
FAO. 1996. “Declaration on World Food Security.” World Food Summit, Rome: FAO.
FAO. 2010. “Uganda.” United Nations. http://www.fao.org/ag/AGN/nutrition/uga_en.stm
Unicef. 2014. “Multi-Sectoral Approaches to Nutrition: The Case for Investment by Educational Programmes.” http://www.unicef.org/eapro/Brief_Education_Nutrition.pdf
For nutrition professionals, deciphering the Nutrition Facts labels on food packages may be second nature. However, for the general public it is often difficult to understand and interpret this information. The FDA took this into consideration when proposing new requirements for Nutrition Facts labels in 2014 (1). Two main changes were proposed: new information on labels as well as design changes and new serving and package size requirements (2). The appearance of the label will be quite different if they are accepted.
This is of course to be the biggest change since 1993. The only alteration in the past 20 years has been the requirement of the amount of trans fat to the label in 2006 (1). This month the FDA proposed two more changes to the label. The one getting the most attention is the percent daily value of added sugars.
The most notable changes issued in March 2014 were (1):
• increased font size of calories
• changing of serving size requirements
• placement and update of percent daily value
• including added sugars
• removing calories from fat
• including the gram amount of micronutrients
• including vitamin d and potassium
• making vitamin C and vitamin A voluntary
As of this July 2015, two new changes were proposed (1):
• require the percent daily value of added sugars
• change the footnote to help consumers understand daily values
What are considered added sugars?
Simply stated added sugars are not naturally occurring and are added to the product. ChooseMyPlate says they are sugars that are added when processed or prepared. USDA lists some common sources of added sugars seen on ingredient lists including corn syrup, honey, fructose and lactose. However, for many manufactures this can be quite difficult to quantify because fructose and lactose are naturally occurring in fruits and milk. Yet, when they are added during processing they are now considered an “added sugar”. The current requirements from the FDA states in The Code of Federal Regulations Title 21 (101.60 c) that manufactures can use the claim “No added sugars” if “no sugar or sugar-containing ingredient is added during processing” (3).
Why does the FDA want percent daily value of added sugars?
Currently, there is no percent daily value of sugars because the FDA recommends that consumers limit their sugar intake to as low as possible. Things changed this month when the FDA argued that the percent daily value helps consumers understand how much is too much added sugars. Added sugars provide no nutrient value, increase caloric intake and replace nutrient dense foods. Susan Mayne, director of the FDA's Center for Food Safety and Applied Nutrition, argued this change will help consumers reduce their intake of added sugars (4).
How much is too much of added sugars?
FDA recommends that daily intake of added sugars should not exceed 10% of total calories (1). If you are eating a 2,000 calorie diet you can easily exceed this 10% mark by consuming one 20 fl oz Minute Maid Lemonade.
How are food manufacturers reacting?
Food companies argue that including added sugars and a percent daily value could be misleading because the body utilizes added sugars the same as natural sugars and question the amount and quality of scientific evidence the FDA used to support their new proposal. Manufacturers claim that nutrition information seldom alters consumer's food intake, so these changes would be more costly than they would be beneficial (5).
When can the public see these new changes?
The two new proposed changes will go through a comment period before they are accepted.
By: R. Alex Coots
Academia is changing.
Today's universities increasingly rely on adjunct faculty to teach courses and reserve the coveted full-time academic position for the science superstars. This phenomenon, coupled with decreasing paylines from funding agencies, makes a science career especially challenging to pursue. And that's not even considering the project difficulties!
The problem has become so pressing that even the NIH has realized it. New initiatives, such as the BEST Innovation Award, aim to ensure that graduate students and post-docs have increased opportunities to expand their skill sets for a future outside of academia.
Policy is one of the many areas that nutrition experts can serve. The current Director of the Office of Dietary Supplements (ODS), Dr. Paul Coates, successfully made the transition from bench research as a geneticist to a career in science policy. He spoke with me about his career and transition to ODS.
What motivated your interest into policy?
I was curious. For all these years, I had been funded to do research by the NIH and other organizations, but what I concentrated most on was my own research. I was pretty naïve when I came to the NIH, not knowing what life was like for people who worked on the government side. There were plenty of them like me, PhD's in one setting or another, who had come to the NIH to work as extramural program directors.
What are the important skills or knowledge that someone should have when moving into policy?
One of the things I understood was the importance of making connections. My first job at the NIH was focusing on diabetes research efforts. I learned how to work with other people within an institute, and then gradually in other institutes and beyond to achieve common goals. I think the art of science policy is knowing who else works in this field that you can benefit from, and flip it around and ask “How can I help other people benefit from working together with them?” Recognize the talent that's out there in other organizations.
What advice would you give to students?
You need to pay your dues as a scientist first. You need to understand the scientific method. You don't have to spend an eternity in science, but you must have spent some time doing it. Author publications and write grants. My observation is that the people best prepared for this kind of experience “get it” about what a scientist does. They must be prepared to critically analyze data and know what to look for in the literature to inform policy.
What types of projects do the AAAS and Milner fellows work on?
The AAAS Science and Technology Policy Fellowship is beautifully designed to encourage people at different levels of experience in science to work closely with federal agencies to learn about the science-to-policy transition. In ODS, we're recent partners in that program. Fellows are engaged in projects that my office works on. We have a very active role in translating science into policy, but also in identifying research needs.
The Milner fellowship has a different side to it. Jointly funded by ODS and the Beltsville Human Nutrition Research Center, the Milner fellowship brings in one or two people per year for a two-year stint that will allow them to conduct research in one of the labs at Beltsville. At the same time, they participate at ODS in work on science policy.
How do you see ODS changing in the future?
ODS is getting a little older. A fairly urgent challenge is identifying people who can come up behind us and continue to identify opportunities for research—particularly those that have public health implications— and be committed to help tackle them.
John E. Courtney, PhD
As a society, ASN highlights the very best scientific research that promotes healthy people and communities; we recognize that nutrition research is conducted within and across the public, private and government sectors of our society. ASN members understand that the nutrition challenges facing the world are multi-faceted and require research-based solutions. The Society also understands that public confidence in scientific research and integrity is essential to translate scientific evidence into improved dietary practices by consumers.
ASN's professional activities allow members to come together and share information and research findings that accelerates discoveries that allow us to better understand the connections among diets and health. As a broad member-based organization, we are transparent about the fact that industry, government, trade groups and other scientific organizations contribute funding to help our society support the research enterprise for all of our members. ASN is committed to openness, objective science, and disclosure of potential conflicts. The Society's Conflict of Interest attestation and “guiding principles for working with external groups and addressing COI” can be found on our website. All of the Editors for ASN's three journals have publicly-available conflict of interest statements, which is not a required process and is an example of our commitment to transparency.
ASN promotes rigorous research that highlights the very best dietary practices, policies and guidance. Because issues of nutrition impact virtually every aspect of the food supply chain, involvement of all informed stakeholders in the scientific enterprise is essential. Furthermore, in today's extremely competitive research environment, industry support helps progress research that might otherwise be impossible due to limited federal funding. ASN, like all scientific societies, remains vigilant in safeguarding the integrity of the scientific process from the biases and influences that can be associated with research funding from all sources. Without scientific integrity, there can be no public trust.
ASN does not have small goals, and therefore we cannot work in a vacuum. We believe that scientists in academia, government, and industry can partner to solve the world's nutrition challenges. Our members work with moms and dads, children, the elderly, the sick, the under- and over- nourished, foundations, companies, governments, and media. We look forward to continuing to work with all stakeholders who are passionate about nutrition and committed to the highest ethical standards for research that advances the public health to achieve a healthier world.
ASN welcomes all to the table to learn from one other and to make progress on continuing to solve today's complex nutrition challenges. These challenges include improving mechanisms and processes to fund, conduct and review nutrition research that improves global health.
First released in 1980, the Dietary Guidelines for Americans are updated and jointly published by the U.S. Department of Agriculture (USDA) and the U.S. Department of Health and Human Services (HHS) every 5 years. These guidelines provide recommendations on nutrition and physical activity for Americans aged 2 and older, and are the driving force behind Federal nutrition policies, nutrition education and food procurement programs. As such, these guidelines are used by both the public and industry, and by a wide variety of audiences including educators, health professionals and government agencies.
Earlier the 2015 Dietary Guidelines Advisory Committee (DGAC) released a Scientific Report based on the latest evidence, which will shape the finalized guidelines later this year. The committee's work was influenced by two fundamental connections between nutrition and lifestyle-related health issues facing the U.S population:
1) Chronic diseases, overweight and obesity: about half of all American adults (~117 million) have one or more preventable chronic diseases such as type 2 diabetes, cardiovascular diseases, hypertension, and diet related cancers, and about two-thirds of adults and one-third of children are overweight or obese due to poor dietary habits and physical inactivity.
2) Food environment and settings: diet and lifestyle behaviors are strongly influenced by personal, social, organizational, and environmental context and systems. As such, the DGAC developed their recommendations based on a conceptual model of socio-ecological framework to provide recommendations at the individual, social, organizational, and environmental level.
What does the DGAC's report say about the latest research on diet and lifestyle-related health outcomes?
The DGAC found that the current average American diet is low in vegetables, fruits, and whole grains and too high in refined grains, added sugars, saturated fat, and sodium. Furthermore, inadequate consumption of vitamin D, calcium, fiber, and potassium were categorized as nutrients of public health concern for the majority of the U.S population. Lifestyle-related health problems in the U.S. have persisted for more than 2 decades and the DGAC's report calls for urgent preventative actions at the national, state, and local community levels. The DGAC recommended a shift in focus to a more environmentally friendly, sustainable plant-based diet that focuses on whole foods rather than specific nutrients. The overall body of evidence examined by the committee is summarized below:
“A diet higher in plant-based foods, such as vegetables, fruits, whole grains, legumes, nuts, and seeds, and lower in calories and animal based foods is more health promoting and is associated with less environmental impact than is the current U.S. diet.”
This is not to say that any food groups need to be eliminated completely to improve health and sustainability outcomes. In fact, the DGAC recommended three dietary patterns to provide options that can be adopted by the U.S. population and are also aligned with lower environmental impacts. These dietary patterns include the Healthy U.S. style Pattern, the Healthy Mediterranean style Pattern, and the Healthy Vegetarian Pattern. Furthermore, the 2015 DGAC left out cholesterol restrictions where previously, the 2010 DGAs recommended that cholesterol intake be limited to no more than 300 mg/day. The up-to-date evidence on cholesterol showed no substantial relationship between dietary consumption of cholesterol and blood cholesterol. Thus, the 2015 DGAC concluded, “Cholesterol is not a nutrient of concern for overconsumption.”
The message is clear—the 2015 DGAC recommends the U.S population consume dietary patterns that are rich in vegetables, fruits, whole grains, seafood, legumes, and nuts; moderate in low- and non-fat dairy products and alcohol; lower in red and processed meat; and low in saturated fat (less than 10% of total calories consumed per day), added sugars (maximum of 10% of total calories consumed per day), and sodium (2,300 mg per day or age-appropriate Dietary Reference Intake amount). Whether the USDA and the HHS will choose to adopt or ignore these recommendations put forth by the 2015 DGAC remains uncertain at this point. Meanwhile, dozens of health and environmental groups support the committee's recommendations regarding sustainability, as viewed in the open letter found at My Plate My Planet, Food for a Sustainable Nation.
The advisory recommendations put forth by the 2015 DGAC are also closely aligned with recent research highlighting the urgency of shifting global diets, where healthy dietary patterns (i.e. Vegetarian, Pescetarian, and Mediterranean diets) are found to be associated with more favorable health as well as environmental outcomes. Thus, the available data strongly suggest that diets that are higher in plant-based foods will not only improve personal and public health, but also boost our planet's health via “weight” reduction in greenhouse gases mainly due to reduction in livestock production.