Optimal Nutrition for Personal, Population and Planetary Health
Dr. Frank B. Hu, M.D., PhD | Chair of Department of Nutrition and Fredrick J. Stare Professor of Nutrition and Epidemiology at Harvard T.H. Chan School of Public Health
Watch This Presentation:
Dr. Frank B. Hu, professor of nutrition and epidemiology at Harvard University, discussed the effects of an unhealthy diet on the body and how prioritizing a plant-based diet can lower the risks of chronic diseases in his presentation entitled "Optimal Nutrition for Personal, Population, and Planetary Health."
The planet is changing due to human activity, and there is no doubt that we are making it harder to meet the demands of the growing population. Obesity, undernutrition and climate change form the triple threat that currently faces the global population. With 88% of countries facing a serious burden of at least two forms of malnutrition and the projection of reaching 10 billion people on Earth by 2050, humanity needs to make serious changes in dieting.
The EAT-Lancet commission recognizes the challenge of feeding the growing population a diet that is healthy and sustainable, but the standard response to simply grow more food will not suffice. Their approach outlines defining a healthy reference diet and planetary boundaries, applying a global food systems modeling framework, and outlining strategies to achieve these necessary changes.
But how do we know if we're eating a healthy diet? Unfortunately, "there's no app for that," joked Dr. Hu. Researchers have developed an index to measure the quality of diets, including whole grains, fruits and vegetables, red meats and more. The perfect score is 100, yet most people only score around 50. When country averages are displayed on a map, Mediterranean and Caribbean countries tend to have a higher diet quality, while the United States is very below average. If the global population improves in healthy eating, it is estimated that 11.6 million premature deaths could be prevented annually.
Conflicting research findings spark debates over what is and what is not considered "healthy." One of the recurring debates Dr. Hu questioned is whether butter is healthy or not. There is nothing that can indicate any one simple answer for this, one must look at what it is compared to. By replacing saturated fat with unsaturated fats such as olive oil, avocado and nuts, the risk of heart disease is significantly lower. However, when replacing butter with more carbohydrates and refined starch like drinking soda or eating more white bread, the risk of heart disease does not change. Increased consumption of processed red meat also increases the risk of type 2 diabetes and mortality. By replacing red meat with other protein-rich foods such as nuts, legumes, low fat dairy, poultry or fish, we can reduce the morality risk 7 – 19%. If everyone reduces their intake, 9.3% of male and 7.6% of female premature deaths can be prevented annually. While animal protein consumption increases the risk of cardiac disease, more plant-based protein consumption results in lower risk of heart disease and diabetes.
However, it is noteworthy that not all plant-based diets are healthy. People who consume plant-based diets with refined carbohydrates and sodium may have risks that are actually worse than those from consuming animal products. Increasing refined grains and sugar sweetened beverages is associated with increased weight gain, while limiting the diet to healthy foods like fruits, whole grains, vegetables, nuts and yogurt is associated with less weight gain.
Recent studies have looked toward personalizing nutrition to determine the best diet for people individually. While an algorithm has proved more successful at controlling blood sugar than a dietician, it is unknown whether these results can be generalized and feasible in clinical practice. The biggest factor to blame in the fight for health is not genes, but the food environment. The cheapest and most accessible foods are fast food and unhealthy snacks that are loaded with sugar, sodium and unhealthy fats.
What are our options for a healthy future? We must create healthy food environments, restrict fast food marketing, implement public education campaigns and lobby for zoning laws to limit the number of fast food restaurants in an area. The 2015 Dietary Guidelines Advisory Committee Report details that there is no need to go completely vegetarian, but to improve public health and reduce our environmental impact we need to increase fruit, vegetables, whole grains, nuts and legumes in our diets and reduce animal based foods. The EAT-Lancet commission finds that feeding 10 billion people a healthy diet is feasible, as long as current diets change to planetary healthy ones.
Dr. Hu argued that there is a bright future ahead. When changing the population's diet, we not only help the planet but we help ourselves. Diets higher in plant-based foods and lower in animal-based foods are key, as well as changing the way we see affordability and nutrient-rich food. The optimal nutrition is a Venn diagram of public health nutrition, precision nutrition for personal health and sustainable nutrition for the planet. When all of these are integrated, the health of future generations looks promising.
About the Speaker
Dr. Frank Hu is Chair of Department of Nutrition and Fredrick J. Stare Professor of Nutrition and Epidemiology at Harvard T.H. Chan School of Public Health and Professor of Medicine, Harvard Medical School and Brigham and Women’s Hospital. He serves as Co-Director of the Program in Obesity Epidemiology and Prevention at Harvard and Director of Boston Nutrition and Obesity Research Center (BNORC) Epidemiology and Genetics Core. Dr. Hu received his M.D. from Tongji Medical College in China and a Ph.D. in Epidemiology from University of Illinois at Chicago. Dr. Hu is the recipient of the Kelly West Award for Outstanding Achievement in Epidemiology by the American Diabetes Association in 2010. He was named the American Heart Association’s Ancel Keys Memorial Lecturer in 2018. He has served on the Institute of Medicine (IOM) Committee on Preventing the Global Epidemic of Cardiovascular Disease, the AHA/ACC Obesity Guideline Expert Panel and the 2015 Dietary Guidelines Advisory Committee, USDA/HHS. He currently serves on the editorial boards of Lancet Diabetes & Endocrinology, Diabetes Care, and Clinical Chemistry. Dr. Hu is a member of the National Academy of Medicine.