How dietary factors influence disease risk

At a Glance Researchers found that eating too much or too little of certain foods and nutrients can raise the risk of dying of heart disease, stroke, and type 2 diabetes.

These results suggest ways to change eating habits that may help improve health.

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Having too much sugar, salt, or fat in your diet can raise your risk for certain diseases. Healthy eating can lower your risk for heart disease, stroke, diabetes, and other health conditions. A healthy eating plan emphasizes vegetables, fruits, whole grains, and fat-free or low-fat dairy products; includes lean meats, poultry, fish, beans, eggs, and nuts; and limits saturated and trans fats, sodium, and added sugars.

The major cardiometabolic diseases—heart disease, stroke, and type 2 diabetes—pose substantial health and economic burdens on society. To better understand how different dietary components affect the risk of dying from these diseases, a research team led by Dr. Dariush Mozaffarian of Tufts University analyzed data from CDC’s National Health and Nutrition Examination Survey (NHANES) and national disease-specific mortality data. The study was supported in part by NIH’s National Heart, Lung, and Blood Institute (NHLBI). Results appeared on March 7, 2017, in the Journal of the American Medical Association.

The researchers investigated the relationships of 10 different foods and nutrients with deaths related to heart disease, stroke, and type 2 diabetes. They also compared data on participants’ age, sex, ethnicity, and education. They found that nearly half of all the deaths in the United States in 2012 that were caused by cardiometabolic diseases were associated with suboptimal eating habits. Of 702,308 adult deaths due to heart disease, stroke, and type 2 diabetes, 318,656 (45%) were associated with inadequate consumption of certain foods and nutrients widely considered vital for healthy living, and overconsumption of other foods that are not.

The highest percentage of cardiometabolic disease-related death (9.5%) was related to excess consumption of sodium. Not eating enough nuts and seeds (8.5%), seafood omega-3 fats (7.8%), vegetables (7.6%), fruits (7.5%), whole grains (5.9%), or polyunsaturated fats (2.3%) also increased risk of death compared with people who had an optimal intake of these foods/nutrients. Eating too much processed meat (8.2%), sugar-sweetened beverages (7.4%), and unprocessed red meat (0.4%) also raised the risk of heart disease, stroke, and type 2 diabetes-related deaths.

The study showed that the proportion of deaths associated with suboptimal diet varied across demographic groups. For instance, the proportion was higher among men than women; among blacks and Hispanics compared to whites; and among those with lower education levels.

“This study establishes the number of cardiometabolic deaths that can be linked to Americans’ eating habits, and the number is large,” explains Dr. David Goff, director of the NHLBI Division of Cardiovascular Sciences. “Second, it shows how recent reductions in those deaths relate to improvements in diet, and this relationship is strong. There is much work to be done in preventing heart disease, but we also know that better dietary habits can improve our health quickly, and we can act on that knowledge by making and building on small changes that add up over time.”

These findings are based on averages across the population and aren’t specific to any one person’s individual risk. Many other factors contribute to personal disease risk, including genetic factors and levels of physical activity. Individuals should consult with a health care professional about their particular dietary needs.

—Tianna Hicklin, Ph.D.