Here's How Many Heart Disease & Diabetes Deaths Are Linked to Food

Nearly half of all deaths from heart disease, stroke and type 2 diabetes may be due to diet, a new study finds.

In 2012, 45 percent of deaths from "cardiometabolic disease" — which includes heart disease, stroke and type 2 diabetes — were attributable to the foods people ate, according to the study.

This conclusion came from a model that the researchers developed that incorporated data from several sources: The National Health and Nutrition Examination Surveys, which are annual government surveys that provide information on people's dietary intakes; the National Center for Health Statistics, for data on how many people died of certain diseases in a year; and findings from studies and clinical trials linking diet and disease. [7 Foods Your Heart Will Hate]

The researchers found that, in 2012, just over 700,000 people died from a cardiometabolic disease. Of these deaths, nearly 320,000 — or about 45 percent — could be linked to people's diets, according to the study, published today (March 7) in the journal JAMA.

The estimated number of deaths that were linked to not getting enough of certain healthier foods and nutrients was as least as substantial as the number of deaths that were linked to eating too much of certain unhealthy foods, according to the researchers, who were led by Renata Micha, a research assistant professor of nutrition and epidemiology at Tufts University in Boston.

In other words, Americans need to do both: Eat more healthy foods, and less unhealthy food.

The researchers focused their analysis on 10 food groups and nutrients: fruits, vegetables, nuts and seeds, whole grains, unprocessed red meat, processed meat, sugar-sweetened beverages, polyunsaturated fats, omega-3 fats from seafood, and salt, according to the study.

For each food or nutrient, the researchers identified an "optimal intake" amount. When people ate more or less than this optimal amount, the intake was considered suboptimal.

Overall, the greatest number of deaths were linked to suboptimal sodium intake; in other words, eating too much salt. The researchers' model found that about 66,500 cardiometabolic deaths in 2012 were linked to high sodium intake.

Not eating enough nuts and seeds was the dietary factor linked to the second highest number of deaths (59,000), followed by too much processed meat (58,000 deaths), too little omega-3 fats from seafood (55,000 deaths), too few vegetables (53,000 deaths), too few fruits (52,500 deaths) and too many sugar-sweetened beverages (52,000 deaths), according to the study.

When the researchers looked at specific demographic groups within the study, they found that more deaths in men were linked to dietary factors than in women. In addition, a greater number of deaths in younger people were linked to dietary factors, compared with older people. There was also a greater number of deaths linked to diet among African-Americans and Hispanics when compared with non-Hispanic whites. 

The researchers also calculated the percentage of deaths in 2002 that were linked with dietary factors, and found that deaths linked to certain dietary factors — such as too many sugar-sweetened beverages, not enough nuts and seeds and not enough polyunsaturated fats — decreased between 2002 and 2012. The number of deaths attributed to factors such as sodium and unprocessed red meats, however, increased over the same time.

Notes of caution

The findings have the potential to help guide public policy planning to prevent early deaths and reduce health disparities, according to an editorial that was published alongside the study in the same journal. The editorial was written by Noel Mueller, an assistant professor of epidemiology at the Johns Hopkins Bloomberg School of Public Health, and Dr. Lawrence Appel, a professor of medicine at the same institution. [5 Diets That Fight Disease]

However, there are several limitations to consider, Mueller and Appel wrote. For example, the calculations that the researchers made in the new study assume that there is a cause-and-effect relationship between dietary factors and death, they wrote. However, the studies used in the model were observational studies, which don't prove cause-and-effect, they wrote.

In addition, Mueller and Appel noted that there may be other dietary factors beyond the 10 included that could play a role, such as saturated fat and added sugar. It's also possible that certain dietary factors are linked, such as sodium and processed meats, they wrote.

Despite the limitations, the study is "quite relevant to public health nutrition policy," Mueller and Appel wrote. As the study authors suggested, "policies that affect diet quality, not just quantity, are needed," they wrote.

Originally published on Live Science.