A study released earlier this year reveals that some 45% of all deaths in the U.S. in 2012 were due to “cardiometabolic disease,” or CMD – all because of the average diet. CMD encompasses heart disease, stroke, and type 2 diabetes. 
Researchers say that the largest number of diet-related CMD deaths are due to high consumption of sodium, processed meats, and sugar-sweetened drinks, and low intake of nuts and seeds, seafood omega-3 fats, and fruits and vegetables.
Says first author Renata Micha, R.D., Ph.D., assistant research professor, Tufts Friedman School of Nutrition Science & Policy in Boston, Massachusetts:
“These results should help identify priorities, guide public health planning, and inform strategies to alter dietary habits and improve health.
Increased intakes of specific minimally processed foods, such as fruits, vegetables, nuts, whole grains, fish, vegetable oils, and decreased intakes of salt, processed meats and sugar-sweetened beverages appear to be key relevant priorities for dietary and policy recommendations. Future studies should evaluate the potential effects of specific interventions to address the diet-related cardiometabolic mortality and reduce disparities.” 
Published on 7 March 2017 in JAMA, the study found that more men than women die from diet-related causes. The researchers say that, generally speaking, the findings are consistent with the fact that men tend to have unhealthier eating habits. Additionally, there were a greater number of diet-related deaths among African-Americans and Hispanics compared with non-Hispanic whites. , 
According to Micha, the estimated number of deaths that were linked to not getting enough of the healthy foods listed was at least as substantial as the number of deaths associated with eating too much of the unhealthy foods listed.
Researchers report that the highest number of deaths was linked to high sodium intake; about 66,500 CMD deaths in 2012 were linked to eating too much salt, followed by (in order):
- Not eating enough nuts and seeds (59,000 deaths)
- Eating too much processed meats (58,000 deaths)
- Eating too little seafood omega-3s (55,000 deaths)
- Not eating enough vegetables (53,000 deaths)
- Not eating enough fruits (52,500 deaths)
- Drinking too many sugar-sweetened beverages (52,000 deaths) 
The study did have its limitations. For instance, the studies the researchers used were observational, which don’t prove cause-and-effect. In addition, other dietary factors may have been at play, such as saturated fat and added sugar. And some dietary factors are potentially linked, like sodium and processed meats.
On a positive note, the researchers say that from 2002 to 2012, there were fewer diet-related CMD deaths due to insufficient polyunsaturated fats, nuts and seeds, and to excess sugary drinks. 
 Live Science