Improving dietary quality around the world could prevent more than 11 million premature deaths—roughly 24% of the total deaths in 2017—according to a new study led by Harvard T.H. Chan School of Public Health.
To estimate diet-related health outcomes for millions of people around the world, researchers used the Alternative Healthy Eating Index (AHEI), which is used to score a person’s diet based on the quality of the food they eat and is a strong predictor of major chronic diseases. The AHEI rates dietary quality on a score of 0 to 110, with higher scores indicating healthier diets.
The study, published online May 2, 2019 in The Journal of Nutrition, found that the average global AHEI score for men in 2017 was 49.5 and 50.5 for women. From 1990 to 2017, the average global AHEI score increased modestly from 45.4 to 50.
The study also found that diet quality varied substantially across the world. Coastal Mediterranean nations, the Caribbean, and Eastern Asia, except for China and Mongolia, had a higher AHEI score. Central Asia, the South Pacific, and Eastern and Northern Europe had a lower score.
The authors estimated that improving the current global diet could prevent 1.6 million cancer deaths, 3.9 million coronary artery disease deaths, 1 million stroke deaths, 1.7 million respiratory disease deaths, 0.4 million neurodegenerative disease deaths, 0.5 million kidney disease deaths, 0.6 million diabetes deaths, and 1.2 million digestive disease deaths.
Harvard Chan co-authors of the study included Dong Wang, Yanping Li, Meir Stampfer, Frank Hu, and Walter Willett.