Dietary risk factors—such as consuming too much sodium or not enough whole grains and fruits—were responsible for 11 million deaths globally in 2017, according to a new analysis in The Lancet.
These factors also cost the population about 255 million disability-adjusted life-years (DALYs), reported Ashkan Afshin, MD, and colleagues, who studied dietary data as part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2017. The researchers collected and analyzed intake for 15 foods and nutrients among adults 25 and older across 195 countries, using the geographically representative data to quantify the impact of diet on non-communicable disease (NCD) mortality. All data came from 1990 through 2017.
Overall, Afshin et al. found high intake of sodium and low intake of whole grains were the dietary risk factors associated with the most premature deaths—about 3 million for each factor in 2017. Low intake of fruits was next at 2 million deaths.
The data indicated that people consistently underconsume healthy foods and overeat unhealthy foods. For instance, the observed intake of nuts and seeds was only 12% of the optimal level, while the mean consumption of milk and whole grains was just 16% and 23% of optimal levels, respectively. On the other hand, global consumption of processed meat was 90% higher than the optimal level and red meat consumption outpaced the ideal rate by 18%.
“This study provides a comprehensive picture of the potential impact of suboptimal diet on NCD mortality and morbidity, highlighting the need for improving diet across nations,” Afshin and co-authors wrote. “Our findings will inform implementation of evidence-based dietary interventions and provide a platform for evaluation of their impact on human health annually.”
Cardiovascular disease was the leading cause of mortality in 10 million of the 11 million diet-related deaths, according to the authors. Cancer dealt the knockout blow in an estimated 913,000 cases, while type 2 diabetes was next with 339,000 diet-related deaths attributed to it.
“We found that improvement of diet could potentially prevent one in every five deaths globally,” the researchers wrote. “Our findings show that, unlike many other risk factors, dietary risks affected people regardless of age, sex, and sociodemographic development of their place of residence. Although the impact of individual dietary factors varied across countries, non-optimal intake of three dietary factors (whole grains, fruits, and sodium) accounted for more than 50% of deaths and 66% of DALYs attributable to diet.”
Importantly, the authors noted, some of the most impactful factors have gone underrecognized in dietary policies—suggesting more effective interventions could be attempted if priorities are reshuffled.
“Although sodium, sugar, and fat have been the main focus of diet policy debate in the past two decades, our assessment shows that the leading dietary risk factors for mortality are diets high in sodium, low in whole grains, low in fruit, low in nuts and seeds, low in vegetables, and low in omega-3 fatty acids; each accounting for more than 2% of global deaths,” Afshin et al. wrote.
“This finding suggests that dietary policies focusing on promoting the intake of components of diet for which current intake is less than the optimal level might have a greater effect than policies only targeting sugar and fat, highlighting the need for comprehensive food system interventions to promote the production, distribution, and consumption of these foods across nations.”