Suboptimal diet is responsible for more deaths globally than any other risks, even tobacco smoking, according to a major new review* published today in The Lancet. The experts who led the Global Burden of Disease (GBD) study said their findings highlight the urgent need to improve human diet at global, regional, and national level – and that we should focus more on increasing intake of beneficial foods, rather than on simply restricting sugar and fat.
The team, funded by the Bill & Melinda Gates Foundation, systematically collected geographically representative dietary data from multiple sources; characterised the population distribution of intake for 15 foods and nutrients among adults aged 25 years or older across 195 countries; estimated the effect of each individual dietary factor on non-communicable disease (NCD) mortality; and quantified the overall impact of poor dietary habits on NCD mortality. They also evaluated the relationship between diet and socioeconomic development, and assessed the trends in disease burden of diet over time.
They reported that in 2017, 11 million deaths and 255 million disability-adjusted life-years (DALYs) were attributable to dietary risk factors. High intake of sodium (three million deaths and 70 million DALYs), low intake of whole grains (three million deaths and 82 million DALYs), and low intake of fruits (two million deaths and 65 million DALYs) were the leading dietary risk factors for deaths and DALYs globally and in many countries. Out of all 195 countries, the proportion of diet-related deaths was highest in Uzbekistan, and lowest in Israel; the UK ranked 23rd, and the US 43rd.
The researchers noted that because dietary data were from mixed sources and were not available for all countries, this increased the statistical uncertainty of their estimates.
However, they commented: “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.
“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 a comprehensive food system interventions to promote the production, distribution, and consumption of these foods across nations.”
The authors of a linked comment** pointed out that these findings reinforce those of the EAT–Lancet Commission on optimising diets for sustainable food systems, achievable through predominantly plant-based diets. They said: “Limitations notwithstanding, the current GBD findings provide evidence to shift the focus, as the authors argue, from an emphasis on dietary restriction to promoting healthy food components in a global context. This evidence largely endorses a case for moving from nutrient-based to food-based guidelines.”
*GBD 2017 Diet Collaborators. Health effects of dietary risks in 195 countries, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017. The Lancet; Published online April 03, 2019. DOI:10.1016/S0140-6736(19)30041-8.
**Forouhi NG, Unwin N. Global diet and health: old questions, fresh evidence, and new horizons. The Lancet: Published online April 03, 2019. DOI:10.1016/S0140-6736(19)30500-8.