A new analysis has shown that 11 million deaths worldwide was linked to poor diet. An international group of hundreds of researchers called the Global Burden of Disease 2017 Diet Collaborators funded by the Bill and Melinda Gates Foundation found that eating diets high in salt and low in fruit, vegetables wholegrains, and nuts and seeds was linked to more than half of the deaths.
National food frequency questionnaires as well as food sales data were used to estimate consumption of 15 different aspects of diet including vegetables and red or processed meat for each country. They then compared this to data from observational studies to assess the impact that these diets have on cardiovascular diseases, cancer, type 2 diabetes, and the risk of death.
While these results do emphasise the importance of healthy eating, it should be noted that there are some limitations to this kind of study. The main one is that it was based on observational data, proving correlation rather than causation. It cannot be used to prove definitively that poor diet was what caused the increase in illness and death. That being said there are clear links between each dietary component and disease. Cutting down on salt as well as red and processed meat and saturated fats is known to have health benefits. So is increasing consumption of fruit and vegetables along with wholegrain, nuts, and seeds.