Live longer and be less gassy

By how much would a simple, healthier diet reduce your risk of dying compared to a vegetarian and a vegan diet? A new study tried to answer this question by comparing these three diets across the world.

It looked at current data and trends on diet, health, disease and greenhouse gas emissions and modelled scenarios for the year 2050 with different diets - a generally healthier diet based on current guidelines, eating fewer animal products and more plants; a vegetarian diet and a vegan diet. All were based on predicted population growth, allowing more than enough calories per person to feed everyone.

The diseases in the study included coronary heart disease, stroke, type 2 diabetes and cancer, which accounted for about for about 40 per cent of deaths globally in 2010.

Compared with the reference scenario (current situation), the study projected that the general healthier diet would result in 5.1 million avoided deaths per year, the vegetarian diet would spare 7.3 million deaths and the vegan one even more, at 8.1 million.

By 2050, these diets would reduce the number of deaths every year from heart disease, stroke, cancer, and type 2 diabetes in 2050 by 12 per cent (healthier diet), 17 per cent (vegetarian diet) and 19 per cent (vegan diet) and the overall number of deaths from all causes by 6 per cent (healthier diet), 9 per cent (vegetarian diet) and 10 per cent (vegan diet).

Each of the diets would also have an impact on global warming. If things carry on as they are, greenhouse gas emissions associated with food will increase by 51 per cent (from 7.6 giga tonnes (Gt) in 2005/2007 to 11.4 Gt in 2050) by 2050. For the three diets the figures would be – healthier diet, an increase of 8.1 Gt. Both the vegetarian and vegan diets would reduce emissions, taking us back to emissions as low as they were in the 1950s! If the world adopted a vegetarian diet, emissions in 2050 would be 4.2 Gt and if everyone went vegan, it would be as low as 3.4 Gt.

Springmann et al., 2016. Analysis and valuation of the health and climate change cobenefits of dietary change. Proceedings of the National Academy of Sciences USA. 113 (15) 4146-4151.