- One of the most important challenges in the field of nutrition has been published in The Lancet. It was a letter challenging the reliability of The Lancet flagship project "The Global Burden of Disease" (GBD).
- The GBD project started in 1990 and has been revised five times since. The project attempts to quantify the health effects of more than 100 diseases and harms, by age, sex and region. It estimates the ill health and deaths that could arise from different disease burdens from pollution to consumption of sugary drinks.
- The letter focused on the dietary assumptions in the most recent GBD report (2019). Substantial changes occurred between the 2017 and 2019 reports and the impact was that deaths attributed to diets high in red meat (not even processed meat) increased 36-fold.
- The key challenges made in the letter were:
1) Was this 36-fold increase reliable?
2) GBD 2019 assumed that any red meat or processed meat intake whatsoever (even one gram a day) was harmful. This in effect declared meat as a toxin. Why? What’s the evidence for this?
3) Standard procedures required by The Lancet were not followed and information was missing. Where is this?
4) Were the lost benefits of meat considered? Given that malnutrition, iron deficiency, vitamin A deficiency and zinc deficiency were recognised as key causes of disease, did the authors balance their view that no red meat should be consumed with the nutrients that this would remove from global diets?
- The authors were given the opportunity to respond to the letter but have not done so. Was GBD 2019 indefensible?