Margaret McCartney: Promising miracle diet fixes isn’t fair on anyone

In the world of nutrition, “low carb and high fat” diets are a growing trend. Big claims are made, including from doctors, that these can “save your life,” “reverse type 2 diabetes,” and, of course, help you lose weight.1234 So, should GPs start recommending low carbohydrate diets to people who want to lose weight or who have type 2 diabetes?

Criticism of the status quo is reasonable. By its nature, diet research contains many uncertainties, with few long term randomised controlled trials. But doctors, researchers, and guideline committees can surely aspire to do better.

Many in the low carb lobby have been highly critical of current government dietary guidance. Some legitimately criticise conflicting or weak evidence underpinning …