Does eating less often lower insulin in a way that makes you lose weight?

Yvette d'EntremontBS chemistry, MSc forensic science (self-stated, not independently verified) · science writer, former analytical chemist

No. Meal frequency does not directly affect weight, and where an eating window helps someone it helps by making a lower calorie intake easier to hold. She grants that fasting lowers insulin and denies that this is the route to the weight loss.

What it rests onHer Daily MOS column of 12 Jun 2021. She grants part of the mechanism, writing that lower insulin production is one of the known effects of fasting and that its long-term influence is hard to project, with the clearest effects in animal studies. On weight she says a veritable stack of studies show meal frequency itself does not directly affect weight, and puts the observed effect down to how well people stick to it. She names no individual study, as in the rest of her post-2021 column. She gives permission in the same paragraph: if it works for someone and their doctor is fine with it, it can be perfectly healthy.

Jason FungMD · nephrologist, Scarborough Health Network, Toronto (CPSO #70179, independent practice since 29 May 2001)

Yes. Insulin is the primary driver of obesity, so lowering it is the best route to treating obesity, and fasting lowers it further than a carbohydrate-free diet can.

What it rests onHis article 'Power: Fasting vs Low Carb, Fasting 26', 17 Mar 2016. His closing sentences are 'Insulin is the primary (but not the only) driver of obesity. Therefore, for most people, reducing insulin is the best method of treating obesity.' He ranks the tools in the same passage: carbohydrate-free diets are a powerful way to reduce insulin, and if that does not work, intermittent fasting is more powerful again. The parenthesis 'but not the only' is his own, and it is the difference between what he says and what his critics answer. The same passage goes on to a much stronger claim, that type 2 diabetes is entirely reversible and medication unnecessary, which is a separate question and not what this disagreement is about.