February 02, 2026 | Source: BBC Science Focus | by Hatty Willmoth

Eating oats – and not much else – for two days straight can have lasting benefits for your metabolic health, according to a recent study.

A group of 17 adults ate 300g (10.5oz) of oatmeal per day, made with water rather than milk and optionally topped with fruit or vegetables – and nothing else, for two days.

As a result, the participants lost around 2kg (4.4lbs) of weight each, and their LDL (‘bad’) cholesterol fell by 10 per cent on average. Gut health and blood pressure also improved, with these gains still evident six weeks later.

Researchers from the University of Bonn, Germany, compared this brief intervention with a longer, six-week diet in which another 17 participants added 80g (2.8oz) of oats per day to their usual meals.

That longer approach proved less effective, suggesting the metabolic benefits seen in the study were driven by the short, intensive oat-only phase rather than simply adding oats to an otherwise normal diet.