Oats' surprising resurgence in diabetes management rooted in historical use and modern science

Long before insulin’s advent, oats played a pivotal role in diabetes care, a practice now supported by modern research revealing their benefits for insulin sensitivity and gut health.

Long before insulin transformed diabetes care, oatmeal had already earned an unlikely place in treatment. According to a JAMA abstract, the German physician Carl von Noorden promoted an oatmeal-based regimen in 1903, at a time when the approach was met with considerable doubt. The same account says later clinical experience, including work by Dr James B. Herrick, helped persuade many doctors that the diet could do real work in controlling diabetes.

Herrick’s 1908 paper in JAMA described the diet in practical terms and reported that it had value in diabetes management. His findings, together with the broader uptake of von Noorden’s ideas, helped move the so-called Haferkur from curiosity to clinical tool. By the early twentieth century, diet was becoming central to diabetes care, even if the science was still in its infancy.

That historical interest has since been strengthened by modern evidence. A systematic review and meta-analysis published in 2020 found that oat consumption improved insulin sensitivity, glucose metabolism, blood lipid profiles, endothelial function and inflammation, all of which are relevant to the prevention and management of type 2 diabetes and cardiovascular disease. For a food once treated with scepticism, oats now look considerably more respectable in the scientific literature.

The mechanism appears to lie largely in fibre, especially beta-glucan. Oats are a fermentable source of fibre that can be used by gut bacteria to produce short-chain fatty acids with anti-inflammatory effects. Research summarised in the material provided also points to a prebiotic role for oat fibre, helping beneficial bacteria such as Lactobacillus and Bifidobacteria to flourish. That matters because shifts in the gut microbiome are increasingly linked with insulin sensitivity and blood sugar control.

There is also a cautionary note. The NutritionFacts article says some small studies have found that only a few days on an oatmeal-rich diet can lower insulin requirements and improve blood sugar for weeks afterwards, which means people taking glucose-lowering medication could become overtreated without close supervision. The broader lesson is not that oats are a miracle cure, but that they can be a powerful part of a fibre-rich dietary pattern. As the article suggests, the simplest version may still be the best: plain oats, preferably less processed, topped or combined with other whole plant foods.