Is keto harmful after a week? It might be for a mouse

Adorable mouse isolated on white background

Have you seen the headlines that a keto diet only works well in small doses, and otherwise it is harmful? We have too. And if you want to feed your pet mice hydrogenated soybean oil, you better pay close attention. But, if you are a human eating a real food keto diet, then you can keep going. There is nothing to see here.

Nature Metabolism: Ketogenesis activates metabolically protective γδ T cells in visceral adipose tissue

Once again, we run into the unfortunate, attention-grabbing news headlines leaving out the most important part of a study. In this case, the study did not include a single human subject. As I’ve explained in prior posts, assuming results from research where mice were fed a synthetic mouse chow applies to humans is a stretch at best.

As several mentioned on Twitter, the strain of mice used for this study are prone to obesity and diabetes. So, not only are we not dealing with humans, but we are dealing with nonhumans designed to get sick faster.

And, as Dr. Ted Naiman pointed out in his Twitter post, the so-called ketogenic diet fed to the mice in the study consisted mostly of hydrogenated soybean oil and contains just 10% of calories from protein.

If you’re still interested in the study results, the authors found that certain immune cells increased in the first week on a keto diet and there was also a reduction in blood sugar levels. Both are good news. But after a week on the diet, the mice ate more fat than they could effectively burn, and their blood sugars rose.

So, again, be careful over-feeding your mice this particular chow. But, if you are a human who wants to eat a well-balanced diet of low-carb foods, I find it hard to imagine this study says anything of interest for you.

Confusion about study quality is one of many reasons why, at Diet Doctor, we don’t just cite evidence, we also rate the quality of the evidence. Whether we agree with the results or not, animal studies are rated as very weak evidence. We just wish that news headlines reflected this as well.

Thanks for reading,
Bret Scher, MD FACC


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