A new study suggests that a strict ketogenic diet – high in fat, low in carbs – can normalize blood sugar levels in mice with hyperglycemia and even enhance the benefits of exercise. Researchers found that mice on keto not only had their blood sugar restored to normal within a week but also showed improved aerobic capacity and muscle endurance when they exercised. The findings add weight to the idea that diet and exercise work together in ways we’re only beginning to understand.
The Study’s Key Findings
The research, conducted by scientists across several US institutions, focused on mice with high blood sugar. The keto diet caused a rapid normalization of their blood glucose, essentially reversing diabetes-like symptoms. But the real surprise came when these mice were put through aerobic exercise: their VO2 peak (a measure of oxygen use during exertion) increased, meaning they could work out harder and longer.
The diet didn’t just correct blood sugar; it fundamentally changed muscle physiology, making them more efficient at using oxygen. This improvement wasn’t seen in mice with already healthy blood sugar levels, suggesting the diet’s benefits are targeted. Interestingly, performance didn’t improve until carbs were reintroduced, hinting that complete carbohydrate restriction isn’t necessarily ideal for peak performance.
Why This Matters
This study builds on previous work showing that high blood sugar impairs exercise gains. By fixing the blood sugar issue, the keto diet appears to “unlock” the body’s ability to respond better to physical activity.
“What we’re really finding… is that diet and exercise aren’t simply working in isolation. There are a lot of combined effects, and so we can get the most benefits from exercise if we eat a healthy diet at the same time.” – Sarah Lessard, Virginia Tech Carilion.
For people with diabetes, maintaining aerobic capacity is crucial for preventing complications. This study suggests keto could be one way to achieve that. But experts caution that this was an extreme diet in mice, and human trials are needed.
Caveats and Future Research
While promising, these results are preliminary. The keto diet used was particularly strict, and the findings haven’t been replicated in humans. The researchers acknowledge that keto is difficult to maintain long-term, and other dietary approaches – like the Mediterranean diet – might be more sustainable.
The study also suggests that simply lowering blood sugar is the key, regardless of how it’s done. Human trials are already planned to confirm these findings and explore whether similar effects occur in people with high blood sugar.
Ultimately, this research reinforces the complex interplay between diet, exercise, and metabolic health. It highlights that optimizing both factors, rather than focusing on one in isolation, is likely the most effective path to improved well-being.
