Long-Term Keto May Damage Your Body: What This New Study Reveals

Neuroscience just posted this study a couple of hours ago, and it immediately caught my eye. As a Doctor of Clinical Nutrition, I’m always intrigued by research that examines the long-term effects of popular diets — especially ones as trendy (and controversial) as keto.

The Promise — and the Problem — With Keto

The ketogenic diet has been marketed for everything from rapid weight loss to mental clarity. And in the short term, it can deliver results. People often experience quick fat loss, reduced appetite, and more stable energy once they adapt to using fat for fuel.

But here’s the thing — any diet that requires you to cut out entire food groups completely or forces your body into a non-natural metabolic state (like ketosis) can have consequences if done for too long.

And this new study highlights exactly that.

What the Study Found

In this recent mouse-model study, researchers examined what happens when animals are fed a ketogenic diet for an extended period — about eight months, which is roughly equivalent to decades in human lifespan terms.

The results weren’t encouraging:

• Fatty liver buildup: The mice developed hepatic lipid accumulation — essentially, their livers began storing excess fat, leading to signs of liver dysfunction, particularly in males.

• Disrupted glucose regulation: The pancreatic β-cells (which secrete insulin) showed signs of stress and impairment, resulting in glucose intolerance.

• Partial recovery after stopping keto: Some of the adverse effects reversed once the diet ended — a small silver lining — but the researchers noted that specific metabolic changes lingered.

The takeaway? Even though this study was done in mice, it raises important questions about what prolonged ketogenic dieting might do to human metabolism over time.

Why This Matters

Our bodies are incredibly adaptive — they can switch fuel sources and compensate for dietary extremes for a while. But the body’s adaptability doesn’t mean it’s meant to live in a constant state of restriction.

Short-term benefits don’t always equal long-term health. Living in perpetual ketosis forces the body into what’s essentially a survival mode, prioritizing immediate energy management over long-term balance.

That’s not how sustainable health works.

My Perspective as a Clinical Nutritionist

When I work with patients, I always encourage them to think about the why behind their food choices. If a diet feels extreme or unsustainable, it probably is.

Keto can have therapeutic value — for example, in certain medical settings like epilepsy management or metabolic disorders — but using it casually as a long-term “lifestyle diet” may not be without risks.

Before starting (or continuing) any restrictive eating pattern, ask yourself:

• Is this truly sustainable for my body and lifestyle?

• Am I nourishing my metabolism — or fighting against it?

• What might this look like for me in 10 years?

Listen to your body — and the science. Sustainable health rarely comes from extremes.

If you’re considering keto or any restrictive diet, talk to a qualified nutrition professional who can help tailor an approach that supports both your short-term goals and your long-term wellbeing.\

👉 Read the original study here