Not sure if you heard or read it, but high-fat diets made headlines again recently. The stories painted a rosy picture of keto, suggesting it helps people lose liver fat. On the surface, it looks impressive, especially since fatty liver affects more than one third of adults in the United States.

So let's look at what the study actually found, what's really happening in your body on keto, and what decades of research say about high-fat eating and your liver.

What the keto study found

The study, published in Cell Metabolism in August 2026, followed 42 adults with obesity, prediabetes, and fatty liver for about four to five months. Each person was assigned to one of three diets:

1 - Keto: 73% fat and only 4% carbohydrate

2 - Mediterranean: 35% fat and 50% carbohydrate

3 - Low-fat, plant-forward: 15% fat and 70% carbohydrate

The researchers supplied all the food and adjusted calories so everyone lost about 10% of their body weight. Liver fat dropped by 67% in the keto group and by 45% in both the Mediterranean and plant-forward groups.

What the headlines left out

Every group lost a lot of liver fat. That's the part that didn't make the headlines. The plant-forward group cut nearly half of their liver fat too, while eating 70% of their calories from carbohydrates.

It was also a small study of 42 people, it lasted only a few months, and all the meals were prepared for them. That's very different from eating keto at home for years.

What's really happening on keto

High-fat diets are automatically low in carbohydrates. Your brain and spinal cord run best on glucose from carbohydrates. In emergencies, your brain can use ketones, but that's a backup system, not a healthy long-term fuel.

Think of ketones like a backup generator during a power outage. It keeps the lights on, and you're glad to have it. But you wouldn't want to run your house on a generator for years.

Your body is coping, not healing

With very few carbohydrates coming in, insulin drops and glucagon rises. Glucagon tells your liver to release stored fuel, so the liver sends out fat and a little stored glucose. In the keto group, glucagon rose the most and insulin fell the most.

Without carbohydrates, your body's preferred fuel, blood sugar doesn't rise much after meals. Your body switches to its backup fuel. Blood sugar falls, A1c drops, and weight loss is likely. It looks good on paper, but it's not healing. It's your body coping.

In all that body busyness, liver fat goes down in the short term, and that's what the study measured.

What decades of research show

Over the long run, research points the other way. Diets high in saturated fat increase liver fat. In one study in Diabetes Care, adults who ate an extra 1,000 calories a day for three weeks gained the most liver fat when those calories came from saturated fat. Their liver fat rose about 55%, and they became more insulin resistant.

Why liver fat matters

More liver fat makes your liver insulin resistant. Insulin resistance shows up as higher blood sugar, higher A1c, higher LDL cholesterol, and higher liver enzymes on your lab work.

All of this fuels inflammation. Chronic inflammation is linked to a higher risk of heart attack, stroke, and type 2 diabetes, and it plays a role in autoimmune conditions like rheumatoid arthritis, Hashimoto's thyroiditis, psoriasis, and inflammatory bowel disease.

That's why I say high-fat diets offer short-term glory but long-term disaster.

What actually helps your liver

This was one small, short study, not decades of research. It doesn't change what we know.

The whole-food, high-fiber way of eating I teach reduces and can even eliminate liver fat. It lowers blood sugar and A1c. It lowers cholesterol. It encourages weight loss. And it improves your overall health instead of stressing your liver. If you want to dig deeper, I wrote about what most people aren't told about fatty liver.

Start with fiber

If you want one simple thing to focus on this week, add more fiber to your meals. Fiber slows down how fast sugar enters your blood, helps lower cholesterol, and feeds the helpful bacteria in your gut. These are easy ways to support your liver, your blood sugar, and your overall metabolic health.

Try this tomorrow morning: top your oatmeal with a handful of berries and a spoonful of ground flaxseed. At lunch, toss a scoop of chickpeas or black beans onto your salad. Oatmeal is a great choice all year, and here's why.

If blood sugar is on your mind

If improving your blood sugar is on your mind, take a look at Diabetes Rescue. It's my program to lower blood sugar, with the goal of type 2 diabetes remission, using simple, science-based steps that fit real life. You can learn more and join the waitlist at peggykraus.com/rescueme.

Have you tried keto, or been tempted to? I'd love to hear what you noticed!

Sources

1 - Cell Metabolism, 2026: ketogenic vs. Mediterranean vs. low-fat plant-forward diets and liver fat (ScienceDaily summary)

2 - Diabetes Care, 2018: saturated fat is more metabolically harmful for the human liver than unsaturated fat or simple sugars

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