Researchers tested two different eating plans against normal eating habits in 150 people with prediabetes or type 2 diabetes. One diet replaced carbs with healthy plant-based fats, while the other focused on whole grains and Nordic-style foods. After one year, both diets reduced fat buildup in the liver compared to regular eating. The Nordic diet worked even better for weight loss and blood sugar control. The good news: people didn’t have to count calories—they could eat as much as they wanted while following these plans.

The Quick Take

  • What they studied: Can two specific eating patterns reduce fat stored in the liver and improve blood sugar and cholesterol in people with prediabetes or type 2 diabetes?
  • Who participated: 150 adults (about half men, half women) with either prediabetes or type 2 diabetes, averaging middle age, studied at a hospital in Sweden for 12 months
  • Key finding: Both special diets reduced liver fat by about 1.5-1.8% more than regular eating. The Nordic diet also helped people lose more weight and control blood sugar better, without requiring calorie counting.
  • What it means for you: If you have prediabetes or type 2 diabetes, switching to either of these eating patterns may help reduce dangerous fat in your liver and improve your health markers. The Nordic diet appears to offer extra benefits for weight and blood sugar. Talk to your doctor before making major diet changes.

The Research Details

This was a rigorous randomized controlled trial, which is considered one of the strongest types of research. Researchers randomly divided 150 people into three groups: one eating a low-carb, high plant-based fat diet; one eating a Nordic-style whole-grain diet; and one continuing their normal eating habits. The study lasted 12 months, and people in the special diet groups could eat as much as they wanted—they weren’t restricted on portion sizes. Doctors measuring the results didn’t know which diet each person was following, which helps prevent bias.

The researchers chose these two diets because previous studies suggested that plant-based fats might be better for liver health than other fats, and whole-grain diets have long been associated with better health. They wanted to see which approach worked best for people with blood sugar problems and fatty liver disease.

Participants were carefully matched by sex and whether they had prediabetes or full type 2 diabetes to make sure the groups were as similar as possible at the start.

This study design is important because it tests real-world eating patterns that people can actually follow, rather than extreme diets. By allowing people to eat freely without counting calories, researchers could see if these diets naturally lead to better health. The blinding of outcome assessors prevents researchers from unconsciously favoring one group’s results over another.

This study has several strengths: it was published in a top-tier scientific journal (Nature Communications), used proper randomization, included blinding of assessors, and had a reasonable sample size. The study was completed as planned with low dropout rates. However, it was conducted in Sweden with a relatively small sample, so results may vary in different populations. The 12-month timeframe is good for seeing real changes, though longer studies would show if benefits last.

What the Results Show

Both special diets successfully reduced liver fat compared to regular eating. The low-carb, high plant-based fat diet reduced liver fat by 1.46%, while the Nordic diet reduced it by 1.76%—both statistically significant improvements. These reductions may seem small as percentages, but they represent meaningful decreases in a dangerous type of fat that builds up in liver cells.

The Nordic diet showed additional benefits beyond liver fat reduction. People following the Nordic diet lost more weight and had better blood sugar control (measured by HbA1c, a test showing average blood sugar over three months) compared to the other two groups. This suggests the Nordic diet’s emphasis on whole grains and plant-based foods may have broader metabolic benefits.

Both diets similarly reduced LDL-cholesterol (the “bad” cholesterol) compared to regular eating. However, only the Nordic diet reduced triglycerides (another type of blood fat), inflammation markers, and liver enzymes that indicate liver stress. This suggests the Nordic diet provided more comprehensive metabolic improvements.

Safety was excellent across all groups, with only four serious adverse events total, distributed evenly among the three groups, indicating both diets were well-tolerated.

The study revealed that the low-carb, high plant-based fat diet and the Nordic diet worked through somewhat different mechanisms. While both reduced liver fat and LDL-cholesterol, the Nordic diet’s whole-grain focus appeared to provide superior benefits for weight management and blood sugar regulation. The reduction in liver enzymes with the Nordic diet suggests it may reduce liver inflammation more effectively. These secondary findings suggest that for people with type 2 diabetes specifically, the Nordic approach may offer more complete metabolic benefits.

Previous research suggested that plant-based fats (polyunsaturated fats) were better for liver health than saturated fats, and this study confirms that principle. However, this is one of the first studies directly comparing a low-carb, high plant-based fat approach to a traditional whole-grain diet in people with diabetes and fatty liver disease. The findings align with growing evidence that whole-grain, plant-forward diets benefit metabolic health, while also validating that plant-based fats can be beneficial when replacing carbohydrates.

The study included only 150 people from one hospital in Sweden, so results may not apply equally to all populations worldwide. The 12-month timeframe shows good short-term results, but we don’t know if benefits continue beyond one year. The study didn’t track exactly what people ate, only which diet group they were assigned to, so we can’t be certain people followed the diets perfectly. Additionally, the study couldn’t determine the ideal ratio of plant-based fats to carbohydrates, as it only tested one specific approach. Finally, people who volunteer for diet studies may be more motivated than the general population, which could affect results.

The Bottom Line

For people with prediabetes or type 2 diabetes: Consider adopting either a low-carb diet emphasizing plant-based fats or a Nordic-style whole-grain diet. The Nordic diet appears to offer stronger benefits for weight loss and blood sugar control (moderate-to-high confidence based on this study). Neither diet requires calorie counting, making them potentially easier to follow long-term. These recommendations are based on solid research but should be discussed with your healthcare provider, especially if you take diabetes medications, as improved blood sugar control may require medication adjustments.

This research is most relevant for people with prediabetes or type 2 diabetes, particularly those with fatty liver disease or metabolic syndrome. It may also interest people with high cholesterol or triglycerides. People with severe liver disease, kidney disease, or those taking specific medications should consult their doctor before making major diet changes. The findings are less directly applicable to people without blood sugar problems, though the general principles may still offer health benefits.

Based on this study, you can expect to see measurable improvements in liver fat within 12 months of consistent diet adherence. Weight loss and blood sugar improvements may appear within 3-6 months. However, individual results vary significantly based on starting point, adherence, and other lifestyle factors. Consistency matters more than perfection—gradual, sustainable changes are more likely to produce lasting benefits than strict short-term efforts.

Want to Apply This Research?

  • Track weekly average blood sugar readings (if you monitor at home) and body weight weekly. For liver health, note energy levels and any changes in digestive comfort. If possible, work with your doctor to recheck liver enzymes and ultrasound every 3-6 months to objectively measure liver fat reduction.
  • Start by identifying which diet pattern appeals to you more: the Nordic approach (emphasizing whole grains, fish, berries, and vegetables) or the low-carb plant-fat approach (replacing grains with nuts, seeds, avocados, and plant oils). Use the app to log meals according to your chosen pattern, focusing on adding more of the recommended foods rather than restricting calories. Set a goal to follow your chosen diet for at least 3 months before evaluating results.
  • Use the app to track food choices daily, noting adherence to your chosen diet pattern. Monthly, review your weight trend and any available blood sugar readings. Every 3 months, assess energy levels, how you feel, and any changes in symptoms like bloating or fatigue. Schedule lab work with your doctor every 6 months to measure objective markers like HbA1c, cholesterol, and liver enzymes.

This research suggests potential benefits of specific diets for people with prediabetes and type 2 diabetes, but individual results vary. This information is educational and should not replace medical advice from your healthcare provider. Before starting any new diet, especially if you take diabetes medications or have other health conditions, consult your doctor. Dietary changes may affect medication needs and blood sugar levels. This study was conducted in a specific population and may not apply equally to all individuals. Always work with your healthcare team to monitor your health during dietary changes.