Summary: In a 12-month trial in type 2 diabetes or prediabetes, both a low-carbohydrate high-polyunsaturated-fat diet and a healthy Nordic diet reduced liver fat similarly versus usual care, but only the Nordic diet further improved weight, HbA1c, triglycerides, inflammation, and liver enzymes.
PICO Summary
| Element | Detail |
|---|---|
| Population | 150 adults with prediabetes or type 2 diabetes (55%); three-arm ad libitum randomised trial over 12 months, Sweden (NAFLDiet). |
| Intervention | An anti-lipogenic low-carbohydrate high-polyunsaturated-fat diet (LCPUFA, n=54) or a low-fat healthy Nordic diet rich in whole grains (HND, n=51). |
| Comparison | Usual care (n=43). |
| Outcome | Liver fat fell similarly with both diets versus usual care (LCPUFA -1.46%; HND -1.76%), with no difference between the diets. Both reduced LDL-cholesterol similarly versus usual care. However, only the Nordic diet further reduced body weight, HbA1c, triglycerides, inflammation, and liver enzymes; the LCPUFA diet was no better than usual care for weight or HbA1c. |
NAFLDiet: diet and liver fat in type 2 diabetes
RCT · type 2 diabetes / prediabetes · 12 months
Both diets cut liver fat similarly versus usual care, but only the healthy Nordic diet also improved body weight, HbA1c, triglycerides, inflammation, and liver enzymes.
Expert Commentary
This is a strong year-long trial with a clinically meaningful primary outcome, liver fat measured rigorously, and its nuanced result deserves accurate reporting rather than a blanket both-diets-worked summary. On the primary endpoint the two diets were equivalent and both beat usual care, lowering liver fat to a similar degree, and both lowered LDL similarly, with the polyunsaturated-fat emphasis sensibly avoiding the saturated-fat concerns of traditional low-carbohydrate approaches. But the secondary outcomes separate them clearly: only the Nordic diet improved body weight, HbA1c, triglycerides, inflammation, and liver enzymes, while the low-carbohydrate high-PUFA diet was no better than usual care for weight or glycaemia. So for the broader cardiometabolic picture the Nordic pattern was superior, even without intentional energy restriction. Limitations include the absence of liver histology, so fibrosis effects are unknown, varying adherence as in all diet trials, and a Swedish population and food culture. Can I use this with my patients? Yes, with a steer. Both diets reduce liver fat and are reasonable structured options over generic advice, but where I want simultaneous benefit on weight and glycaemia I would favour a Nordic-style or comparable whole-grain, fish, and plant-oil pattern, ideally with dietitian support, rather than assuming the low-carbohydrate route delivers equal metabolic gains.
References
Fridén M, Rosqvist F, Kullberg J, et al. Effects of an anti-lipogenic low-carbohydrate high polyunsaturated fat diet or a healthy Nordic diet versus usual care on liver fat and cardiometabolic disorders in type 2 diabetes or prediabetes: a randomized controlled trial (NAFLDiet). Nat Commun. 2025;16(1):11130. doi:10.1038/s41467-025-65613-2