Bilberry extract, ultra-processed food and liver fat
What it found
In a large UK study, people who ate more ultra-processed food had more liver fat, and in mice with a junk-food-style diet, bilberry extract reduced liver fat and inflammation.
The human and animal parts were separate, and the human part can only show a link, not cause.
What they found
Studies in people
Liver fat in people
Each 10% higher intake of ultra-processed food was linked to a 9% higher risk of MASLD, and to more liver fat and inflammation on MRI scans.
Berry intake in people
People who ate the most berries and the least ultra-processed food had the lowest risk of MASLD, and berry intake changed the link between ultra-processed food and MASLD risk.
FGF21 as mediator
Among 2,911 plasma proteins, FGF21 was the strongest link between ultra-processed food intake and liver fat, and it explained the largest share of that link.
Animal and lab studies
Liver damage in mice
Mice fed the baked Western diet for 16 weeks developed liver fat, inflammation and scarring, and bilberry extract reduced all of these.
Blood sugar in mice
The baked Western diet raised fasting glucose and insulin and worsened glucose tolerance in mice, and bilberry extract brought these back toward normal.
FGF21 in mice and cells
Bilberry extract restored liver FGF21, FGFR1c and beta-Klotho proteins that the diet had lowered, and when FGF21 was knocked down in mouse liver cells, bilberry extract no longer reduced fat buildup.
What the authors conclude
“These findings highlight FGF21 as a potential therapeutic target and suggest that anthocyanin-rich nutritional interventions may offer a promising strategy for mitigating the metabolic consequences of UPF consumption, warranting further validation in clinical settings.”
Also in their conclusions
- They say FGF21 may be a mediator linking ultra-processed food to liver fat buildup.
- They suggest that anthocyanin-rich foods like bilberry may help prevent MASLD, but that this needs testing in clinical trials.
How it was done
The authors wanted to see whether a protein called FGF21 links ultra-processed food to liver fat buildup, and whether a berry extract could protect the liver through that pathway.
They looked at 29,386 UK Biobank participants with MRI liver scans and diet questionnaires. They also fed nine-month-old male mice a baked Western diet with or without bilberry extract (200 mg/kg/day) for 16 weeks, and tested bilberry extract in mouse liver cells in the lab.
What it can’t tell you
- The human part followed people over time, so it can show a link between ultra-processed food and liver fat, not cause and effect.
- The mouse and cell results cannot show what happens in people.
- The berry intake in people was not the same as the bilberry extract given to mice.
Who paid
- Funding
- Funded by National Natural Science Foundation of China; China Association for Science and Technology; Chinese Nutrition Society; Health Commission of Hubei Province 2025-2026 Research Project (from the PubMed record).
- Conflicts
- The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
- Authors work at
- Huazhong University of Science and Technology, China
The paper
- Title
- FGF21 as a Potential Mediator of Ultra-Processed Food-Associated Metabolic Dysfunction-Associated Steatotic Liver Disease and the Protective Effect of Bilberry Extract
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Licence
- CC BY. Words in quotation marks are the authors’; the rest is our summary.
- Cite
- Lv Y, Zhao F, Zhang Y, et al (2026). FGF21 as a Potential Mediator of Ultra-Processed Food-Associated Metabolic Dysfunction-Associated Steatotic Liver Disease and the Protective Effect of Bilberry Extract. Nutrients. doi:10.3390/nu18152430Free full textPubMed 42588053DOI
Summary written 29 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error