Scientists Identify a Compound in Tomatoes That May Protect the Liver From Fatty Liver Disease

Researchers at Tufts University have found that phytoene, a lesser-known plant pigment found in tomatoes, may reduce the risk of developing fatty liver disease. So far, however, the effect has been demonstrated only in experiments involving mice.

Phytoene is a colorless compound and a precursor to lycopene, the pigment responsible for the red color of ripe tomatoes. The researchers set out to determine whether phytoene itself might have protective properties.

The study, published in Molecular Nutrition & Food Science, found that mice given phytoene along with a diet high in refined carbohydrates developed significantly less fat accumulation in the liver than animals fed the same diet without the supplement.

The dose of phytoene used in the experiment was roughly equivalent to the amount a person could obtain from three to four medium-sized fresh tomatoes or 100 grams of tomato paste per day.

The scientists believe phytoene may work not by altering the composition of the gut microbiome, but by directly affecting proteins involved in regulating metabolism in the liver. This could help the body use excess fat as an energy source rather than storing it in liver cells.

However, the experiment suggested that phytoene itself may not be the only compound responsible for the protective effect. Mice lacking the enzymes needed to metabolize phytoene had substantially higher levels of the compound in their bodies, yet they did not show the same protective response. This suggests that metabolites produced when phytoene is broken down in the body may play an important role.

“Both lycopene and phytoene are found in significant amounts in tomatoes and tomato-based products. However, previous research has shown that phytoene is actually more readily absorbed by the body,” said Na-Yeon Lee, the study’s lead author at Tufts University.

The researchers also observed differences between male and female mice. Female animals accumulated higher levels of phytoene in their livers, suggesting that biological sex may influence how the compound is absorbed and metabolized.

Metabolic dysfunction-associated steatotic liver disease (MASLD), a condition in which excess fat accumulates in liver cells, affects up to 38% of adults in the United States. Over time, it can cause inflammation and liver damage and may progress to cirrhosis.

The authors emphasize that further research is needed before any protective effect of phytoene in humans can be established. If the findings are confirmed in human studies, phytoene-rich fruits and vegetables could potentially become one component of strategies aimed at preventing metabolic liver disease.