A new study published in Microbiome suggests that consuming one medium orange a day may lower the risk of depression by 20%. The research, led by Raaj Mehta at Harvard Medical School, found that citrus stimulates the growth of Faecalibacterium prausnitzii, a type of bacteria found in the human gut. This bacterium is associated with increased levels of serotonin and dopamine, two neurotransmitters linked to mood elevation.
The study analyzed data from over 100,000 women participating in the Nurses’ Health Study II and found that those who consumed more citrus had lower rates of depression. However, it’s essential to note that this effect was specific to citrus consumption and not other fruits or vegetables.
To understand the link between citrus intake and depression, researchers used DNA sequencing results from stool samples to identify species of bacteria in the gut microbiome. They found that F. prausnitzii was more abundant in people without depression, which is inversely correlated with increased levels of this bacterium upon citrus consumption.
The study’s findings suggest that F. prausnitzii may play a role in modulating the association between citrus intake and depression by influencing the production of serotonin and dopamine. These neurotransmitters regulate mood and can be produced by human cells in the gut, although their exact mechanism remains unclear.
While the study’s results are promising, more research is needed to confirm the findings. Dr. Mehta hopes to see a clinical trial conducted to definitively show that eating citrus can lower depression risk or alleviate symptoms. The study’s authors also emphasize the importance of exploring the link between diet and mental health, as researchers continue to uncover the specifics of how food impacts mood.
Source: https://medicalxpress.com/news/2025-02-apples-outlines-orange-day-depression.html