Bread is said to break the waistline. But it seems that at the same time it can make you happy. A new research at the University of York and Hull York Medical School has established the connection between depression and low levels of folate (also called vitamin B9), which comes from vegetables (leaf vegetables, beans, cereals, sunflower seeds).

The team led by Dr Simon Gilbody reached this conclusion based on their review of 11 previous researches made on 15,315 subjects. In May 2007, the Food Standards Agency recommended to UK Health Ministers the introduction of mandatory supplementing of either bread or flour with folic acid to impede neural tube defects, which can lead to miscarriage, neonatal death or lifelong disability. To that list the anti-depression effect is added.

"Our study is unique in that for the first time all the relevant evidence in this controversial area has been brought together. Although the research does not prove that low folate causes depression, we can now be sure that the two are linked.
Interestingly, there is also some trial evidence that suggests folic acid supplements can benefit people with depression. We recommend that large trials should be carried out to further test this suggestion." said Gilbody.

Recently, the same research team has also discovered that people with depression commonly have a gene that makes them process folate less efficiently. Folate has been connected to the production of serotinin, the "feel good" good brain hormone. This gene explains why extra folic acid is beneficial for people with depression.

Serotonin plays an important role in the regulation of anger, aggression, body temperature, mood, sleep, vomiting, sexuality and appetite. Serotonin shortage leads to an increase in aggressive and angry behaviors, depression, obsessive-compulsive disorder, migraine, irritable bowel syndrome, tinnitus, fibromyalgia, bipolar disorder, anxiety disorders and intense religious experiences.