How what you eat affects your brain
I wrote this post the Addictive Brain, originally posted here.
The brain is a very complex organ and requires a lot of resources from the body. I am a neuroscientist that studies the brain and how what we eat impacts brain function.
The component of nutrition that my research focuses on is called folic acid, which is a B-vitamin. Folic acid is a water-soluble vitamin, meaning that it does not stay in our body for very long, so we need a constant intake. The bacteria in our gut makes a bit of folic acid, but not enough to meet our body’s requirements. The food that we eat is a good source of folic acid. Food like leafy greens, lentils, and liver are all a good source of folic acid.
Most people know folic acid because of its’ protective role during early brain development. Women that are of child bearing age are recommended to take folic acid prior to getting pregnant because the vitamin helps close the neural tube. The neural tube is future brain and spinal cord. If the neural tube does not close, it can lead to the development of neural tube defects (NTDs) in babies, such as spina bifida. To prevent the NTDs, mandatory folic acid fortification laws were put into place in 1998 in both the US and Canada, as well as other countries. It is important to note that since 1998 there has been a reduction in the number of NTDs in both Canada and the US.
To understand how folic acid impacts brain function, my research uses mice. I am going to share with you 2 studies that have examined the role of maternal dietary folic acid intake on offspring brain and behavior function.
In the first study, female mice were put on a folic acid deficient diet prior to pregnancy and remained on the same diet after they gave birth. When the pups were 3-weeks-of-age, I tested their memory function. Three-week-old mice are equivalent to young adults. I found that pups were on a folic acid deficient diet had impaired memory compared to control diet. These mice also had changes in the area of the brain called the hippocampus, which is well known for its’ role in learning and memory. In hippocampi of folic acid deficient diet pups, I found reduced levels of acetylcholine, a neurotransmitter. These findings suggest that maternal folic acid impairs brain function after birth. These data suggest that folic acid is may not only needed prior to pregnancy, but also during pregnancy.
Last year, we published a study investigating whether too much maternal folic acid is associated with changes in the neurodevelopment of offspring. Using a mouse model of maternal over supplementation of folic acid we report that male offspring from mothers that were fed high levels of folic acid had impaired memory and brain development. These are some of the first results showing how maternal over supplementation with folic acid may affect early neurodevelopment. More studies are required to further dissect the mechanisms as well as determine if the benefits continue into adulthood. As someone wise once said, everything in moderation.