There are a number of vitamins and other nutrients that can directly impact neurotransmitter function in our body, particularly those transmitters that affect mood. For example, B vitamins are important for the metabolism of amino acids into neurotransmitters, such as serotonin, which is a mood elevator. If you’re feeling depressed without any good reason, you may just be slightly low in your B-vitamin intake and need a boost so your body can produce the right neurotransmitters. Foods that are rich in B vitamins include leafy greens, whole grains, beans, nuts and shellfish.