Egg yolks are an important brain food, as they provide nutrients which are essential for proper brain functioning in terms of mental health, nervous system health and cognitive activity. In fact, egg yolks may be one of the most important foods for brain health, as they provide choline, a nutrient which serves multiple integral brain functions and is relatively rare in other foods.
Egg yolks are one of the richest dietary sources of choline, an essential nutrient which, while technically an amino acid, is often classed with B-complex vitamins. Two large egg yolks provide a little over 230 milligrams of choline, or about half of your daily needs. Choline aids brain function by helping maintain the structure of brain cell membranes. Choline is also a precursor for the neurotransmitter acetylcholine, which is needed to relay messages from the brain to nerves and muscles. Choline is especially important brain food for a developing baby in the womb; consuming choline during pregnancy assists in fetal brain development and protects against fetal brain defects.
Egg yolks are a rich source of various vitamins and minerals needed for proper brain functioning. In particular, egg yolks are a good source of B vitamins including B-12, which serves numerous brain functions including formation of myelin -- a substance that aids transmissions between nerve cells -- and protection against mental health problems; B-5, needed to maintain nervous system health; B-6, which is involved in the production of various neurotransmitters; and biotin, a deficiency of which can cause nervous system-related movement and vision problems. Moreover, egg yolks provide the essential mineral and brain nutrient, zinc, which serves antioxidant functions in the brain.
Protein and Amino Acids
Besides choline, egg yolks also provide other amino acids, or protein building blocks, to offer a complete protein package. Two egg yolks provide approximately 5.4 grams of high-quality protein for only 108 total calories. Protein, in general, is an important source of brain fuel, and the particular amino acids provided by egg yolks help the brain produce important neurotransmitters. Some amino acids in egg yolks include: aspartic acid, needed to make the neurotransmitter asparate; phenylalanine, used to make mood-related neurotransmitter, dopamine; and tryptophan, which helps produce another important neurotransmitter for mood regulation, serotonin.
Other Brain Foods
You can also obtain the brain health-promoting nutrients in egg yolks from other dietary sources. For example, beef liver and wheat germ also provide choline and B vitamins. In general, animal products -- i.e., meat, dairy and fish -- are all good providers of B vitamins as well as complete proteins. Various plant foods, such as beans, nuts, seeds, whole grains and green leafy vegetables, also offer many of the amino acids needed for neurotransmitter production, along with micronutrients that are important for proper brain functioning like zinc, vitamin C and vitamin E. Lastly, cold-water fish, walnuts and flax seeds are good brain foods, as they provide essential fatty acids your brain needs.