galanin : A neurotransmitter released when fat stores need filling up.

genistein: A phytoestrogen found in extracts of soybeans, red clover, and kudzu root.

ghrelin: From the Indo-European root meaning growth, ghrelin is secreted in the lining of the stomach.

glucosamine : A raw material your body needs to lubricate joints and build and maintain cartilage.

glutamic acid : A nonessential amino acid abundant in both animal and vegetable proteins and found in high concentrations in the human brain.

glycemic index : A system of ranking carbohydrate foods according to how fast they’re digested and enter the bloodstream as glucose.

glycine : A nonessential amino acid that occurs in protein foods and comes from choline in the liver and the amino acids threonine or serine.

glycogen: A carbohydrate in storage form in your body.

gout : A form of arthritis that affects 9 men for every one woman caused by uric acid crystals collecting in the spaces around joints.