Basic concepts

Amino acids

Amino acids are the building blocks of proteins. Some are essential because the body cannot make enough of them.

Body weight changes over time according to the relationship between energy from food and energy the body uses.

Fats are energy-dense nutrients that support cell membranes, hormones and absorption of fat-soluble vitamins.

Glycogen is the body’s storage form of carbohydrate, kept mainly in muscles and the liver.

Hormones are chemical signals that help regulate appetite, energy use, growth, stress, reproduction and many other processes.

Insulin is a hormone that helps move glucose from the blood into cells and coordinates how the body handles energy after eating.

Protein supplies amino acids used to build and repair body tissues and support many internal functions.

Starch is a complex carbohydrate made of glucose chains. It is common in potatoes, rice, grains, pasta, bread and legumes.