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Home > Wellness > Health Library > Carbohydrates, Proteins, Fats, and Blood Sugar
The body uses three main nutrients to function—carbohydrate,
protein, and fat.
These nutrients are digested into
simpler compounds. Carbohydrates are used for energy (glucose). Fats are used for energy after they are broken into fatty acids. Protein can also be used for energy, but the first job is to help with making hormones, muscle, and other proteins.
Type of nutrient
Where it is found
How it is used
Broken down into glucose, used to supply
energy to cells. Extra is stored in the liver.
Broken down into amino acids, used to build
muscle and to make other proteins that are essential for the body to
Broken down into fatty acids to
make cell linings and
hormones. Extra is stored in fat cells.
After a meal, the blood sugar (glucose) level rises as
carbohydrate is digested. This signals the beta cells of the
pancreas to release
insulin into the bloodstream. Insulin helps glucose
enter the body's cells to be used for energy. If all the glucose is not needed
for energy, some of it is stored in fat cells and in the
liver as glycogen. As sugar moves from the blood to
the cells, the blood glucose level returns to a normal between-meal
Several hormones and processes help regulate the blood sugar level
and keep it within a certain range
(70 mg/dL to 120 mg/dL). When the blood sugar level falls
below that range, which may happen between meals, the body has at
least three ways of reacting:
Other hormones can raise the blood sugar
level, including epinephrine (also called adrenaline) and
cortisol released by the
adrenal glands and growth hormone released by the
ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineAdam Husney, MD - Family MedicineSpecialist Medical ReviewerRhonda O'Brien, MS, RD, CDE - Certified Diabetes EducatorColleen O'Connor, PhD, RD - Registered Dietitian
Current as ofJuly 5, 2016
Current as of:
July 5, 2016
E. Gregory Thompson, MD - Internal Medicine & Adam Husney, MD - Family Medicine & Rhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator & Colleen O'Connor, PhD, RD - Registered Dietitian
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