A glossary of health terminology: I to L

In your quest to eat healthy, you may come across words you don't recognize. Here are a couple — starting with the letter 'I' — and the definition for each one.

Incomplete proteins:

Proteins, usually from plant sources, that lack one or more essential amino acids.

Indoles:

Partially responsible for the strong taste of broccoli and brussels sprouts, indoles are a class of glucosinolate phytochemicals present in cruciferous vegetables and may stimulate cancer-fighting enzymes.

Indole-3 carbinol:

A well-studied compound and a member of the glucosinolate phytochemical family, indole-3 carbinol is particularly abundant in broccoli and oher cruciferous vegetables. It may offer protection against hormone-dependent cancers, such as breast cancer. Insulin: A hormone that regulates carbohydrate metabolism.

Isoflavones:

Found primarily in soy foods, isoflavones are a major class of phytoestrogens, plant chemicals with mild estrogen activity. Genistein and daidzein are the most prominent isoflavones. Soy isoflavones are being studied for their potential to ease menopause symptoms and to protect against osteoporosis-related fractures. Alzheimer's disease, high cholestrol and hormone dependent cancers, such as breast and prostate cancer.

Ketones:

Potentially toxic waste products produced from the body's partial burning of fatty acids for fuel.

Lecithin:

A phospholipid constituent of cell membranes and lipoproteins, lecithin is a natural emulsifier that helps stabilize cholesterol in the bile. Lecithin is not an essential nutrient, because it is synthesized by the liver.

Lentinan:

A polysaccharide (carbohydrate compound) extracted from shiitake mushrooms, lentinan may have the potential to enhance immunity, as well as to protect against cancer, high blood pressure and high cholesterol.

Lignans:

Phytoestrogens with mild estrogen-like activity. They may have anti tumour effects, anti microbial benefits and provide relief from PMS and protection against osteoporosis. Food sources include flaxseeds (group up), flaxseed oil, soy foods and grains.

Limonene:

A phytochemical found in lemons, limes and oranges. Now being studied for its ability to inhibit tumours and protect the lungs from disease. L

Inoleic acid:

One of the omega-3 essential fatty acids.

Lipid:

A fatty compound made of hydrogen, carbon and oxygen, lipids are insoluble in water. The chemical family includes fats, fatty acids, cholesterol, oils and waxes.

Lipoprotein:

A combination of a lipid and a protein that can transport cholesterol in the bloodstream. The main types of high density (HDL), low density (LDL) and very low density (VLDL).

Low-density lipoproteins (LDLs):

These abundant, so-called "bad" lipoproteins carry most of the circulating cholesterol; high levels are associated with atherosclerosis and heart disease since this form of cholesterol builds up on artery walls.

Lutein and zeaxanthin:

Found in foods that are bright yellow, orange and green, lutein and zeaxanthin are pigments in the carotenoid family that are linked to reduced risk for mascular degeneration and cataracts. Lutein is found in green leafy vegetables such as collard greens, kale, spinach and watercross, as well as corn and egg yolks. Zeaxanthin is found in greens, red peppers and corn.

Lycopene:

A powerful antioxidant that lends red colour to numerous foods, lycopene is particularly abundant in tomatoes and tomato products. Studies have show lycopene to be protective against prostate cancer, lung cancer and heart disease.