LDL, or low-density lipoprotein, is the best gauge of your risk for heart attack and stroke, even more so than total cholesterol, according to the American Heart Association. An optimal LDL cholesterol level is below 100 milligrams per deciliter.

Your body contains two main types of cholesterol: HDL, or high-density lipoproteins, and LDL, low-density lipoproteins. If your blood has a high concentration of LDL cholesterol, you may have a greater chance of having a stroke or heart attack.

Americans love shrimp in any form -- kebabs, stir-fry and shrimp cocktail are all classic favorites. Although the curled pink seafood is low-fat and an excellent source of protein, it is also an extremely high-cholesterol food.

Serotonin functions as a chemical messenger in the brain. It regulates mood, sleep, appetite and the emotional perception of pain.

Triglyceride levels rise and fall depending on how much fat the body stores. Doctors are generally more concerned about high levels of triglyceride, described as a blood level of 150 mg/dL or higher, than they are about low triglyceride levels. Michael Miller, M.D.

The placenta attaches a fetus to a woman's uterine wall, bringing maternal blood vessels close to fetal vessels. Important nutrients and other positive factors pass from the mother's blood into the fetal blood, helping support fetal growth and development.

Vitamin D plays a well-known role in calcium absorption and bone health. In addition, vitamin D supports immune function, regulates cell growth and helps reduce inflammation. Vitamin D deficiency is a growing health concern. A few foods contain vitamin D naturally, and others are fortified with it.

Numerous conditions or factors can cause low levels of high-density lipoprotein, or HDL, cholesterol. According to MayoClinic.com, HDL cholesterol, or good cholesterol, acts as a cholesterol scavenger, transporting excess cholesterol in the blood back to the liver where it is metabolized, or broken down.

Catchphrases about milk abound in popular culture, thanks to advertising, and while many point out that milk is good for you, they're sometimes vague about the facts.

Cholesterol is a naturally produced, fatlike substance found in cell walls. The lipoproteins HDL and LD typically transport it through the body. Small amounts of cholesterol are needed for the body to function properly, but high levels of cholesterol can increase the risks of heart disease and stroke.

Progesterone plays an important role during pregnancy. After delivery of the baby, the levels of this hormone begin to drop. Breastfeeding causes low levels of progesterone due to the effect of prolactin, which prevents ovulation. Thus, progesterone levels tend to be very low during this time.

The plant compound resveratrol has been linked to an array of health benefits, including cancer prevention, protection against cardiovascular disease and longevity. However, most research done on resveratrol has been limited to the laboratory and clinical trials are lacking.