Cholesterol is a waxy substance your body uses to repair cells, make hormones, synthesize vitamin D from sunshine and make bile that aids in digestion. Your liver manufactures cholesterol whether or not you consume any in food; when you consume it, the liver reduces its production. In some people, however, the liver does not lower production; in other cases, the diet contains an excessive amount of cholesterol. Either of these can lead to undesirable amounts of cholesterol in the blood, increasing the risk for heart disease.
Lipoproteins, LDL and HDL
Lipoproteins are composed of proteins and fat or fat-like substances. Low-density lipoprotein, or LDL, transports cholesterol from your liver to tissues that use it, while high-density lipoprotein, or HDL, takes excess cholesterol back to your liver for removal. If you don't have enough HDL, excess LDL continues to circulate in your blood where it is exposed to unstable molecules called free radicals. Free radicals cause changes to LDL, allowing it to penetrate blood vessel walls. The resulting inflammatory response causes plaque formation, which leads to atherosclerosis.
Cholesterol Test Results
Cholesterol test results include levels for HDL and LDL specifically. For adults, HDL should be 60 mg/dL or higher. Mayo Clinic.com reports levels less than 40 mg/dL for men and less than 50 for women are a risk factor for heart disease. LDL should be less than 100 mg/dL, but if you're at high risk of heart disease, the level should be below 70. A level of 130 to 159 is borderline high, while a level of 160 to 189 is considered high and 190 or above is considered very high.
HDL and Lifestyle
You can raise HDL through a healthier lifestyle. If you smoke, calling it quits can increase HDL by as much as 10 percent. HDL can rise with moderate alcohol intake -- two drinks a day for men, one drink for women and people over 65. If you don't drink, however, there are other ways to raise HDL. Losing weight raises it, as does aerobic exercise. Give up saturated fats for monounsaturated and polyunsaturated fats; avoid trans fats completely. Finally, a diet rich in omega-3 fatty acids helps improve both HDL and LDL levels. Good dietary sources for omega-3 fatty acids include nuts and cold-water fish, such as salmon, mackerel and sardines.
LDL and Lifestyle
Most things that raise HDL also lower LDL, including losing weight, exercising and avoiding saturated and trans fats. Eat whole grains, vegetables and fruits to increase fiber. Soluble fiber helps remove cholesterol from your body. A diet rich in whole grains, veggies and fruits also aids weight loss and provides a rich supply of antioxidants that help counteract the effect of free radicals on LDL, thereby preventing the formation of arterial plaque. If your LDL stays high after making lifestyle changes, talk to your doctor about medication.
