Cholesterol is a waxy, soft substance used to form cell membranes, some hormones. It is contained in fats (lipids) that travel through the bloodstream and enter your cells. While it is important for maintaining a healthy body, high levels of cholesterol in the blood (called
hypercholesterolemia) can lead to the most common cause of death: heart disease.
Cholesterol is carried to and from cells by special carriers called lipoproteins, such as
low-density lipoprotein (LDL) and
high-density lipoprotein (HDL).
LDL
Low-density lipoprotein (LDH) is the major cholesterol carrier in the blood. However, because of poor diet, too much LDL cholesterol can circulate in the blood and cause build up of LDL in the arteries that feed the heart and brain. LDL combines with other substances to form a substance commonly called
plaque, that clogs those arteries resulting in a condition called atherosclerosis. Blood flow can be blocked by this buildup (normally called a clot or
thrombus) which causes a heart attack if the blockage is in an artery feeding the heart, or stroke if the artery feeds the brain. This is why LDL is called
'bad cholesterol and why you'll hear the words
lower lows and higher highs for LDL and HDL.
If your LDL cholesterol is above 160 mg/dL, you are at increased risk of heart disease. When diagnosed with atherosclerosis, your doctor will likely put you on a
low fat diet plan and possibly drugs to lower your LDL cholesterol below 100 mg/dL.
HDL
Roughly 30% of cholesterol is transported to cells by HDL. It's believed that HDL carries cholesterol away from the arteries back to the liver and then eliminated from the body so it may be that HDL removes excess cholesterol from plaques and slows their growth, which is why HDL known as "good" cholesterol. However, too little HDL (under 40 mg/dL for men; under 50 mg/dL for women) will put you at higher risk for heart disease or stroke.
Cholesterol and Diet
Your liver is the main producer of cholesterol and it produces all of the cholesterol your body needs. You can, however, get cholesterol through your diet. Animal based foods (egg yolks, meat, poultry, shellfish, milk (with fat) and other dairy products) contain it. Plant foods don't contain cholesterol since, frankly, they don't have a liver.
Trans fats and saturated fatty acids are the main cause of increased blood cholesterol in addition to dietary cholesterol. For example, the average American male eats about 330 mg of cholesterol each day (about 30% more than the liver is actually producing for its needs). While some of this excess cholesterol is removed by your liver, your should limit daily cholesterol as much as possible (less than 200 milligrams per day). MealMixer's
Healthy Diet Planner plans and tracks your fat and cholesterol for you so you can be proactive about the foods you buy and eat for managing a healthy heart.
Those with very high cholesterol might need substantially less dietary cholesterol. In this case, a vegetarian diet may be called for, also supported by the
Healthy Diet Planner.
Exercise, Smoking, Alcohol and Cholesterol
Regular
exercise can help control your weight, and increase the level of HDL in some people, which, again, is lowers your risk of heart disease. A sedentary lifestyle increases your risk of heart disease, but even moderate daily exercise (walking, gardening) can reduce your risk.
Smoking tobacco lowers HDL (as well increase your risk of cancer), so stop smoking if you are a smoker. Alcohol can increase HDL, so moderate consumption of alcohol (1-2 glasses of wine/day) may have a positive impact, so long as it is not abused in any way.