Coronary heart disease is responsible for 650,000 deaths each year in the United States alone and is the leading cause of death in men and women alike. Several risk factors for this disease have been identified including obesity, sedentary lifestyles, smoking, diabetes and an abnormal lipid profile, that is, high total cholesterol, elevated low-density (LDL) cholesterol and low levels of high-density lipoprotein (HDL) cholesterol.
Cholesterol is essential to the proper function of the human body. Cholesterol travels in the circulation and is present in every cell in the body. Sunlight-generated cholesterol is used to form cell membranes and is a precursor to vitamin D and certain hormones such as estrogen and testosterone. Cholesterol also aids in bile formation which helps to digest dietary fats. Finally, cholesterol helps to maintain myelin, which acts as an insulating layer around nerves.
About 75% of cholesterol in the blood is produced in the body (primarily the liver) and 25% comes from the diet. There is an ideal range of circulating cholesterol for the body to function most efficiently. Too little cholesterol and too much cholesterol each carry certain risks. Too little cholesterol in the circulation has been linked to depression and anxiety, possibly caused by reduced serotonin levels. Also, low total cholesterol is often linked to low HDL levels, which increases heart disease risk. However, there is no definitive evidence that low cholesterol levels negatively affect health. On the other hand, there is an abundance of research that shows that elevated total cholesterol levels (200 mg/dl)* increases the risk for chronic disease including heart disease and cancer.
The major classifications of cholesterol include HDLs and LDLs. High-density lipoproteins, or good cholesterol, carries about one-third of the total cholesterol in the circulation. HDL carries cholesterol from the arteries to the liver where it is excreted from the body. High HDL levels (60 mg/dl)* are protective against heart disease whereas low HDL levels (40 mg/dl)* increases this risk. Bad cholesterol or low-density lipoproteins, carries the remaining two-thirds of the total cholesterol in the circulation. Excess LDL levels can lead to plaque buildup in the arteries near the brain and heart and increases stroke and heart attack risk. In high-risk patients, LDL should be 100 mg/dl*, since these levels have been shown to reduce mortality and cardiovascular morbidity, medium-risk and low-risk patients should maintain LDL below 130 and 160 mg/dl*, respectively.
Cholesterol levels are an important risk factor for heart disease in adults and recent efforts have emphasized the need for regular cholesterol monitoring in some children. With the recent epidemic of childhood obesity, children and teenagers are developing high cholesterol and heart disease. High cholesterol in childhood is also recognized as a significant predictor of cardiac disease in adulthood. In order to address this problem, the American Academy of Pediatrics developed guidelines in summer 2008 for monitoring and treating children with high cholesterol levels. Children with a family history of elevated cholesterol, high triglycerides, or early cardiovascular disease and children who are overweight, diabetic or hypertensive should have a lipid profile test at age 2 and every 3-5 years thereafter.
Blood cholesterol levels are affected by genetics to a certain degree but are mostly related to lifestyle choices, especially diet. While many may rely on bottled nutritional approaches such as whole food supplements or vitamin tablets, a proper diet supersedes all. Eating animal products, like meat and eggs regularly can increase total and LDL cholesterol because of its high concentration of saturated fat and cholesterol. Substituting animal products with foods that contain polyunsaturated and monounsaturated fats can lower total and LDL cholesterol and raise HDLs. Polyunsaturated fats are most commonly found in sesame, safflower, soybean, sunflower oils and in fatty fish like salmon, mackerel and albacore tuna. As with polyunsaturated fats, substituting saturated fat intake for monounsaturated fats improves the lipid profile with lower total, lower LDL and higher HDL. Foods with high levels of monounsaturated fats include olive, peanut and canola oil.
Foods that contain soluble fiber can also improve lipid profiles (please get tested for food intolerances). Oatmeal, oat bran, all beans and apples contain high levels of soluble fiber and have been shown to lower total and LDL cholesterol by reducing cholesterol absorption in the intestine. The recommended soluble fiber intake to attain these health benefits is 10 grams or more each day. A diet that is abundant in plant nutrients rich foods will also help lower cholesterol levels.
Aside from diet, regular aerobic exercise also improves the lipid profile (good), primarily by increasing HDL levels an average of 2.5 mg/dl*. Since cardiac disease risk drops by 2-3% for every 1 mg/dl* increase in HDL, regular aerobic exercise can reduce this risk by 5-8%. These benefits are attained with only 20 minutes of exercise each day. For every 10 minutes extra each day, cardiac risk drops by 3-4%. Therefore, increasing the duration of exercise sessions is one of the best ways to improve lipid profiles. Finally, obesity and tobacco use have a negative impact on the lipid profile and should be avoided.
Overall, the best ways to maintain healthy cholesterol levels are to maintain a healthy body weight, avoid tobacco, exercise regularly and substitute animal products with foods containing mono- and polyunsaturated fats. Fat should contribute no more than 30% of daily calorie intake and saturated fat intake should contribute no more than 7% of daily calories. For example, if a person is on a 2000 calorie per day diet, no more than 600 calories (or about 67 grams) should come from fat and no more than 140 calories (or about 16 grams) should come from saturated fat. Dietary cholesterol should be limited to 300 milligrams per day, although 200 milligrams is the safe upper limit for those at risk for heart disease. Although most research suggests that dietary cholesterol in itself does not increase blood cholesterol by large amounts, foods that contain cholesterol usually contain saturated fats as well and have the greatest impact on cholesterol levels. By following these recommendations, lipid profiles can respond rapidly, often with 4-6 weeks. Maintaining a healthy lipid profile will lower the risk of heart and other chronic diseases.
* mg.--milligrams. dl. --deciliters
200mg/dl = 9.9mg. per teaspoon
60mg/dl = 2.96mg. per teaspoon
40mg/dl = 1.97mg. per teaspoon
100mg/dl = 4.93mg. per teaspoon
160 mg/dl = 7.89mg. per teaspoon
2.5mg/dl = 12 mg. per teaspoon
1mg/dl = 0.5mg. per teaspoon