Table of Contents
Although there are several diets that will result in lowered LDL cholesterol, the National Cholesterol Education Program (NCEP) set forth guidelines for medical professionals to follow when instructing patients on a medical nutrition option for lowering cholesterol. Termed the TLC diet or the Therapeutic Lifestyle Changes Diet it emphasizes heart healthy lifestyle choices.
The Therapeutic Lifestyle Changes diet (TLC) is a cholesterol lowering diet that refers to a cholesterol-lowering treatment that lowers a person’s low-density lipoprotein (LDL) level and raises their high-density lipoprotein (HDL) level enough to reduce their risk of a heart attack or other chronic disease caused by hardening of the arteries.
- Less than 7% of the day’s total calories from saturated fat.
- 25-35% of the day’s total calories from fat.
- Less than 200 milligrams of dietary cholesterol a day.
(Illustration by GGS Information Services/Thomson Gale.)
- Limit sodium intake to 2400 milligrams or less per day.
- Just enough calories to achieve or maintain a healthy weight and reduce your blood cholesterol level.
The NCEP classifies blood cholesterol levels as:
- Total Cholesterol less than 200 mg/dL, desirable; 200-239 mg/dL borderline-high; 240 mg/dL and above high.
- HDL Cholesterol less than 40 mg/dL as a major heart disease risk factor; 60 mg/dL and above gives some protection against heart disease.
Cholesterol is a waxy substance found only in foods of animal origin such as poultry, beef, fish, eggs, and dairy products. Cholesterol can be made from the liver and thus is not needed in the diet for normal cellular processes. Cholesterol must be combined with fats, proteins, and lipoproteins, before it can be transported through the body within the blood. There are many different lipoproteins that vary in size, function and composition. One of which is low-density lipoprotein (LDL). Commonly referred to as the “bad” cholesterol, it composes relatively two-thirds of total circulating blood cholesterol. Because the LDL transports cholesterol through the bloodstream, in high levels, it is associated with plaque deposits on the walls of the arteries resulting in a higher risk for cardiovascular events. High-density lipoprotein (HDL) referred to as the “good” cholesterol, scavenges excess cholesterol from the blood and brings it back to the liver for excretion. Research! shows that higher levels of HDL levels are related to lower levels of certain cardiovascular events. Another class of lipoproteins, the very-low-density-lipoproteins (VLDL), is responsible for carrying triglycerides through the bloodstream.
Evidence is clear that the major dietary contributors to elevated cholesterol are saturated fat, trans fat, dietary cholesterol, and an imbalance in caloric intake and energy expenditure resulting in weight gain. In some cases elevated cholesterol may be due to an underlying medical condition or certain prescribed medications as listed below, but not limited to:
- Nephrotic syndrome
- Chronic liver disease
- Monoclonal gammopathy
- Cushing’s syndrome
- Oral contraceptive use
- Anorexia nervosa
- Acute intermittent porphyria
- Protease inhibitor use
Other factors known to influence a persons blood cholesterol level include:
- Heredity. Genetic factors play a large role in the amount of cholesterol in a person’s blood.
- Age.As a person ages, their cholesterol level tends to rise gradually.
- Sex. Men tend to have higher LDL and lower HDL than premenopausal women.
- Menopause. After menopause, estrogen levels fall and women’s LDL cholesterol levels tend to rise.
- Weight. As weight rises, so does cholesterol. Usually LDL levels rise as HDL levels lower.
- Smoking. Smoking can lower a persons HDL levels.
- Exercise. Regular exercise raises a persons HDL levels. As well as help in weight loss or maintenance.
- Alcohol. Studies suggest that no more than one drink for women and two drinks for males may help in raising HDL levels.
In November 1985, in order to standardize the medical approach to treating high cholesterol blood levels, The National Heart, Lung, and Blood Institute (NHLBI) launched the National Cholesterol Education Program (NCEP). The overall goal of the NCEP is to “reduce illness and death from coronary heart disease (CHD) in the United States by reducing the percent of Americans with high blood cholesterol”.
In their first approach, the NCEP designed the Step 1 and Step 2 diet to lowering cholesterol. Designed as an initial diet for people with high dietary cholesterol, the Step I diet restricted total fat to no more than 30% of total calories, saturated fat to no more than 10% of total calories, and cholesterol to less than 300 mg/day. If this approach did not result in a lowering of cholesterol or for people post-myocardial infraction or at high risk of one, the Step II diet goals were instituted. They recommended less than 7% of total calories for saturated fat and less than 200 mg/ day of cholesterol.
For the general population, the NCEP still recommends a diet following the Step 1 recommendations. However, in May of 2001, the NCEP issued the Third Report of the Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III [ATP III]) which recommended the new TLC dietary therapy for subgroups of people with specific medical conditions and risk factors listed below:
High LDL cholesterol or other lipid disorders, coronary heart disease or other cardiovascular disease diabetes mellitus, insulin resistance or metabolic syndrome.
Soon after the report was issued, health organizations such as The American Heart Association (AHA) began to accept and endorse these recommendations. Now a majority of organizations have incorporated the TLC diet into materials on dietary and lifestyle change for people with high blood cholesterol.
The three cornerstones of the TLC lifestyle modification diet are:
- Dietary Changes. Reduction of saturated fat, trans-fat, and cholesterol within the diet. Addition of plant stanols and sterols. Increased consumption of soluble fiber.
- Weight Management. Weight loss can help lower LDL and is especially important for those with a cluster of risk factors that includes high triglyceride and/or low HDL levels. For those with a large waist measurement (more than 40 inches for men and more than 35 inches for women) it is important to lose weight to decrease the risk for developing heart disease.
- Physical Activity. Regular physical activity, at least 30 minutes on most, if not all, days is recommended every day of the week. Physical activity can help raise HDL and lower LDL and is important for those with high triglyceride and/or low HDL levels who are overweight with a large waist measurement
The TLC eating plan is one that advises less than 7% of calories from saturated fat and less than 200 mg of dietary cholesterol per day. There should be no more than 25-35% or less of total daily calories coming from total fat intake. A limit of 2400 mg of day of sodium is recommended. The TLC diet recommends weight maintenance and avoidance of weight gain through caloric homeostasis. If LDL cholesterol is not lowered through reduction of saturated fat and cholesterol intakes, then it is suggested that the amount of soluble fiber in the diet be increased.
The TLC Program is adjusted using a set of four categories that are based on ones heart disease risk profile to set LDL goals and treatment steps. For a person who has heart disease or diabetes, they are considered a category I, carrying the highest risk. For persons free of those conditions, their needs are based upon their personal risk of having a heart attack in the next 10-years based upon the Framingham Heart Study. The higher a persons risk category, the more important it is for them to lower their LDL and control any other heart disease risk factors (including smoking and high blood pressure) they have.
The TLC diet is prescribed for people who need to reduce their risk for heart disease. The main goal in treating high cholesterol via the TLC program is to lower a persons LDL level. Research has proven that a lowering of LDL levels can prevent or decrease the risk of heart attacks and reduce deaths from heart disease in both men and women. The TLC program can decelerate, stop, or reverse the buildup of plaque. When followed, it can also lower the cholesterol content in unstable plaques, making them less likely to burst and cause a heart attack. For those who have already experienced a myocardial infraction, the diet can reduce the risk of another heart attack, possibly prolonging life.
Along with a qualified physician, making sure that qualified professionals who can assist with safe dietary and lifestyle changes should include registered dietitians, doctors, nurses, psychologists, and exercise physiologists.
According to the NCEP Guidelines, all adults 20 years of age and older should have their total cholesterol as well as HDL-cholesterol measured every five years.
Positive Risk factors for heart disease:
- Male greater than 45 years of age
- Female greater than 55 years of age
- Female with premature menopause without estrogen replacement
- Family history of premature coronary heart disease having definite myocardial infarction or sudden death before age 55 in father or other first-degree male relative, or mother before age 65 years of age
- Currently smoking or history of cigarette smoking
- Blood pressure greater than 140/90 mmHg or on antihypertensive medications
- HDL cholesterol less than 35 mg/dl
- LDL cholesterol greater than 130 mg/dl
- Diabetes Mellitus
Scores of research articles support a direct relationship between LDL cholesterol levels and the rate of coronary heart disease (CHD) in a person. Within-population studies such as the Framingham and MRFIT studies and between-population studies, most notably the Seven Countries study support this research as well. Studies on familial Hypercholesterolemia, a genetic disorder characterized by high levels of LDL cholesterol, have an exceedingly high rate of premature atherosclerosis. The majority of research from experimental animals, laboratory investigations, epidemiology, and genetic forms of hypercholesterolemia indicate that elevated low-density lipoprotein (LDL) cholesterol is a major cause of CHD. In addition, clinical trials demonstrate a reduction of coro
nary heart disease risk when low-density lipoprotein-lowering therapy is instituted. For these reasons, the NCEP Expert Panel on Detection, Evaluation, and Treatment of High Blood cholesterol in Adults (Adult Treatment Panel III) continues to identify elevated low-density lipoprotein cholesterol as the primary target of cholesterol-lowering therapy.
Hark, Lisa and Gail Morrison. Medical Nutrition & Disease: A Case-based Approach, 2003.
Marian, Mary J., Pamela Avonne Williams, and Jennifer Muir Bowers. Integrating Therapeutic and Complementary Nutrition , 2006.
Meskin, Mark S. et al. eds. Phytochemicals: Mechanisms of Action 2003.
Stamford, Bryant A. and Robert J. Moffrat. Lipid Metabolism and Health 2006
Stanfield, Peggy S. and Yiu H. Hui. Nutrition and Diet Therapy, 2003.
National Cholesterol Education Program NHLBI Information Center. P.O. Box 30105 Bethesda, MD 20824-0105 <http://www.nhlbi.nih.gov>.
National Diabetes Information Clearinghouse http://diabetes.niddk.nih.gov/
Tobacco Information and Prevention Source TIPS. <http://www.cdc.gov/tobacco/index.htm>.
Megan C.M. Porter, RD, LD