Dietary Fat and Cholesterol: What You Need to Know

A reader wants to know: What is the relationship between fat and good and bad cholesterol? Here’s what Dr. Zachary Levine has to say.


Q: What is the relationship between fat and good and bad cholesterol?

A: Dr. Zachary Levine:  The relationship between dietary fat and cholesterol is this – too much saturated fat (bad fat) is associated with increased levels of bad cholesterol (LDL). Having higher cholesterol levels is a risk factor for cardiovascular disease. Cholesterol is an organic substance (a waxy steroid of fat) that is essential to our cell membranes, bile and steroid hormones. Much of it is made in the liver, and some comes from our diet, primarily from animal products. You should have your blood cholesterol level measured if you are a man 40 or older, a woman 50 or older, are diabetic, have high blood pressure, smoke, are obese or have a family history of heart disease at less than 60 years old.

When you have your cholesterol checked, you should not eat for 12 hours beforehand. The blood test measures the levels of LDL and triglycerides, considered bad cholesterol because higher levels of them are associated with higher risk of cardiovascular disease. It also measures the level of HDL, considered good cholesterol because it seems to be protective against cardiovascular disease. By looking at factors including your age, gender, blood pressure, smoking, diet and diabetes, your doctor can determine what cholesterol level you should be aiming for.

If you need to lower your cholesterol levels, there are several methods: smoking cessation, improved diet, weight reduction and maintenance, and regular exercise. If these don’t work, there are numerous medications currently available, including statins, bile acid and/or cholesterol absorption inhibitors, fibrates and niacin. Your doctor and you can decide the best strategy for you.