Total cholesterol levels are the sum of all types of cholesterol in the blood. The higher the total cholesterol level, the greater the risk for heart disease. A total cholesterol level of under 200 mg/dL (5.18 mmol/L) is desirable.

Triglycerides are a form of fat that the body uses to store energy. Elevated triglycerides can be due to physical inactivity, cigarette smoking, excess alcohol consumption, being overweight/obese, and a diet very high in carbohydrates. Triglyceride levels of less than 150 mg/dL (1.70 mmol/L) are desirable.

HDL cholesterol is known as “good” cholesterol because high levels of HDL can protect against heart attack. Medical experts believe that HDL carries cholesterol away from the arteries and removes excess cholesterol from arterial plaque, slowing its buildup. For HDL cholesterol, higher levels are better. An HDL level above 60 mg/dL (1.55 mmol/L) is desirable.

When LDL (“bad”) cholesterol circulates in the blood, it can slowly build up in the inner walls of the arteries that feed the heart and brain. This “plaque” is a thick, hard deposit that can narrow the arteries and make them less flexible. Heart attack or stroke can result if a clot forms or an artery is blocked. An LDL cholesterol level below 100 mg/dL (2.59 mmol/L) is optimal. A high LDL cholesterol level dramatically increases the chances of developing heart disease or having a heart attack, making LDL a very important number to track. LDL levels can be calculated using the following formula: