Lipoproteins consist of proteins combined with fat, cholesterol and triglycerides. They are what is measured when you get a cholesterol test, also known as a lipid profile. Stored lipids are an energy source for the body. They are necessary for health, but adverse effects on the cardiovascular system occur when blood levels are too high, or in the case of high-density lipoprotein, too low.
Triglycerides
The body converts fat and carbohydrates into triglycerides for storage. When you need energy between meals, hormones cause triglycerides to be released. Based on size and density, five types of lipoproteins exist. Three of the five carry triglycerides and can be measured in a lipid profile. A high blood level of triglycerides is associated with coronary artery disease and may be related to untreated diabetes mellitus, according to the American Heart Association. A desirable level is below 150mg/dL. Borderline high is 150 to 199mg/dL, high is 200 to 499mg/dL, and very high is above 500mg/dL.
HDL
High-density lipoprotein, or HDL, is the smallest and most dense lipoprotein. It is commonly called the "good" cholesterol, because it helps prevent another lipoprotein, LDL or the "bad" cholesterol, from being oxidized and damaging artery walls. HDL removes cholesterol from artery walls, returning it to the liver for disposal. It has antioxidant properties and may fight inflammation. HDL is the only one of the five lipoproteins for which a high level is desirable. It should be at least above 40mg/dL, but preferably above 60mg/dL.
Metabolic Syndrome
Metabolic syndrome is associated with atherosclerotic cardiovascular disease, which occurs when arteries narrow and stiffen due to deposits of fat and cholesterol on the walls, resulting in heart attack or stroke. Metabolic syndrome is a cluster of factors, two of which are high triglycerides and low HDL. Other factors are excess abdominal fat, high blood pressure and a fasting glucose above 110mg/dL, indicating a link between lipid levels and diabetes.
Interaction
High triglycerides are associated with blood clots and inflammation. When HDL levels fall, triglycerides rise. For this reason, high HDL is considered protective for the heart. The American Heart Association advises that, for some people, consuming excess carbohydrates lowers HDL and increases triglycerides. Carbohydrate intake is also a factor in diabetes control, indicating another link between lipid levels and diabetes.
Treatment
To lower triglycerides and raise HDL, lose excess weight by eating fewer calories and more fruit and vegetables, and by reducing consumption of saturated fat, trans fat and cholesterol. In addition, the American Heart Association advises reducing alcohol consumption and getting at least 30 minutes of moderately intense exercise each day. Omega-3 fatty acids have also been shown to reduce triglycerides and raise HDL. They are found in fatty fish, such as salmon, herring, mackerel and sardines.
