Triglycerides and lowering triglyceride levels
Good cholesterol, bad cholesterol, saturated fat, and unsaturated fat - sometimes it seems like you need a programme to keep track of all the fatty players in the story of heart disease.
In some ways, the molecules called triglycerides are the easiest to understand. Simply put, triglycerides are fat in the blood, and a high triglyceride level can increase the risk of heart disease. Just what your triglyceride levels mean and how much lowering triglycerides reduces heart disease risk is less clear.
What are triglycerides?
Triglycerides are the main form of fat in the body. When you think of fat developing and being stored in your hips or belly, you're thinking of triglycerides. Consider these things:
- The fat we eat exists in relatively huge molecules inside food. Triglycerides are the end product of digesting and breaking down these bulky fats.
- Any extra food we eat that's not used for activity right away - carbohydrates, fat, or protein - is also chemically converted into triglycerides.
- Triglycerides are then bundled together into globules. These are transported through the blood. Proteins (called lipoproteins) help transport these triglyceride blobs.
- The triglycerides are taken up by adipose (fat) cells, to be used for energy if food isn't available later- or during your next diet.
Triglycerides are measured using a common test called a lipid profile. It's the same blood test that checks "good" and "bad" cholesterol levels. Within the UK the NHS has now suggested people aged 40-74 have a vascular health check which will include a lipid profile.
Triglyceride levels are checked after an overnight fast. Fat from a meal or other parts of the meal that get converted into triglycerides can artificially raise the triglyceride levels on the test.
What are normal and high triglyceride levels?
The American Heart Association defines the following:
- Normal triglycerides means there are less than 1.69 mmol/l (millimoles per litre).
- Borderline high triglycerides = 1.7-2.25 mmol/l
- High triglycerides = 2.26-5.65 mmol/l.
- Very high triglycerides = higher than 5.65 mmol/l.
High triglyceride levels are a risk factor for heart disease. Experts disagree, though, on just how bad of an effect high triglyceride levels by themselves have on the heart.
Part of the dispute stems from the fact that high triglycerides have a tendency to "run with" other risk factors. High triglyceride levels often coexist with high total cholesterol and LDL ("bad cholesterol"), low HDL ("good cholesterol"), and diabetes.
Triglycerides may be an "enabler" of other heart disease risk factors. That is, high triglyceride levels could multiply the bad effects of high cholesterol, high blood pressure, and smoking.
Some research also suggests that high triglycerides are a more important risk factor for women than for men, although this is also disputed.
One point is clear, though: A healthy diet and exercise plan can lower triglyceride levels, improve cholesterol levels, and lower the risk of heart disease.