What is the Cholesterol Ratio?
The cholesterol ratio (also called the atherogenic index) is calculated by dividing your total cholesterol by your HDL cholesterol:
Cholesterol Ratio = Total Cholesterol ÷ HDL
This ratio gives a quick snapshot of the balance between your total cholesterol and protective HDL cholesterol. A lower ratio is better.
Cholesterol Ratio Ranges
| Ratio | Risk Level |
|---|---|
| Less than 3.5 | Optimal — Low cardiovascular risk |
| 3.5 - 5.0 | Acceptable — Average risk |
| 5.0 - 6.0 | Borderline — Above average risk |
| Greater than 6.0 | High — Increased cardiovascular risk |
Why the Ratio Matters
Looking at total cholesterol alone can be misleading. Someone with high total cholesterol but also high HDL may have a better risk profile than someone with lower total cholesterol but very low HDL.
The ratio captures this relationship. It's a simple way to assess whether you have enough protective HDL to balance your total cholesterol.
How to Improve Your Ratio
You can improve your cholesterol ratio by either lowering total cholesterol, raising HDL, or both:
- Exercise regularly — One of the most effective ways to raise HDL
- Quit smoking — Smoking lowers HDL significantly
- Reduce saturated fat — Lowers total and LDL cholesterol
- Eat healthy fats — Olive oil, nuts, and fatty fish can raise HDL
- Maintain healthy weight — Weight loss improves both numbers
- Limit alcohol — Moderate consumption may raise HDL, but excess is harmful