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The cholesterol/HDL ratio is your total cholesterol divided by your HDL cholesterol. A high ratio may point to a higher risk of a disease of the heart and blood vessels.[1]
On this page you can read what the cholesterol/HDL ratio is, what the guidelines say about a value that is too low or too high, what affects your value and which values are best to look at alongside it.
Also known as: total/HDL cholesterol ratio, TC/HDL ratio, an atherogenic index. At the lab: n/a.
The cholesterol/HDL ratio is a ratio. Your total cholesterol is divided by your HDL cholesterol. So it is not a separate measurement, but a calculation using two values from your blood.[1]
A ratio like this is also called an atherogenic index. It was devised to get more out of your lipid profile than a single value does.[1]
For a long time, LDL cholesterol was the main measure of the risk of a disease of the heart and blood vessels. Ratios between fat values were devised to predict that risk better.[1]
According to the review, the total/HDL ratio and the LDL/HDL ratio predict the risk better than separate values on their own, and especially better than LDL alone.[1]
The authors believe future guidelines should take these ratios into account. In particular, the ratios that include HDL cholesterol.[1]
| Level | Can point to | Who it is for |
|---|---|---|
| Ratio above the risk cut-off[1] | a higher risk of a disease of the heart and blood vessels | people whose risk the doctor is assessing |
| Ratio that includes HDL cholesterol[1] | a better prediction of that risk than separate values, especially better than LDL alone | the doctor's everyday practice |
Source: Millán et al., a review of ratios between fat values in the blood and the risk of a disease of the heart and blood vessels.[1]
A ratio above the risk cut-off may point to a higher risk of a disease of the heart and blood vessels. Your doctor looks at the ratio together with your other values.[1]
BioProfile is working on its own zones for each value, from risk to optimal. A doctor reviews those zones before they appear in your result.
The ratio divides your total cholesterol by your HDL cholesterol. If your total cholesterol goes up while your HDL stays the same, the ratio rises.[1]
HDL cholesterol is the bottom part of the ratio. If your HDL falls, the ratio rises. If your HDL rises, the ratio falls.[1]
The review also mentions the ratio as a target for medicines that lower the fats in your blood. Whether that applies to you is something to discuss with your doctor.[1]
Cholesterol/HDL ratio is included in BioProfile 77, 87, 121 and 150.[2]
The BioProfile editorial team wrote this page on 10 October 2026 from the sources below, which we read on 10 October 2026. Every number on this page appears in one of those sources, with that source's number next to it. An expert has yet to check this page; after that check, the expert's name and the date of the check will appear at the top. This page offers explanation, not a diagnosis. Discuss a value outside the range with your GP.
