Understanding the Cholesterol Ratio
You certainly know about the total cholesterol and that a level below 200 mg/dL is the ideal. But, did you know that your level can be above 200 and have no impact on your health? The total cholesterol number itself alone does not say much. You may have a cholesterol level of 200 mg / dL because you have a lot of “good” HDL (high-density lipoproteins) cholesterol or a lot of “bad” LDL (low-density lipoproteins) cholesterol. What is much more important to know is your cholesterol ratio.
What is it?
The cholesterol ratio, known as Castelli index or atherogenic index is the number obtained by dividing your total cholesterol level by your HDL level.
Cholesterol ratio = Total cholesterol / HDL
If you have a total cholesterol value of 220 mg/dL and an HDL of 65 mg/dL, your ratio is 3.38.
The less HDL cholesterol your blood contains, the higher is the ratio and vice versa: the higher your HDL, the smaller the quotient.
This relationship shows whether the levels of HDL or good cholesterol are sufficient to “handle” the total cholesterol load and directly indicates the concentration of LDL and VLDL (very low-density lipoproteins. This is useful when HDL appears to be adequate but total cholesterol is very high.
What influence does the Total Cholesterol / HDL ratio have on your health?
The relationship between total cholesterol and HDL provides indications of the risk of getting a cardiovascular disease (eg atherosclerosis, heart attack, stroke, etc.). The higher the value, the higher the disease probability. That’s because your blood contains a significant amount of more LDL and VLDL (both responsible of harmful effects on the blood vessels and the heart) in relation to HDL, the “good” cholesterol, which role is to clean the blood vessels. On the other hand, the lower the ratio, the more HDL your blood contains and the better you are protected from cardiovascular disease.
What is the normal range?
Different studies have shown that women have higher HDL levels than men but with the same risk. Therefore, the ratio of total cholesterol / HDL cholesterol desirable for women is lower.
The chart below shows the healthy and bad ranges with the risk of coronary heart disease (CHD) associated with the Castelli index.
Cholesterol ratio chart for men and women
|<3.5||<3.4||Half the average|
|3.5 - 5.0||3.4 - 4.5||Average|
|5.1 - 9.6||4.5 - 7.1||Twice the average|
|9.7 - 24||7.2 - 11||Three times the average|
In healthy adults without risk factors, a ratio up to 3.5 and 3.4 is considered okay respectively for men and for women. Values over 5 for men and 4.5 for women are problematic. The risk of cardiovascular disease is then significantly increased. If your ratio is in these ranges, you should improve take actions to improve it quickly. With a quotient of 4.4, your risk of CHD would be just as high as that of the average population. With a ratio of 3.3, your risk is only half that of the average population.
What to do when your ratio is high
Take this as an opportunity to do more immediately for your health. Increase your HDL level and get your LDL level down! You can achieve this through proper nutrition and physical exercise!
Overall, your diet should be low in fat and characterized by “heart-protecting” types of fat (those with mono- and polyunsaturated fatty acids). Recommended is, for example, cooking with extra virgin olive oil and avocado oil, and the restriction of meat consumption in favor of fish or vegetable products.
Physical exercise improves your fat metabolism in two ways: Firstly, it increases your calorie consumption and thus the fat burning in your body, and secondly increases the HDL level in your blood. It is important that you move several times a week and for more than half an hour.