Cholesterol Ratio (Total/HDL)
Calculate the total cholesterol to HDL ratio, an indicator of cardiovascular risk. Below 3.5 is ideal; above 5 points to high risk for your heart.
CT/HDL + risco
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Total cholesterol / HDL ratio
The TC/HDL ratio divides total cholesterol by HDL: ratio = TC / HDL. Plug in TC = 200 mg/dL and HDL = 50 mg/dL and you get a ratio of 4.0. How to read it: < 3.5 ideal, 3.5–5.0 intermediate, > 5.0 elevated cardiovascular risk. For a long time it was treated as a sharper predictor of coronary events than total cholesterol on its own, and the Framingham Heart Study leaned on it a lot. These days the AHA tends to favor LDL-C along with broader tools like the ASCVD risk score. One number worth tracking alongside it is non-HDL cholesterol (TC − HDL), since it captures all the atherogenic lipoproteins at once: LDL, VLDL, IDL, Lp(a).
Applications
You will see it in cardiovascular screening, hospital admission panels and routine lab reports. It also shows up when deciding whether to start a statin (read together with the ASCVD score) and when following someone with dyslipidemia over time. Patients tend to find it easy to follow, since it folds two numbers into a single value they can watch.
FAQ
Is the ratio better than LDL? It holds up well as a predictor, but current guidelines put the weight on LDL-C and non-HDL together with global risk (ASCVD). Treat the ratio as something that rounds out the picture rather than stands in for the rest.
What if HDL is very high? A very high HDL (> 80 mg/dL) pulls the ratio down by arithmetic alone, but that does not always mean lower risk. At those extremes the HDL can be dysfunctional.
Fasting required? Current guidelines no longer insist on fasting for total cholesterol and HDL. Triglycerides and calculated LDL are a different story, and 9–12h fasting is still the usual advice there.
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The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.