Ideally, your total cholesterol should be below 150 mg/dL. According to William Castelli, who was the medical director of the Framingham Heart Study for many years, people with a total cholesterol value of less than 150 mg/dL simply don’t get heart attacks. And once someone’s total cholesterol is that low, the ratio between the “good” and “bad” cholesterol simply doesn’t matter.
The total cholesterol value is the single most important clue to a person’s risk of heart attack. Once the cholesterol levels in the blood rise to, say, the mid-160s, then the ratio of good versus bad cholesterol (HDL versus LDL) really starts to matter.
William Castelli once explained, “Four out of five people on this earth can’t get their cholesterol over 150; they don’t get heart attacks. One out of five people can’t get their cholesterol down to 150. They do get heart attacks. And almost all of them live in affluent countries.” The “four out of five people” Castelli meant live in societies that eat a low-fat, high-fiber, largely plant-based diet. That kind of diet keeps blood cholesterol levels naturally low.
To see how cholesterol values relate to the risk of heart attack, look at the graphs on this page: http://heartriskonline.com/CholesterolChart.htm