High cholesterol and coronary heart disease
Part 4: Dietary cholesterol doesn't affect blood cholesterol
Dietary cholesterol was also was ruled out as a cause of raised blood cholesterol and heart disease.
The longest running and most respected is the Framingham Heart Study. This study was set up in the town of Framingham, Massachusetts, in 1948 and is still going on today. It was this study that gave rise to other 'risk factors' with which we all are so familiar today: lack of exercise, smoking, and so on.
The Framingham researchers thought that they knew exactly why some people had more cholesterol in their blood than others — they ate more in their diet. To prove the link, they measured cholesterol intake and compared it with blood cholesterol. As the Table shows, although subjects consumed cholesterol over a wide range, there was little or no difference in the levels of cholesterol in their blood and, thus, no relationship between the amount of cholesterol eaten and levels of blood cholesterol was found.
| Table I: Cholesterol intake — The Framingham Heart Study | |||
| Blood Cholesterol in Those | |||
| Cholesterol Intake |
Below Median Intake |
Above Median Intake |
|
|
mg/day
|
mmol/l (mg/dL)
|
mmol/l (mg/dL)
|
|
| Men |
704 +/- 220.9
|
6.16 (237)
|
6.16 (237)
|
| Women |
492 +/- 170.0
|
6.37 (245)
|
6.26 (241)
|
Next, the scientists studied intakes of saturated fats but again found no relation; there was still no relation when they studied total calorie intake. The researchers then considered the possibility that something was masking the effects of diet, but no other factor made the slightest difference. After 22 years of research, the researchers concluded:
'There is, in short, no suggestion of any relation between diet and the subsequent development of CHD in the study group.'[1]
That was in 1970, and no finding since has changed that view.
There is not now, and never has been, any evidence that either total blood cholesterol or the intakes of dietary cholesterol increases the risk of a heart attack.
Reference
1. Kannel WB, Gordon T. The Framingham Diet Study: diet and the regulations of serum cholesterol (Sect 24). Washington DC, Dept of Health, Education and Welfare, 1970.
