500mg Of Vitamin C A Day Reduces LDL Cholesterol Levels

An orangeA study published this month in the Journal of Chiropractic Medicine has found that high doses of vitamin C can reduce an individuals LDL cholesterol levels and subsequently lower their risk of heart disease.

The research, conducted by Marc McRae of the National University of Health Sciences in Illinois, involved the analysis of results from 13 previous trials on the effect of vitamin C on cholesterol levels. The minimum dosage of vitamin C taken across the studies was 500mg/day for a period of between 3 and 24 weeks.

When the data from all the studies was pooled, vitamin C supplementation resulted in an average reduction of 7.9 mg/dL for LDL cholesterol levels while HDL cholesterol levels increased by 1.1 mg/dL. LDL cholesterol is the so called “bad” cholesterol because high LDL cholesterol levels are associated with an increased risk of heart disease. HDL cholesterol on the other hand appears to have preventative effects on heart disease.

The study also found that vitamin C reduced triglyceride levels in the blood by 20.1 mg/dL. High levels of triglycerides in the blood leads to atherosclerosis (the hardening of the arteries) and an increased risk of heart disease and strokes.

McRae added that the 7.9 mg/dL reduction in LDL cholesterol levels was equivalent to around a 6.6% reduction in coronary heart disease risk while the 20.1 mg/dL reduction in triglyceride levels corresponded to a 2.4% reduction in coronary heart disease risk.

While the minimum dosage of 500 mg per day is quite high and would be difficult to achieve through diet alone, most vitamin C supplements contain at least this amount. Vitamin C is also well tolerated in the body and no short or long term adverse effects have been observed from the use of vitamin C supplements.

It is believed that vitamin C reduces LDL levels by increasing the ability of the liver to transform cholesterol into bile acids. Vitamin C may also reduce the oxidation of LDL cholesterol and increase the number of LDL-receptors thus increasing the rate of removal of LDL cholesterol from the blood.

A desirable LDL cholesterol level is less than 100mg/dL while a desirable HDL cholesterol level is greater than 60mg/dL. Triglyceride levels lower than 150mg/dL are considered optimal.

Good dietary sources of vitamin C include: red peppers (175mg per serve), broccoli (123mg), brussel sprouts (97mg), strawberries (82mg), oranges (70mg), kiwifruit (57mg), and grapefuit (47mg). It should be noted that boiling vegetables for a long period of time can lead to as much as an 80% reduction in vitamin C levels so where possible vegetables should be lightly steamed or consumed raw to maximize the amount of available vitamin C.