Fiber is not without adverse effects, however, such as interfering with the absorption of certain minerals and vitamins. In general, foods rich in phytochemicals and vitamins are also rich in fiber. There are data to justify supplementation with vitamin E, vitamin C, folic acid, and Ca but less convincing data to support the use of vitamin B 6 and B 12 . Vitamin E decreases the oxidation of serum LDL-C and thus appears to reduce its capability for vascular damage. A recent study among nurses showed that diets higher in vitamin E were associated with lower death rates from heart disease but failed to show a specific benefit of vitamin E supplementation, possibly because of problems with study design and data collection.
Further studies are underway.
Vitamins B 6 and B 12 also lower homocysteine levels, but evidence justifying their use in general prevention is scanty. Calcium 500 mg bid, aside from its other benefits, appears to have a role in normalizing BP in certain persons. However, there have been no controlled trials on the optimal intensity, duration, frequency, or type of exercise. Also, the question of whether people with healthy hearts choose more active lifestyles or whether active lifestyles lead to healthier hearts remains unanswered. Several controlled but small studies demonstrated beneficial effects of exercise on BP and on CAD risk.