School of Public Health/Brigham and Women’s Hospital, in Boston, demonstrated that a diet
providing more than 400 mcg folate and 3 mg vitamin B 6 daily, either from food or supple-
ments, might reduce a woman’s risk of heart attack by almost 50 percent. Although men
were not included in the study, the results were assumed to apply to them as well.
However, data from a meta-analysis published in the Journal of the American Medical
Association in December 2006 called this theory into question. Researchers at Tulane Univer-
sity examined the results of 12 controlled studies in which 16,958 patients with preexisting
cardiovascular diseases were given either folic acid supplements or placebos (“look-alike”
pills with no folic acid) for at least six months. The scientists, who found no reduction in the
risk of further heart disease or overall death rates among those taking folic acid, concluded
that further studies will be required to verify whether taking folic acid supplements reduces
the risk of cardiovascular disease.
Adverse Effects Associated with This Food
Pigmented urine and feces. The ability to metabolize betacyanins and be taxanthins is a
genetic trait. People with two recessive genes for this trait cannot break down these red pig-
ments, which will be excreted, bright red, in urine. Eating beets can also turn feces red, but
it will not cause a false-positive result in a test for occult blood in the stool.
Nitrosamine formation. Beets, celery, eggplant, lettuce, radishes, spinach, and collard and
turnip greens contain nitrates that convert naturally into nitrites in your stomach—where
some of the nitrites combine with amines to form nitrosamines, some of which are known
carcinogens. This natural chemical reaction presents no known problems for a healthy adult.
However, when these vegetables are cooked and left standing for a while at room tempera-
ture, microorganisms that convert nitrates to nitrites begin to multiply, and the amount of
nitrites in the food rises. The resulting higher-nitrite foods may be dangerous for infants
(see spinach).
Food/Drug Interactions
Beets