An emerging star among the B vitamins, the tiny molecule called folic acid, or folate, is showing immense promise. Folate has been the subject of intensive research efforts in the last decade. The research is so convincing that even the FDA, traditionally very conservative when it comes to making recommendations about vitamin supplements, is mandating that grain and cereal manufacturers add folate to several foods, beginning in January, 1998.
So what is all the buzz about? Since the 1940s, folic acid has been regarded as a valued nutrient. Science has known for a long time that folate, along with vitamin B12, is a key player in the formation of red blood cells. Extreme deficiencies of both B12 and folate can result in a rare type of anemia. But the new story about folate relates to its protective role in pregnancy, and in heart disease.
Folic Acid and the Heart
The heart is an amazing machine. Every day, it moves 1,000 gallons of blood through 60,000 miles of blood vessels. It must perform non-stop, 24-hours every day, seven days every week, throughout an average 73-year life span.
We have been hearing for years about how a low saturated fat diet, combined with aerobic exercise, can keep our hearts in shape. Now, we can add folic acid to the heart-health routine.
In 1995, the Journal of the American Medical Association published data showing reduced risk of heart disease for people who had good amounts of folic acid in the diet. The study forecast that over 15,000 fewer men and 12,000 fewer women in the United States would die of heart disease, if people consumed 400 micrograms of folic acid daily. That is micrograms, not milligrams. Four hundred micrograms is less than half a milligram. So a very small amount of folic acid may have a very large potential health benefit.
Little by little, researchers are uncovering information about how and why folic acid helps the heart and circulation. They have identified its role in the metabolism of a molecule known as homocysteine, a form of the amino acid cysteine. Homocysteine is formed during the breakdown of proteins, but normally it does not accumulate in the blood, and is converted to either regular cysteine, or another amino acid, methionine. Both cysteine and methionine are vital components for the synthesis of protein and other cellular operations.
Science has discovered that an accumulation of excess homocysteine seems to contribute to elevations in LDL cholesterol, and the build up of plaque that clogs arteries. Folic acid helps clear out the excess homocysteine, by enabling an enzyme to convert it to methionine. Studies indicate that folic acid works along with vitamin B12 to produce the conversions.
Some researchers maintain that elevated serum homocysteine is even more of a threat to heart health than LDL cholesterol. In an interview with the New York Times, Harvard physician Meir Stampfer indicated that homocysteine is in the same league as high cholesterol as a risk factor for heart disease and stroke.
The good news is that high levels of homocysteine are easier to treat than high levels of cholesterol. Studies show that folic acid, possibly in combination with B12 and B6, can do the job. South African research published in the Journal of Nutrition indicated that folic acid supplementation alone produced a 41.7% decrease in serum homocysteine, while folic acid taken with vitamins B6 and B12 reduced serum homocysteine levels by 49.8%.
Folic Acid and Birth Defects
Beginning in the late 1980s, evidence began to surface from European studies that folic acid reduces the risk of neural tube birth defects, including spina bifida, which results when the spinal cord fails to close during the early part of pregnancy.
Since that time, many studies have produced evidence to show that about half the incidence of neural tube defects could be prevented when the mother consumes adequate folate.
In 1992, the U.S. Public Health Service began recommending that all women of childbearing age consume 400 micrograms of folate daily, while pregnant and breast feeding women, should consume 800 micrograms per day.
The recommendation covers all women who can have children, not just those who are planning pregnancy. This is because over half of pregnancies are unplanned, and because these birth defects occur early in the life of the fetus, often before a woman even knows she is pregnant.
Folic Acid Food Fortification
Under the new FDA rule, food manufacturers must fortify enriched bread products, flour, corn grits, cornmeal, farina, rice, macaroni and noodles with .43 to 1.4 milligrams of folic acid per pound of product. Breakfast cereals can have up to 400 micrograms of folate per serving. All of this begins in January, 1998, although it may be some time later that we will begin to see folic acid listed in nutritional labels for some of these products. This is because the FDA is considering letting food manufacturers exhaust supplies of existing packaging before printing new labels that include folate content.
The levels of fortification adopted by the FDA are designed to keep daily folic acid intake below one milligram, because some research indicates amounts higher than that might mask symptoms in people afflicted with a B12 deficiency that causes a blood disorder known as pernicious anemia.
There are some scientists who maintain that much more prevention would occur if the fortification were 2.5 times higher than FDA-proposed levels. An analysis done by G. P. Oakley and colleagues at the Center for Disease Control in Atlanta estimates that fortification at higher levels would prevent about 1,000 spina bifida and similar birth defects each year and perhaps as many as 50,000 premature deaths each year from coronary disease. In a report published in the Journal of Nutrition last year, the CDC team reported that available data does not show any harm by increasing consumption of folic acid by 100 to 250 additional micrograms a day.
Meantime, you do not have to wait until January to start getting good amounts of folic acid in your diet. Many vitamin supplements contain folate. And there are rich animal and vegetable sources, including asparagus, oranges, beets, broccoli, chick peas, pinto beans, lentils, and other legumes. Folic acid is also in good supply in dairy products, tuna, and salmon.
Susan Moyers is a writer and educator focusing on health and science issues. She is the author of the popular book Garlic in Health, History, and World Cuisine. Florida 813-393-5986