Folic Folate

Dec 18, 2008 9:31 PM

see Harvard Heart Health Dec 2008 "Folic acid:  Too much of a good thing?

I have pdf in med files.

Summary:  take only 400 mics per day NOT 800  (more may block absorption of folate).

Total limit set by Inst of Med is 1000 mics per day from supplements.

Some concern that high doses may promote cancer by blocking the entry of folate into cells.

One trial also showed increased coagul of stents post angio.

Folate is a B vitamin found in beans,

various greens, sunfl ower seeds, and

many other fruits and vegetables. It

plays a key role in health by helping

make, protect, and repair DNA, the

double helix that carries the body’s operating

manual. It also helps the body

convert some amino acids (the building

blocks of proteins) into others.

Folic acid is a synthetic form of folate

that is added to food or used as an

ingredient in vitamin supplements. Th e

body absorbs folic acid faster than it

absorbs folate. But folic acid must then

be converted into folate before it can

get to work.

Th e two latest trials show little heart

benefi t. In a trial in Norway, taking 800

micrograms (mcg) of folic acid daily for

three years lowered homocysteine by

30% in 3,000 people with coronary artery

disease. But it had no eff ect on the

number of heart attacks or deaths from

heart disease (Journal of the American

Medical Association, Aug. 20, 2008). A

similar pattern emerged from the Women’s

Antioxidant and Folic Acid Cardiovascular

Study, which lasted for seven

years (Journal of the American Medical

Association, May 7, 2008).

The early hope—and some

hype—for folic acid hasn’t yet

been toned down by the reality

of the results. Many people

take extra folic acid “just

in case.” But those taking a lot

of it may be getting more than

they bargained for.

Most adults should get a total

of 400 mcg of folate or folic

acid a day. (Women who are

pregnant should get 600 mcg;

those who are breast feeding,

500 mcg.) Th e Institute of

Medicine has also set a “tolerable

upper limit” of 1,000 mcg

per day of folic acid from fortifi

ed foods or supplements;

Studies going back many years have

linked a diet low in folate, which translates

into little folate available for cells,

to the growth and development of early

tumors. Several recent studies suggest

that getting a lot of folic acid might

promote colorectal, breast, and prostate

prostate

cancers by keeping folate out of

cells. A few small studies of memory

show a similar pattern—plenty of folate

is good, but a lot of folic acid may not

be. In the heart realm, one trial showed

that taking high doses of folic acid after

angioplasty increased the chances

of having the artery clog up again, the

opposite of what the researchers had

anticipated. Th ese are preliminary fi ndings.

But together they sound a warning

about getting too much folic acid.

Many people get more folic acid than

folate each day. It’s hard not to, and up

to a point it doesn’t matter. Th e problem

is that some foods, especially breakfast

cereals, deliver nearly a day’s worth

of folic acid. Add that to what you get

from eating other fortifi ed foods and

taking a multivitamin, and you could

easily break through the Institute of

Medicine’s safe ceiling. Eating a bowl

of Special K (394 mcg) for breakfast,

pretzels (172 mcg) for a snack, a cup of

cooked spaghetti (166 mcg) for dinner,

and a multivitamin (400 mcg) gives

you more than 1,100 mcg of folic acid.

• Our bodies need folate, a B vitamin

found in fruits, vegetables, and seeds,

for several important tasks.

• Synthetic folic acid, which our bodies

convert to folate, is added to grains

and other foods.

• Getting too much folic acid may block

the action of folate. If you take a multivitamin,

avoid foods fortifi ed with more

than 300 mcg of folic acid.

Some nutrition watchers are saying

we should stop taking daily multivitamins

so we don’t get too much folic

acid. Others suggest taking a multivitamin

every other day to limit folic

acid intake. Here’s a better option as

scientists sort out the real meaning of

high doses of folic acid: take a multivitamin-

multimineral supplement every

day, but avoid foods fortifi ed with

nearly a day’s worth (300–400 mcg) of

folic acid. Th at way you are sure to get

enough folic acid even if you don’t eat

breakfast cereal or other grains. You’ll

also get other B vitamins to balance folic

acid, along with a host of vitamins

and minerals you may not be getting

in your diet.