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Vitamins and Calcium Supplements (cont.)

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Folic Acid

What is folic acid, and what does it do?

Folic acid is the man-made form of folate, a naturally occurring B vitamin. Because it's a water-soluble vitamin, it cannot be stored in the body so it needs to be supplied on a continuous basis.

Folic acid helps form and maintain new cells. It is needed to make red blood cells and for the metabolism of homocysteine. It helps produce DNA, and it helps prevent changes in DNA that may lead to cancer.

How much do I need to consume?

The Recommended Dietary Allowances (RDA) for folate are expressed in a term called Dietary Folate Equivalent (DFE). The naturally occurring folate is absorbed differently than the man-made folic acid, so the DFE was developed to help account for these differences. One DFE is equal to 1 microgram (mcg) of food folate and 0.6 mcg of folic acid from supplements and fortified foods.

The RDA for folate:

Age Males and Females Pregnancy Lactation
1 to 3 years 150 mcg N/A N/A
4 to 8 years 200 mcg N/A N/A
9 to 13 years 300 mcg N/A N/A
14 to 18 years 400 mcg 600 mcg 500 mcg
19+ years 400 mcg 600 mcg 500 mcg

There is insufficient information to establish an RDA for folate for infants. In this case, an Adequate Intake (AI) has been established:

Age Males and Females
0 to 6 months 65 mcg
7 to 12 months 80 mcg

What are sources of folic acid?

Folate can be found naturally in many foods, including fruits, leafy green vegetables, and dried beans. Folic acid is added to certain foods because of regulations published by the Food and Drug Administration in 1996. These foods are considered enriched because the folic acid is replacing the folate that was lost during processing. Some common folic acid-enriched foods are cereals, breads, pasta, rice, flours, and cornmeal. Folic acid can also be added to foods and beverages in addition to the nutrients that they already contain. These foods are considered fortified with folic acid. In 1998, the folic acid fortification program was initiated to help Americans reach their folic acid recommendations.

Food sources of folate and folic acid are:

Food Amount Folate/Folic Acid Content
Asparagus, cooked 4 spears 85 mcg
Avocado, sliced, raw ½ cup 45 mcg
Banana, raw 1 medium 20 mcg
Beef liver 3 oz 185 mcg
Broccoli, chopped, frozen, cooked ½ cup 50 mcg
Broccoli, raw 2 spears 45 mcg
Cantaloupe, raw ¼ medium 25 mcg
Great Northern beans ½ cup 90 mcg
Green peas, frozen, cooked ½ cup 50 mcg
Papaya, raw, cubes ½ cup 25 mcg
Rice, white, enriched, cooked ½ cup 65 mcg
Spinach, frozen, cooked ½ cup 100 mcg
Spinach, raw 1 cup 60 mcg
Tomato juice 6 oz 35 mcg

Do I need to take a folic acid supplement?

The goal is to consume a balanced diet that provides your daily folate needs. The folate-enriched and -fortified foods make this much easier to accomplish. When you have a medical condition that interferes with the amount that you can consume, if you are unable to absorb all of what you consume, if your diet is limited, or if you have an increased need for folate, a supplement would be the best option. It is recommended that women who may become pregnant take 400 mcg of folic acid from fortified foods and/or dietary supplements along with consuming a well-balanced diet.

Another possible reason to take a supplement would be for heart protection. There are some studies that have shown that folic acid can lower homocysteine levels by up to 25%. High blood levels of homocysteine can damage the inner surface of blood vessels, promote blood clotting, accelerate atherosclerosis, and thus lead to heart attacks and strokes.

What happens if I don't have enough folic acid?

One very severe consequence of not getting enough folic acid is the possibility of neural tube defects during pregnancy. Neural tube defects usually develop in the first 28 days of pregnancy. Many women do not know that they are pregnant during this time and are not monitoring their folic acid intake. For this reason, it's a good idea to make sure that you have an adequate daily intake before trying to conceive.

A deficiency in folate can lead to megaloblastic (or macrocytic) anemia. It may also cause poor growth, gray hair, glossitis, mouth ulcers, diarrhea, and peptic ulcers. Studies have shown that low blood folate levels are associated with high blood homocysteine levels. High blood levels of homocysteine can damage the inner surface of blood vessels, promote blood clotting, accelerate atherosclerosis, and thus lead to heart attacks and strokes.

There are medical conditions and medications that can increase the need for folate, increase its excretion, or interfere with its utilization:

It's best to speak with your doctor if any of these applies to you.

Is there such a thing as too much folic acid?

There is no Tolerable Upper Limit (UL) set for natural sources of folate found in food.

There are UL set for folate from fortified foods and supplements.

Age Males and Females Pregnancy Lactation
1 to 3 years 300 mcg N/A N/A
4 to 8 years 400 mcg N/A N/A
9 to 13 years 600 mcg N/A N/A
14 to 18 years 800 mcg 800 mcg 800 mcg
19+ years 1,000 mcg 1,000 mcg 1,000 mcg

Going above the UL increases your risk for adverse health effects.

Next: Vitamin E


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