Folate, also known as tetrahydrofolate and vitamin B9, is a water-soluble vitamin. The name folate comes from nature’s largest source of this essential vitamin, foliage such as leafy green vegetables.
Many people consuming the Standard American Diet (SAD) and a traditional Costa Rican diet are found to be deficient in folate, while most of those eating a plant based diet haver higher levels of most nutrients, including folate.
It is essential for DNA and RNA synthesis, amino acid metabolism and erythropoiesis (red blood cell production) and the metabolism of homocysteine, which I discuss in another article: Methionine and Homocysteine.
Long-term increases of dietary folate have been associated with reductions in the risk of stroke and cardiovascular disease, while low levels of folate have been associated with major depression and anxiety disorders, poor mental health, and insomnia. High levels of folate have been proven to improve mental health by three fold. I emphasize that this is referring to dietary folate, not supplemented folic acid.
FOLATE VS FOLIC ACID
Folate is a naturally occurring essential vitamin, while folic acid is the oxidized synthetic compound found in supplements and fortified foods. Folic acid is used when being added to food because it has a longer shelf life and stability and for some reason has grown to be synonymous by the public with folate, which it is not.
Folate is easily absorbed and metabolized in the small intestines, but folic acid needs enzymes such as dihydrofolate reductase (DHFR) and methylenetetrhydrafolate reductase (MTHFR) to be able to be utilized by the body.
Individuals who have a mutation of the MTHFR gene who have a decreased production (of up to 70%) of the MTHFR enzyme, while high folic acid intake actually inhibits the DHFR enzyme and can block natural folate absorption. Both of these factors make it so that unmetabolized folic acid levels in the blood rise and can cause hormone imbalances, immune dysfunction, cognitive decline, trouble concentrating, insomnia, mood changes, epilepsy, B12 deficiency.
High serum folic acid has also been associated with precancerous cell formation and increased risk of developing malignant tumors. This is one of the many reasons that I recommend avoiding foods, especially grains, that are fortified with folic acid and multivitamins that have folic acid instead of 5-methyltetrahydrofolate.
RECOMMENDED DAILY ALLOWANCE
The daily folate requirement for unstressed adults is estimated to be approximately 50 ug/day; the estimated requirement for infants and children ranges from 5 to 50 ug/day.
On a more practical level, however, the Recommended Daily Allowance (RDA), the average daily level of intake sufficient to meet nutrient requirements of nearly all healthy people, is as follows:
SOURCES OF FOLATE
I have listed some of the whole foods with the high amounts of folate here, though there are many other natural food sources of folate.
Avocado: 118 ug/cup
Beetroot: 136 ug/cup
Spinach, cooked: 262 ug/cup
Asparagus: 178 ug/8 spears
Broccoli: 104 ug/cup
Soybeans: 212 ug/cup
Brussels sprouts, cooked: 156 ug/cup
Mustard greens, cooked: 104 ug/cup
Black-eyed peas, cooked: 210 ug/cup
Kidney beans, cooked: 92 ug/cup
Lettuce: 80 ug/cup
Potato, cooked, medium: 50 ug/cup
Orange, medium: 29 ug
In several countries all over the world, grains and processed foods are required to be fortified with folic acid which, as stated earlier in this article, I highly recommend avoiding. The main exception to this rule is rice. Since folic acid is water soluble it will wash off when the rice is rinsed and there for it should be safe to eat.
TESTING FOR FOLATE AND FOLIC ACID
Folate levels can be testing the blood, either measuring the amount of folate in the blood serum/plasma or the concentration of folate in the red blood cells (RBC), however instead of testing I suggest increasing your folate intake and lowering your folic acid intake because the results of this lab exam should not change this course of action.
Plasma levels tend to be a short term indicator of folate levels. RBCs tend to be a better indicator of folate levels over time, however, they can be reported as falsely low, especially in cases of pregnancy, alcoholism and vitamin B12 deficiency.
The normal range of reference of plasma folate:
Adults: 2-20 ng/mL
Children: 5-21 ng/mL
Erythrocyte (RBC) levels:
Adults: 140-628 ng/mL
Children: >160 ng/mL
Folate is absolutely vital for neural tube formation of the embryo during the first eight weeks of pregnancy, when usually the mother does not even know she is pregnant yet. It is also necessary for proper formation and growth of the placenta, as well as the baby’s heart and facial structures.
Folate deficiency is considered to be the leading cause neural tube defects such as spina bifida and anencephaly (50% of cases are due to low folate during the first trimester). Low folate consumption has also been associated with low birth weight.
I will reiterate that it is very important that women who are of child-bearing age get enough folate in their diets, especially women who are trying to conceive or are already pregnant. Malformations of the neural tube of the embryo occur during the first 8 weeks of pregnancy and will mark the health of the baby for the rest of his of her life.
Women should be getting at least 400 micrograms of folate through their diets every day and 600 mcg if they are trying to become pregnant or are already pregnant.
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