Folic acid reduces the risk of stroke

Surprisingly many people suffer from hypertension without knowing it. That is a concealed threat, as elevated blood pressure is a common cause of stroke and premature death. However, people with hypertension who take folic acid along with their blood pressure-lowering medicine have a substantially lower risk of stroke.

Supplements of folic acid are generally recommended in connection with anemia and especially pregnancy, as it reduces the risk of neural tube defects (NTD) and heart defects in newborn babies. Folic acid supplements also play an important role for the cardiovascular system, the heart, and the brain. It is a good idea to get as much of the nutrient as possible from the diet, as many people are much better able to utilize the vitamin in its natural form (this will be addressed later on in the article).

What causes stroke?

In the United States, stroke (apoplexy) is the fifth leading cause of death and is a result of a blood clot in the brain or cerebral hemorrhage. Blood clots in the brain are mainly caused by atherosclerosis and circulating clots that wedge themselves into narrow blood vessel passages. Cerebral hemorrhage is primarily caused by poorly managed hypertension, blood-thinning medicine, and serious conditions such as cancer. Atherosclerosis and hypertension is a very unfortunate cocktail that increases the risk of stroke additionally.

Folic acid could save millions of lives globally

Because folic acid is one of the leading causes of stroke, Dr. Yong Huo and his team of researchers from Beijing University Hospital set out to investigate the effect of folic acid supplements on 20,000 adult patients who took the anti-hypertensive drug Vasotec and who had not suffered a stroke. During the study period, half of the participants took folic acid together with their blood pressure-lowering medicine, while the other half took their medicine only. Four and half years later, the researchers detected a 21 per cent lower stroke rate among those who had taken medicine and folic acid, compared with those who had only taken their medicine. The study is published in the Journal of the American Medical Association.
Because 800,000 Americans die of stroke every year, the study results suggest that supplementing with folic acid may in theory save around 200,000 American lives a year. Similar results have been seen in other studies.

Folic acid regulates homocysteine, a harmful compound that causes blood clots

According to Yong Huo's study, the two groups differed in terms of stroke caused by blood clots.
It is useful to know in this connection that elevated levels of a potentially harmful compound called homocysteine may contribute to the formation of blood clots. It is also a known fact that homocysteine interacts with folic acid, vitamin B12, and vitamin B6, and that levels of homocysteine may become too high if there is a deficiency of one or several of the mentioned vitamins. Slow metabolism, renal disease, psoriasis, and the use of various types of medicine (including birth control pills) may also cause homocysteine levels to increase.

How different forms of folic acid are absorbed and utilized

The most common term for the vitamin is folic acid (vitamin B9 is hardly ever used). Folic acid is the synthetic form that is found in vitamin pills, while folate is the natural form that you get from food. Normally, folic acid is very stable. In the body it gets converted into folate and the biologically active form, chemically known as L-5-MTHF. This is the form of the nutrient that is able to cross the blood-brain-barrier and make itself useful in the brain. It appears, however, that nearly 50% of older people have difficulty with converting folic acid to its biologically active form because their enzyme activity is reduced. It is therefore an advantage for these individuals to make sure to consume several good folate sources from the diet at the same time as taking supplements of folic acid.

Good folate sources:

Liver, legumes, cabbage, asparagus, other green vegetables, sprouts, nuts, eggs, and fruit.

Blood samples and diagnosis

Folate deficiencies are detectable through blood samples. Elevated levels of homocysteine also help to identify a deficiency.
Lack of folate is often seen in conjunction with low vitamin B12 levels.

What causes a folate deficiency?

Primary causes of deficiencies are poor diets, pregnancy, ageing processes, alcohol abuse, narcotic drugs and other stimulants, prolonged use of birth control pills and medical drugs like methotrexate (against rheumatism and cancer), where folic acid supplements are normally advised to avoid serious deficiency diseases.

References:

http://jama.jamanetwork.com/article.aspx?articleid=2205876

http://www.medicinenet.com/script/main/art.asp?articlekey=187452

http://www.healio.com/cardiology/stroke/news/online/%7Beb28b746-2cf7-4ac6-b598-21e7d9938e7b%7D/folic-acid-supplementation-reduces-stroke-risk

https://www.sundhed.dk/borger/sygdomme-a-aa/hjerte-og-blodkar/sygdomme/diverse/homocystein/