Level of daily folic acid intake inversely related to breathlessness

A recent Japanese study examined the relationship of folic acid intake and degree of breathlessness and functional capacity among COPD patients and concluded that the lower a COPD patient’s daily folic acid intake, the more prevalent the symptoms of breathlessness. (Hirayama F, et al. Folate intake associated with lung function, breathlessness and the prevalence of chronic obstructive pulmonary disease. Asia Pac J Clin Nutr. 2010; 19(1):103-9)

So what is folic acid? According to the National Institutes of Health Office of Dietary Supplements folic acid (also known as folate) is defined as, “a water-solubleB vitamin that occurs naturally in food. Folic acid is the synthetic form of folate that is found in supplements and added to fortified foods…Folate helps produce and maintain new cells . This is especially important during periods of r apid cell division and growth such as infancy and pregnancy. Folate is needed to make DNA and RNA, the building blocks of cells. It also helps prevent changes to DNA that may lead to cancer. Both adults and children need folate to make normal red blood cells and prevent anemia. Folate is also essential for the metabolism of homocysteine, and helps maintain normal levels of this amino acid …Leafy green vegetables (like spinach and turnip greens), fruits (like citrus fruits and juices), and dried beans and peas are all natural sources of folate.”

On average, the Japanese COPD patients in the study consumed 231 micrograms of folic acid each day. By comparison, the National Institutes of Health recommends 400 micrograms daily for adults over the age of 19. Ironically, even the control subjects of the study (a random selection of Japanese adults without COPD) only consumed 261 mcg on average each day.

What is most interesting about the study is that even with the modest spread between the folic acid intake of the control subjects and COPD patients (30 microgram difference in daily consumption), the researchers found statistically significant variances in symptoms of breathlessness. Among COPD patients alone, the researchers found that the COPD patients with the highest levels of folic acid intake reported the least amount of breathlessness symptoms and vice versa. The researchers conclude that COPD patients would be well served by supplementing their dietary sources of folic acid.

In our opinion, current and former smokers would be well advised to also boost their folic acid intake. Depressed levels of folic acid and other key B-Vitamins in smokers have been reported in other studies. Low folic acid levels have been shown in these studies to be a causal element of developing a condition known as hyperhomocysteinaemia – a condition where the body produces too much of a chemical called homocysteine. Too much homocysteine in the blood has been linked to blot clots, heart attacks and stroke.

In the US, nearly all multivitamins contain at least 400 micrograms of folic acid given that this level has been deemed by the Institute of Medicine of the National Academy of Sciences as the recommended daily allowance (now referred to as dietary reference intake). In addition, many leafy green vegetables and even fortified cereals contain notable levels of folic acid. For more information about folic acid, its benefits, and food source content, click here to visit the National Institutes of Health’s Office of Dietary Supplements web site.