Vitamin B6 levels are low in the general population and in arthritis and Parkinson’s disease, according to findings from three new studies.
In the first large study of vitamin B6 in the general population, researchers measured blood plasma levels of vitamin B6 in 7,822 males and females at least one year old. Nearly 25 percent of those who did not take supplements had low levels of vitamin B6, as did 11 percent of supplement users. Four groups were more likely than most to have low vitamin B6 levels, including women of childbearing age—especially those taking or who had taken oral contraceptives—male smokers, non-Hispanic African-American men and men and women over age 65. Three in four (75 percent) of women who had taken oral contraceptives and did not take vitamin B6 supplements had very low levels (deficiency) of B6. Investigators noted that the federal government uses the same blood plasma measure to set the recommended daily allowance (RDA) for vitamin B6 and that even those who said they consumed more than the RDA had low vitamin B6 levels.
In an arthritis study of women over age 55, including 18 women with rheumatoid arthritis (RA) and 33 healthy women, researchers measured blood levels of vitamin B6, folate, fats and signs of inflammation. Participants weighed the food they ate for seven days and described their pain and ability to perform daily tasks. Compared to the healthy women, women with RA had lower levels of vitamin B6, folate and more inflammation. Because the women in both groups consumed the same amounts of nutrients, doctors theorized that those with RA do not absorb vitamin B6 as well as healthy people and may need to take supplements.
In a Parkinson’s disease (PD) study, researchers examined the diets of 5,289 healthy participants over age 55 and followed up for 10 years. Those who consumed at least 231 mcg of vitamin B6 per day were 54 percent less likely to develop PD than were those who consumed less than 185 mcg per day.