Folic Acid Boosts Sperm
Folic acid may improve men's chances of fathering a child, The Guardian reports. Women have long been encouraged to take folic acid when trying for a baby, but a new study has found "a link between high levels of the nutrient in men's diets and the genetic quality of their sperm," the newspaper says.
The study behind the story is a small cross-sectional survey of 89 healthy, non-smoking male volunteers. It found a link between folic acid intake and the frequency of abnormalities in sperm cells. By virtue of its design, limited conclusions can be drawn from the study and the results may have arisen by chance. Randomised controlled trials are needed to explore this relationship properly.
Where did the story come from? Dr Suzanne Young and colleagues from the University of California, the Lawrence Livermore National Laboratory, and the Lawrence Berkeley National Laboratory carried out this research. The study was funded by the National Institutes of Health, the Environmental Protection Agency and the United States Department of Energy. It was published in Human Reproduction, a peer-reviewed medical journal.
What kind of scientific study was this? Healthy sperm should have one copy of each sex chromosome (X or Y). Aneuploidy means the sperm contains an abnormal number of chromosomes. About 1% to 4% of a healthy male's sperm have some type of abnormality of this kind. Why these abnormalities happen is poorly understood and the role of nutrition has not been explored.
In this small cross-sectional study, researchers contacted 97 volunteers who were healthy, non-smoking, current or retired employees of a university research laboratory. Participants were sent a questionnaire to collect information about their sociodemographic characteristics, medical and reproductive history, and lifestyle. The questionnaire also included a food frequency section that looked at the type and amount of foods eaten daily. Participants were also sent instructions for semen collection, a sterile container and a protective thermos to provide a sperm sample. To ensure completion and accuracy, participants were contacted by telephone and the food frequency question was completed within a week of providing the sperm sample.
The researchers analysed the sperm samples to determine whether they had any abnormalities. They looked for abnormalities associated with the genetic disorders Klinefelter's, triple X, XYY, Turner and Down's syndromes. Eighty-nine men were available for analysis after excluding those with low sperm counts or unusable food consumption data. The researchers used statistical methods to assess whether there was any relationship between the frequency of different types of abnormality (per 10,000 sperm) and low, moderate or high daily intake (from diet and through supplements) of different micronutrients (vitamin C, vitamin E, beta-carotene, folate and zinc). The researchers also took into account some factors that could also affect sperm health, e.g. disease history, body mass index, occupational history and use of tobacco, alcohol or caffeine, among other exposures.