Vitamin link to healthy sperm
Publication Date:20/03/2008
Doctors have found a link between the amount of a vitamin called folate in men's diets, and the health of their sperm. But the researchers say it's too early to say if eating more folate-rich foods, or taking supplements, is good for sperm.
What do we know already?
Women are advised to take supplements of folate when they are pregnant, or trying to get pregnant. That's because folate helps the unborn baby to develop normally. Taking extra folate helps prevent babies getting conditions like spina bifida in the womb.
We know less about whether a man's diet is important when he is trying to get his partner pregnant. But we know the health of a man's sperm can have an effect on whether the woman gets pregnant, and on how the baby develops.
The researchers in this new study looked at sperm with genetic faults. Like eggs from the mother, sperm contain genetic information that tells the growing baby how to develop. If the genetic information from the sperm or egg is faulty, the baby can't develop properly. The baby may be born with a condition like Down's syndrome, or the woman might have a miscarriage.
Most men have some sperm with genetic faults (usually between 1 and 4 in 100 sperm). But this varies a lot between men. This study looked at whether there was a link between how much folate men had in their diet, and how much of their sperm was faulty. They looked at both the amount of folate in the food men ate, and whether they took supplements.
Folate is found naturally in leafy green vegetables like spinach, and pulses like lentils and beans. Supplements of folate are called folic acid.
What does the new study say?
The study showed that men with high intakes of folate had less faulty sperm. Overall, men eating the most folate (over 722 micrograms a day) had 20 percent to 30 percent less faulty sperm than men eating less folate. It would be difficult to get this amount of folate from food alone. For example, spinach has about 100 micrograms of folate per serving, so you would need to eat a large amount to get to 700 micrograms. The men in the study who were getting over 722 micrograms of folate were taking supplements as well as getting folate from their diet.
Tell me more about the study's findings
The 97 men in the study were asked to fill in a questionnaire about their diet, including any food supplements they took. They also gave a sperm sample, which was checked for levels of faulty sperm. The researchers then compared the results, along with other information about the men, such as whether they smoked and how old they were.
The men in the study were healthy, didn't smoke and most of them took vitamin pills. Their ages ranged from 22 to 80.
Where does the study come from?
The study was carried out by researchers at the University of California in the United States. It was published in a medical journal called Human Reproduction, owned by Oxford University Press.
How reliable are the findings?
The study was well done, and showed there may well be a link between sperm health and folate. But the study was not designed to find out whether low folate levels actually cause faulty sperm, or whether taking folic acid could help men have healthier sperm. The researchers said they would need to do another type of study, called a randomised controlled trial, to find that out.
That's because lots of other things other than folate could have caused the differences in faulty sperm levels. For example, men who had more folate in their diet also had more vitamin C, vitamin E, beta carotene and zinc. And men who take vitamin tablets are also likely to look after their health in other ways not measured in the study.
Also, the study didn't look at whether men who ate lots of folate were more likely to have healthy children.
What does this mean for me?
The link between folate and healthy sperm sounds interesting, but it's too early to say what it means for couples trying for a baby. If other studies confirm that extra folate is important for healthy sperm, then men might be advised to take folic acid while they are trying for a baby. But we need more research before that happens.
Eating a healthy diet, including green leafy vegetables and pulses, is a good idea whether you're trying for a baby or not.
What should I do now?
There's no need to take any action as a result of this study. If you are planning a baby and want to know how best you and your partner can prepare, ask your GP for advice.
Some men might be tempted to take folic acid, to try to reduce the risk of having faulty sperm. But we don't know for sure that this is either helpful or safe. Having higher than normal levels of folic acid in your body might be harmful for some people. For women planning a pregnancy, or who are pregnant, we know that the benefits to your baby of taking folic acid outweigh any risks.
From:
Young SS, Eskenazi B, Marchetti FM, et al. The association of folate, zinc and antioxidant intake with sperm aneuploidy in healthy non-smoking men. Human Reproduction. (Published online 19 March 2008)
To find out more about fertility problems for men and women, see our information on fertility problems.
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This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
