Older men who are planning to father a child in the near future would be well advised to eat a healthy diet.
A new study suggests that foods packed with certain vitamins and minerals can improve the quality of the DNA in the sperm of aging males.
Last week, widely reported research revealed that the sperm of older men contains an elevated level of random mutations. And the growing number of older fathers, with DNA-damaged sperm, may be contributing to the surging rates of autism, schizophrenia and other diseases among children and adolescents.
But the latest finding, published in the journal Fertility and Sterility, indicates there could be a relatively simple antidote to age-related sperm problems.
"It appear that consuming micronutrients such as vitamin C, E, folate and zinc helps turn back the clock for older men," said study co-author, Andy Wyrobek at the University of California Lawrence Berkeley National Laboratory in California.
The results are based on an assessment of 80 healthy male volunteers between 22 and 80 years of age.
The participants completed detailed diet and supplement questionnaires. From the data, the scientists calculated the quantity and type of nutrients the men were consuming. Each man's intake of nutrients was classified as low, moderate or high based on how he compared to the other participants in the study. The men also provided sperm samples that were analyzed for DNA damage, which could potentially lead to abnormal pregnancies, birth defects or diseases in offspring.
The analysis revealed that men older than 44 who consumed the most vitamins and micro-nutrients had 20 per cent less sperm DNA damage compared to men their own age who consumed the fewest nutrients.
This means that older men can essentially safeguard their sperm by consuming a healthy diet. In fact, the older men who consumed the most vitamins and minerals could essentially produce the same quality of sperm DNA as the younger men.
"The older guys in the highest intake [of micronutrients] group had the same level of DNA damage as the younger men," said Dr. Wyrobek.
In younger men, a higher intake of micronutrients didn't improve the quality of the DNA in their sperm. The benefit was observed solely among the older men. But, of course, they are the ones must vulnerable to sperm DNA damage – and therefore have the most to gain from an improved diet.
The researchers noted that certain vitamins act as antioxidants that neutralize free radicals, unstable oxygen molecules that could damage the DNA in sperm.
"I think this study sends a very positive message," said Dr. Wryobek. "It shows that, if you are an older man, you can reduce your sperm DNA damage down to that of a young man simply by eating a healthy diet that includes at least the recommended daily allowance for each of these micronutrients. And you don't have to overdose yourself on supplements to do it."
More research will be needed to confirm the findings. And future studies will have to determine if a higher intake of vitamins and micronutrients in older men actually improves their fertility, reduces the risks of abnormal pregnancies and results in healthier offspring.