Too much dairy, carbs might harm men's sperm

October 26, 2012 by Alan Mozes, Healthday Reporter
Too much dairy, carbs might harm men's sperm
New studies also suggest women's diets could affect IVF success.

(HealthDay)—Diet can have a notable impact on reproductive health, a group of new studies suggests.

One set of findings: The more carbohydrates or diary a man eats, the poorer the quality of his sperm.

Similarly, two other studies focused on in vitro fertilization (IVF), and found that women who lowered their carb intake while upping their stood better chances of becoming pregnant.

While the studies showed an association between diet and fertility, they did not prove any cause-and-effect links.

The research was scheduled for presentation this week at the American Society for Reproductive Medicine annual meeting, in San Diego.

The pair of IVF studies was led by J. B. Russell, of the division of reproductive endocrinology and infertility at Christiana Care Health Systems in Newark, Del. The two sperm studies were led, respectively, by Dr. Jorge Chavarro, an assistant professor of nutrition and epidemiology, and research fellow Myriam Afeiche, both with the Harvard School of Public Health.

"[Recent] studies have found that there appears to be a in sperm counts throughout the world that spanned the entire 20th century, and more recent studies suggest that it may have continued into the early 21st century," Chavarro said. "While this is still highly controversial, if a downward trend in sperm counts is indeed taking place, the determinants of these decline are not clear at all."

"One of the proposed hypotheses," he said, "is that exposure to environmental factors, particularly environmental estrogens, [namely] 'female' hormones, may be the . In addition, this downward trend has also coincided with a large number of changes in the population, some of which are known to affect sperm counts, most notably obesity."

The Harvard team launched two investigations exploring the impact of nutrition on sperm quality. One focused on dairy intake and the other on carb consumption.

The carb study involved just under 200 "highly physical active" healthy men between the ages of 18 and 22, most of whom were white.

A dietary analysis revealed that carbs accounted for roughly half of all calories consumed among the participants. The team found that carb intake did not appear to have any impact on sperm mobility or shape. However, it did find that the more carbs consumed, the lower the man's overall sperm count.

On the dairy front, the Harvard group found that sperm shape was less likely to be "normal" as men's dairy intake went up. This connection was particularly strong when full-fat dairy products—such as whole milk, cheese and cream—were consumed. Neither sperm count nor sperm movement seemed to be affected by this relationship.

Chavarro said that the results of both studies held up even after accounting for a number of possibly influencing factors, such as body weight, smoking history, and alcohol and caffeine consumption habits.

Two other studies focused on women undergoing in vitro fertilization.

In the first instance, 120 women filled out a three-day dietary diary before ever having IVF. The team found that those with a high protein/low carb intake had a better chance of having their fertilized eggs survive to the so-called blastocyst stage of development and becoming pregnant.

A smaller study involved 12 women who had already tried IVF and failed to become pregnant. A similar food diary analysis was conducted before a second round of IVF. The women were counseled to up their protein intake and lower their carb consumption.

The result: Successful blastocyst formation jumped from just 19 percent on the first try at IVF to 45 percent following dietary counseling. What's more, pregnancy rates similarly shot up, from 17 percent to 83 percent.

Lona Sandon, an assistant professor of clinical nutrition at the University of Texas Southwestern Dallas, said the findings "make a lot of sense."

"First of all, you would of course expect that something produced by the body would be affected by the quality of nutrition put into it," Sandon said. "For one thing, we've known for years, from the female perspective, that the quality of nutrition that a woman takes in at the time of conception or even before conception has an influence on that child's health long-term in all sorts of ways. So, it shouldn't be surprising that nutrition would have an impact on men and the quality of their , which is basically made by protein, or on in vitro pregnancy rates."

Because the studies were presented at a medical meeting, the data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.

Explore further: A high intake of certain dietary fats associated with lower live birth rates in IVF

More information: The U.S. National Institute of Child Health and Human Development has more about infertility.

Related Stories

A high intake of certain dietary fats associated with lower live birth rates in IVF

July 3, 2012
Women with a higher intake of dietary saturated fats have fewer mature oocytes available for collection in IVF, according to results of a study from the Harvard School of Public Health funded by the US National Institutes ...

Better nutrition makes for better sperm

October 18, 2011
(Medical Xpress) -- A pair of studies presented today at the 67th Annual Meeting of the American Society for Reproductive Medicine (ASRM) show a link between dietary patterns and semen parameters in men: in short, better ...

Fatty diets may be associated with reduced semen quality

March 13, 2012
Men's diets, in particular the amount and type of different fats they eat, could be associated with their semen quality according to the results of a study published online in Europe's leading reproductive medicine journal ...

Recommended for you

Opioids and obesity, not 'despair deaths,' raising mortality rates for white Americans

July 20, 2017
Drug-related deaths among middle-aged white men increased more than 25-fold between 1980 and 2014, with the bulk of that spike occurring since the mid-1990s when addictive prescription opioids became broadly available, according ...

Aging Americans enjoy longer life, better health when avoiding three risky behaviors

July 20, 2017
We've heard it before from our doctors and other health experts: Keep your weight down, don't smoke and cut back on the alcohol if you want to live longer.

Parents have critical role in preventing teen drinking

July 20, 2017
Fewer teenagers are drinking alcohol but more needs to be done to curb the drinking habits of Australian school students, based on the findings of the latest study by Adelaide researchers.

Fresh fish oil lowers diabetes risk in rat offspring

July 19, 2017
Fresh fish oil given to overweight pregnant rats prevented their offspring from developing a major diabetes risk factor, Auckland researchers have found.

High-dose vitamin D doesn't appear to reduce the winter sniffles for children

July 18, 2017
Giving children high doses of vitamin D doesn't appear to reduce the winter sniffles, a new study has found.

Scientists develop new supplement that can repair, rejuvenate muscles in older adults

July 18, 2017
Whey protein supplements aren't just for gym buffs according to new research from McMaster university. When taken on a regular basis, a combination of these and other ingredients in a ready-to-drink formula have been found ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

hemitite
1 / 5 (1) Oct 26, 2012
So much for sympathetic magic.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.