The importance of nutrition is so broad and universal when it comes to the human body that its relevance in the roles of every biological system are undeniable. Diet is directly linked to the quality of male sperm.
A recent study published in Biology of Reproduction investigated whether increasing polyunsaturated fatty acids (PUFAs), that are critical for sperm maturation and membrane function, would increase sperm quality in men consuming a Western-style diet. The research noted that that consumption of walnuts can positively affect sperm quality.
But there are also nutrients which have the opposite effect on sperm.
More than one serving of full-fat milk per day could have a negative impact on sperm quality, Harvard researchers have claimed.
The United States is the world's largest producer of pasteurized cow milk and the dairy industry dips their paws into every facet of society including education, athletics and all institutions in general. Their interest is to increase per capita consumption of pasteurized milk which is lagging behind most of the world. It seems their efforts will only make American men more sterile than they already are.
A team of scientists at the Harvard School of Public Health in Boston, Massachusetts conducted a study involving nearly 200 young men, which examined the association between dairy intake and semen quality.
They discovered that men who eat even three portions of cheese a day had poorer quality sperm than those with a lower daily intake of full-fat dairy products.
Harvard researcher Myriam Afeiche, who led the study, told DairyReporter.com that the sperm produced by men that consumed between 1.3 and 7.5 servings of dairy per day was of less quality than those with a lower dietary intake of dairy products.
The study defined a serving of full-fat dairy as ounce of cheese, a teaspoon of cream, a scoop of ice cream or a glass of full-fat milk.
"We examined whether dairy food intake was associated with semen quality," said Afeiche.
Afeiche and her team examined the association between dairy intake and semen quality by comparing the diets of 189 young men from the Rochester Young Men's Study.
"Men aged 18-22 were recruited for the Rochester Young Men's Study in 2009-2010. The relationship between dairy intake and semen quality parameters was evaluated using linear regression models."
The Harvard School of Public Health team found that the percentage of men with morphologically normal sperm decreased as the daily intake of full-fat dairy products such as milk, cheese and cream increased.
"We found that men with the highest intakes of full-fat dairy (1.3 to 7.5 servings per day) had 2.7% lower morphologically normal sperm compared to men with the lowest intakes (0 to 1.2 servings per day)," Afeiche said.
The team's findings were presented at the American Society for Reproductive Medicine's (ASRM) annual conference in California earlier this month.
Afeiche added, however, that further research would be vital before any health recommendations could be made.
"While we know that some semen quality parameters relate to the probability of conception, we did not directly assess whether the observed differences in semen quality had any influence in fertility. It is important that further studies address this question," she said.
Mae Chan holds degrees in both physiology and nutritional sciences. She is also blogger and and technology enthusiast with a passion for disseminating information about health.