Deteriorating diets may be the reason behind declining sperm count in men, a study suggests.
American researchers discovered that young men who ate a diet full of junk food had considerably fewer swimmers than those who ate healthy.
The team analyzed the sperm quality of nearly 3,000 Danish men, who also reported their typical eating habits.
Pizza, fries and sweet dessert lovers had a 25 percent lower sperm count than those who ate a lot of fruits, vegetables, and fish.
Their sperm count – a measure of fertility – was 122 million on average compared to 167 million of those who ate a healthy diet.
The findings, published in the journal JAMA Network Open, fuel the fear that modern lifestyles lead to ‘spermageddon’.
The quality of sperm has slowly declined in Western countries in recent decades. At the same time, we have become fatter and less active.
American researchers have found that young men who eat a diet full of junk food have a considerably lower sperm count (122 million) than those who eat healthy (167 million). Those who ate primarily vegetarian had a sperm count of 151 million per ml
The researchers at Harvard T. Han Chan School of Public Health, Boston, wanted to delve deeper into the theory that bad diets are behind men’s sperm.
In Denmark, men have to undergo a physical examination at the age of 18 to determine their suitability for the army. This means that a sperm sample is provided.
Researcher Feiby Nassan and colleagues analyzed samples from 2290 men, with an average age of 19, from 2017 to 2019.
Questionnaires collected information about the diet of the participants. Men reported how often they consumed food from a list of 136 items in the last three months.
Four food groups were drawn; the western pattern, the cautious pattern that was the healthiest, the open sandwich pattern, typical of a Danish person, and a vegetarian pattern with little meat.
Overall, the median total sperm count was 140 million sperm cells per ml, well within the normal range of 40 million to 300 million established by the World Health Organization.
HOW TO COMPARE ANY DIET?
The western pattern: number of sperm cells of 122 million
Foods mainly: pizza, French fries, processed meat, snacks, sauces based on dairy products, potatoes, sugary drinks, sweets and desserts, refined grains, organ meat, energy drinks, fruit juices, beer and breakfast cereals.
The cautious pattern: sperm count of 167 million
Foods mainly included: vegetables, fish, poultry, fruit, nuts, eggs, grains and water.
Men ate less added sugars.
The open sandwich pattern: sperm count of 146 million
Foods mainly included: Danish bread, cold cuts, mayonnaise, fish, herbs, low-fat and low-fat dairy products, snacks, bread-based sauces, eggs and wine.
The vegetarian pattern: number of sperm cells of 151 million
Foods mainly included: sugary drinks, refined grains, energy drinks, vegetables, fish, fruit, nuts, herbs, tea, soy milk, eggs, tomatoes, coffee
The healthiest eaters had an average sperm count of 167 million, followed by those who ate predominantly vegetarian, with 151 million.
Men who filled foods with more calories, sugar and salt, such as pizza, fries and soft drinks, had an average sperm count of 122 million.
Their sperm still counts within ‘fertile’ limits, because less than 20 million is considered low.
One in six men (16 percent) in the entire cohort had a low sperm count.
Men who took recreational drugs, smoked, had a high BMI, or used muscle-enhancing supplements were excluded from the study.
The men had also taken blood samples, from which the scientists measured levels of hormones related to fertility.
Men who ate a western diet rigidly had higher testosterone levels. However, the ratio of their sperm-producing hormones was out of balance.
The researchers speculated that a western diet leads to a certain degree of reduced activity in the hypothalamus – a region in the brain that plays a crucial role in the release of hormones – which influences sperm production.
Joint senior authors Drs Jorge Chavarro and Neil Jørgensen wrote: “Our results are consistent with our hypothesis that adherence to healthy dietary patterns is associated with better testicular health.”
Allan Pacey, professor of andrology at the University of Sheffield, commented on the findings at MailOnline: ‘The results of the research fit in with the general picture that has emerged in recent years.
For men who ate a rigid ‘Western food’ diet, including pizza, fries, processed meat and sugary drinks, their sperm count was 122 million – 25 percent lower than healthy eaters
“It is generally the case that men who eat more meat and processed food have poorer sperm quality than men who eat a lot of fruit and vegetables.”
The number of sperm is one of the many parameters of a man’s fertility, in addition to sperm motility and sperm quality.
A low number of sperm cells means that fewer sperm cells are ejaculated in the seed than normal. The medical name is oligospermia.
It can influence the chances of a man becoming a father, because the chance that a sperm fertilizes an egg, resulting in pregnancy, is reduced.
A low sperm count or poor sperm quality is, according to the NHS, either the cause or a contributing factor for infertility in 45 percent of couples trying to have a baby in the UK.
Nevertheless, many men with a low sperm count can still have children.
The researchers from the latest study said that dietary changes are a possible approach to improving reproductive results in men.
Professor Pacey said that men should commit to a healthier life to reap the benefits.
“Men must be aware that it takes three months to produce sperm. If a man changes his diet on Friday, it doesn’t improve his sperm by Monday, “he said.
Adam Watkins, a professor of reproductive biology, University of Nottingham, said that diet is only one variable that affects sperm.
‘Of course, diet and a healthy lifestyle (not smoking, drinking within the recommended amounts of alcohol and not using recreational drugs) often go hand in hand.
“Ultimately, a poor diet – and this can be either too little or too much of certain food groups or nutrients – is probably a factor that underlies the worldwide decline in sperm quality.
“The impact of this decline on male fertility, however, still needs to be clarified.”
The term “spermageddon” is confused after studies suggest that the existence of humanity is threatened by declining sperm.
Scientists have feared that people with extinction could be threatened if the number of sperm cells continued to fall as rapidly as in the last four decades in Western countries.
A study by Israeli researchers in 2017 found that the number of sperm cells has almost halved since the 1970s in men from the US, Europe and Australia.
They noted that there was no “leveling,” which would suggest a continuing trend to reduce sperm count in the future.
Dr. Hagai Levine said: “I think the data serves as a wake-up call because I am personally concerned about that [human extinction] if we do not tackle current environmental problems. “
WHY DOES MEN’S SPERM QUALITY HAVE EVERY YEAR?
Sperm quality has dropped significantly in recent decades, by 1.8 percent a year, according to researchers at Sidney Kimmel Medical College in Philadelphia in 2018.
Although there is a debate going on about the underlying causes of these declines, these factors play a central role in scientific research:
Diets and obesity
The quality of the diet has changed dramatically in Western countries in the last 50 years. People tend to eat more calories, meat, dairy, fat, sugars, and refined, processed foods.
The NHS says: “Eating a healthy, balanced diet and maintaining a healthy weight is essential to keep your sperm in good condition.”
Studies suggest that adherence to generally healthy foods, full of fruits and vegetables, can improve various sperm parameters.
A 2017 study in the Netherlands found that men who are healthy had a higher sperm concentration, total sperm count and sperm mobility.
The Mediterranean diet, rich in healthy fats and low in sugar and red meat, has shown that it improves sperm quality in studies in Germany and Spain.
And diets focused on seafood, poultry, whole grains, legumes, fruits and vegetables have shown that they increase sperm quality in studies in North America, Europe, the Middle East and Asia.
Pollution and chemicals
There is growing concern and there are indications that environmental exposure explains the decline in sperm quality.
A study at the University of Sao Paulo, Brazil, showed that mice exposed to toxic air had a lower number and had poor quality sperm compared to those who had inhaled clean air since birth. The study looked at fine dust (PM), small particles that penetrate deep into the lungs and penetrate the blood stream. PM is mainly released by car fumes.
According to the World Health Organization, endocrine disrupting chemicals (EDCs) are likely to be one of the main causes of male infertility.
These chemicals can disrupt normal endocrine function by disrupting the synthesis, secretion, transport, action, or elimination of natural hormones.
EDCs are mostly man-made, found in a variety of materials and products, ranging from pesticides, food and makeup. They are swallowed or may sink into the skin.