MEN who eat too much meat increase the risk of becoming infertile, according to a study.
Experts warned those planning to have a baby should ensure they eat limited amounts of chicken, beef and lamb.
The study, conducted at the University of Worcester, found that a high-protein diet lowered men’s testosterone levels by 37 percent.
For the average man, this would lead to medically low testosterone levels (hypogonadism), the experts said.
Lead researcher Joe Whittaker, a nutritionist, told The Sun: “Low testosterone levels cause low sperm count, which is the main factor in male fertility.
“In our study, high-protein diets caused low testosterone levels, so it’s very likely they also caused low sperm count, which would reduce male fertility.”
Low testosterone levels are also linked to chronic diseases such as heart disease, diabetes and Alzheimer’s.
The paper, published in the journal Nutrition and Health, described the effects as “protein poisoning,” where the breakdown of protein into ammonia becomes toxic.
It suggested that the body may be too busy trying to fix protein intoxication that it suppresses the production of testosterone.
Mr Whittaker said: “It would take one to two weeks to see the first signs of protein intoxication such as nausea, diarrhea and low testosterone levels (including associated symptoms such as low sex drive).”
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How much meat is “too much”?
For the study, Mr. Whittaker and colleagues compiled the results of 27 studies involving 309 men.
It found that high-protein diets, which tended to be low-carb trade-offs, consistently affected testosterone and elevated cortisol.
A high-protein diet was one in which 35 percent of calories came from proteins such as meat, fish, eggs, dairy, beans and legumes.
For a man eating 2,500 calories a day, that would mean he’s consuming about 865 calories of protein.
For example, this equates to three eggs for breakfast (240 calories), one chicken breast for lunch (212 calories) and 250g ground beef for dinner (420 calories).
Mr Whittaker estimated that around one per cent of men consume that much protein – and said it would be “primarily men trying to build muscle and those who depend on lots of protein shakes”.
“Bodybuilders and weightlifters (even the amateurs in regular gyms) are notoriously devoted to dieting and can achieve it [35 per cent] sometimes,” he said.
“Anecdotally, I’ve heard numerous men complain of mild symptoms of protein intoxication like abdominal pain and diarrhea when trying to bulk up.
“Anything over 35 percent protein for more than two weeks is dangerous territory.
“It might be safe for some people, but it’s not well studied and what little research there is on it strongly suggests it will cause harm.”
Mr Whittaker recommended staying under a 30 percent protein limit, or 15 to 25 percent if he’s planning to start a family.
He added: “Reduce alcohol consumption, quit smoking, exercise regularly, lose weight when necessary, and eat a diet rich in whole, unprocessed, nutritious foods such as meat, fish, eggs, fruits, vegetables, nuts and legumes.
“Avoid processed and/or sugary foods like the plague.”
Eating protein is vital and has a number of benefits, including muscle repair and a longer-lasting feeling of satiety.
This is why it is so favored by both the bodybuilding community and those trying to lose weight.
Many celebrities such as Kim Kardashian, LeBron James and Meagan Fox have promoted them.
And they’re the foundation of Atkins and the more modern keto diet.
The British Nutrition Foundation says it recommends protein amounts per day based on how much we need per kilogram (kg) of our body weight.
“For adults, that’s 0.75 g per kg of body weight. Current recommendations are 56 g/day for men and 45 g/day for women (based on a body weight of 75 kg for men and 60 kg for women).
“In the UK, on average men eat around 85g and women around 67g of protein per day.
“So, on average, we eat more than we need to. It’s likely that most of us are getting enough protein.”
The take away is moderation is key.
https://www.the-sun.com/health/4916675/eating-too-much-meat-raises-risk-male-infertility/ Study claims that eating too much meat increases the risk of men becoming infertile