UNTIL YOU'RE READY to have a child, you might not think much about the health of your sperm. That was true for Colton Underwood, former star of "The Bachelor." He recently opened up about his infertility and the “sperm rehab” he committed to, as he and his husband set out on the path to fatherhood.
Underwood told Men’s Health that he hoped to raise awareness about men’s struggles with sperm counts and fertility—something that affects about 15 percent of men. A 2020 study review found that sperm counts have dropped more than 50 percent globally in the past five decades.
There are ways to tell how healthy your sperm is—but looking at it isn't one of them. “A semen analysis is one of the best ways to determine if you have healthy sperm,” says reproductive endocrinologist Asima Ahmad, M.D., chief medical officer and co-founder of Carrot Fertility.
The test measures the quality and quantity of your semen and sperm to help you uncover a fertility issue. It’s the most accurate way to know where your sperm stands.
“A sperm specimen needs to be collected and looked at through a microscope to evaluate if it's healthy,” says Kaylen Silverberg, M.D., a reproductive endocrinologist at Texas Fertility Center in Austin. “That's because the factors that indicate healthy sperm can't be seen with the naked eye.”
Several factors can affect your sperm quantity and quality, including age, medications, health conditions, diet, exercise levels, and testosterone levels, explains Dr. Ahmad. Here’s what you should know about healthy sperm and some signs that yours might be doing well.
What does healthy sperm look like?
First, it’s important to know the difference between semen and sperm. Semen is the thick, white substance released when you ejaculate. Semen contains sperm, which are the cells that include genetic material needed to reproduce.
According to Dr. Silverberg, when your doctor checks the health of your sperm, they're primarily looking at three factors:
- Sperm count: The number of sperm in a volume of semen.
- Sperm motility: The percentage of sperm that are alive and swimming.
- Sperm morphology: The percentage of sperm with a healthy size and shape.
Sperm is examined under a microscope to see if they’re “using their tail to swim in a straight line,” explains Lauren Bishop, M.D., a reproductive endocrinology and fertility specialist at Columbia University. “They will also look at the head to make sure it appears oval. The tail should be long and move smoothly through the fluid.”
A normal semen analysis consists of a sperm concentration of at least 15 million sperm per millimeter of semen, motility of at least 30 percent, and at least 4 percent normally shaped sperm, according to the World Health Organization. A low sperm count or sperm that doesn’t move well could lead to infertility.
While you can’t tell by looking at your semen if it contains healthy sperm, Dr. Ahmad suggests talking to your doctor if you notice any changes, such as that semen is thicker or waterier than usual, discolored yellowish or greenish, or contains traces of blood. This might signal an infection, injury, or something else.
Signs That You Likely Have Healthy Sperm
Several habits and characteristics are associated with healthy sperm. Still, the only way to truly know how healthy yours is is to get tested. But, here are some signs your sperm may be healthy:
You hit the gym regularly.
Men who get their blood pumping with moderate to vigorous exercise have a higher sperm concentration than guys who don't work out at that intensity, research shows. Exercise may increase the expression of antioxidants throughout the body, so regular gym sessions could actually prevent free radicals from damaging sperm cells.
Regular exercise also helps you maintain a healthy weight, Dr. Ahmad says. This could lower your risk for obesity and other chronic health conditions, which have been shown to lower sperm counts.
You have a slimmer waistline.
Research shows that a larger male waist circumference has been linked to lower sperm counts. Carrying too much weight in your midsection could interfere with the release of sex hormones, as well as the production and development of sperm.
“If someone has a smaller waistline as compared to someone who may have obesity or metabolic syndrome with a larger waistline, the former may have better sperm quality, but other things need to be taken into consideration beyond that,” Dr. Ahmad explains.
You have a softer-looking face.
Having a masculine-looking mug might actually hurt you below the belt, according to a study in the Journal of Evolutionary Biology. The researchers discovered that men who had faces that were rated as manly—i.e., wider and broader—tended to have poorer semen quality than more feminine-faced guys.
One possible reason is the “trade-off hypothesis.” Simply put, men have a fixed amount of energy available to devote to reproductive resources, and that energy must be distributed to a number of different components.
“If a male consumes more resources on semen production, he may have fewer resources available for developing attractive secondary sexual traits, like facial masculinity,” says study author Jukka Kekäläinen, Ph.D.
You stay away from saunas and hot tubs.
The scrotum is a few degrees cooler than the core body temperature, which is ideal for sperm, Dr. Ahmad says. Activities like saunas, hot tubs, or hot baths could increase the temperature of the testes and potentially lower sperm count.
In a 2013 study, healthy Finnish men with normal sperm counts spent 15 minutes in a sauna a few times a week for three months and experienced lower sperm counts. The saunas lowered their scrotal temps by 5.4 degrees Fahrenheit. The decrease lasted for about three months but returned to normal after six months. The study didn’t track their fertility, however.
You take steps to protect yourself from Covid.
Research presented at the 2023 annual meeting of the European Society of Human Reproduction and Embryology found that men who had Covid had lower sperm counts for longer than three months after they recovered—and the sperm they do have are not strong swimmers.
Sperm counts can dip by as much as 20 percent. The study authors believe the findings mean Covid could be capable of doing long-term damage to the male reproductive tract, even for men who’ve had mild cases. This is most likely due to the inflammation the virus triggers.
Prevention is key. Keep track of how much Covid is circulating where you are, when new variants emerge, and when the numbers climb, mask up indoors or in crowds. Also keep up with your vaccinations.
You love to eat fish—and generally have a healthy diet.
If your favorite protein sources are bacon and sausage, your semen might be paying the price. Research has shown that men who eat the most processed meat have significantly lower counts of normal-shaped sperm compared to those who consume the lowest amounts.
Fish, on the other hand, could have a protective effect. Guys who ate the most fish—especially salmon and tuna—had a 65 percent greater sperm concentration than those who ate the least.
Credit fish’s omega-3s, since long-chain polyunsaturated fatty acids play a role in sperm production, the researchers say. So, if you’re looking to strengthen your swimmers, sub out your pepperoni pizza topping for anchovies.
An overall healthy diet full of fresh fruits and vegetables and whole grains can also positively impact your sperm. Dr. Ahmad says the Mediterranean diet is one of the best for fertility and health in general.
You skip the briefs.
A 2018 study found that men who wore boxer shorts instead of tight-fitting underwear had 25 percent higher sperm concentrations and 17 percent higher sperm counts than those who wore briefs.
Loose-fitting underwear may lower the temperature of your scrotum, where the testicles are located, and improve semen quality, the study suggests. There’s also evidence that elevated testicular temperatures may hinder sperm production, he says. So if you want to be on the safe side, let your junk breathe.
Your job is physical.
A 2023 study found that guys who do heavy lifting at work (literal heavy lifting, like moving weighty objects) had 46 percent higher sperm concentration and 44 percent higher total sperm count than men who have more sedentary jobs.
If you don’t happen to work on a construction site or pack moving vans, add weights to your workout, increasing the pounds you lift gradually to garner some of the same benefits.
Your voice isn't super deep.
Researchers found that while women rated low-pitched voices as more masculine and attractive, husky-voiced men had lower concentrations of sperm in their ejaculate, according to a study published in PLOS One.
Testosterone levels may be one possible explanation for this, according to the study. Testosterone is associated with more masculine facial features and lower voices, but too much of it might actually suppress sperm production.
You avoid smoking and drinking too much alcohol or caffeine.
Taking drugs, smoking, drinking alcohol excessively, and a hefty caffeine intake can all affect sperm negatively, Dr. Ahmad says.
Minimizing or cutting out these habits could improve sperm quality, she adds. Millions of new sperm are being produced each day, and it takes about three months for a sperm to reach full maturity.
“Therefore, if someone was a heavy smoker and had a poor semen analysis and then quit and rechecked his sperm in four months, it wouldn’t be surprising to see an improvement,” Dr. Ahmad says.
You try to avoid single-use plastics.
You’ve probably been hearing a lot about microplastics. A 2024 study published in Toxicological Sciences found significant traces of 12 kinds of microplastics in human and canine testes. Experts believe this could be connected to declining sperm counts.
Another study found that men who had the highest levels of BPA (or, bisphenol A, a chemical found in plastics) in their urine had a significantly lower percentage of motile sperm.
Scientists aren’t exactly sure what’s behind the semen squeeze, but they think BPA might affect the estrogen and androgen activity in the epididymis in the testicles. And this could hinder the normal development of sperm.
When to Get Your Sperm Checked Out
It’s always a good time to educate yourself about your fertility, Dr. Ahmad says. So, any time you’re worried about the health of your sperm, ask your doctor about getting a semen analysis.
It might also good idea to get checked if you’re dealing with a chronic medical condition, such as obesity or type 2 diabetes, and want to have children one day, she adds. These conditions can affect your sperm health.
Doctors can recommend the best course of action if an abnormality is found, such as further testing or lifestyle modifications, Dr. Ahmad says.
