Is turning 40 really a big deal for men’s health?

Many men feel that 40 is a watershed moment when everything starts falling apart. Is it all in their minds? Experts help separate fact from myth.

Last updated: Jan 19th, 2024
Man’s 40th Birthday

Some birthdays mean more than others. They’re milestones, turning points that we see coming from a distance and either celebrate or dread (or a little bit of both). If you’ve got 40 fast approaching, you may be wondering just how much of the weight we attach to turning 40 is justified — especially from a medical perspective.

Are there significant changes you’ll notice when you wake up that morning? Or will it be a day like any other? And if changes are coming along with middle age, what are they, and when will they arrive?

We wanted to get to the bottom of these questions to demystify some of the common ideas about getting older that we attach to certain ages. So we reached out to a handful of experts to learn what physiological and psychological changes a man turning 40 can expect in the near future.

Thankfully, it’s not all bad news, but there are some critical things to consider if you want to make your 40s as healthy and productive as the years that preceded them.

Your 40s are when old habits start to catch up with you

We got our first question out of the way quickly, and it turns out you likely aren’t going to wake up on your 40th birthday and feel any different than you felt the day before. “It’s not like there’s a switch that’s flipped as soon as you turn 40, in terms of your physical health,” says Cory Rice, DO, an internal medical physician and medical director for Biote.

Throughout the years to come, however, Dr. Rice notes that your 40s are when the effects of bad habits from your 20s and 30s might set in. For example, Dr. Rice says that many men experience weight gain in their 40s — weight they find tougher to lose than in their 20s or 30s. And if it’s easier to gain and tougher to lose, eating the way you did when you were younger might be dangerous.

Even men who have been slim their whole lives are prone to weight gain in their 40s if they have an unhealthy lifestyle. In one study of 549 men aged 42 to 64, men who were thin in early adulthood gained more visceral fat (fat found deep in the abdominal cavities) than men who had a higher body mass index in early adulthood.

Dr. Rice says that the lesson here is to use your 40s and the years immediately preceding them to put some healthier habits in place, like

  • Eating nutrient-rich foods
  • Minimizing alcohol use
  • Exercising regularly
  • Getting adequate sleep
  • Finding healthy ways to deal with stress

All these habits can lower your risk of cardiovascular disease, which is the number one cause of death in the United States.

You can also use your 40th as an opportunity to get a sense of where your overall health stands, for which Dr. Rice recommends doing a comprehensive metabolic lab panel. This test is a simple blood test that can be done by your healthcare provider and will indicate how fast (or slow) your metabolism is, what shape your kidneys and liver are in, and what your blood sugar levels are. Dr. Rice says that it can also be helpful to get a lipid panel to screen for your risk of cardiovascular disease. This test measures the cholesterol and triglycerides in your blood, unhealthy levels of which lead to cardiovascular problems down the line.

Sexual health is ever-evolving — and not always for the better

For many men, a sense of masculine identity is inextricably tied to their virility. That might make the 40s a tough decade, as changes in sexual health are common, and they often include decreases in libido and fertility and increased incidence of erectile problems.

Omer Raheem, MD, a board-certified urologist specializing in men’s sexual health and the chief medical officer at Zuri Fertility, says, “Reduced libido, or a decrease in sexual desire or drive, can affect about 5-10 percent of men and tends to become more common with age.” Dr. Raheem explains that low libido and ED can be related to various factors, including physical health, stress and psychological factors, and low testosterone levels.

With so many potential underlying causes, you should speak to a doctor and try to get to the root of the problem, but if physiological changes or a new medication are to blame, you have multiple options. If it’s related to low testosterone levels, then testosterone replacement therapy can be an option. “For psychological causes, mental health therapy can help address the issue. In some cases, medications like PDE-5 inhibitors, such as Viagra or Cialis, can be used to manage low libido if it's medication-related,” he says, which he adds also can help with ED.

What if you’re functioning just fine, but you want to start a family? Having kids after 40 is becoming a lot more common for men, and while men’s fertility in middle age isn’t talked about as much as women’s, both Dr. Raheem and Dr. Rice say that as men get older, their fertility can be affected. “Age can lead to changes in sperm quality and DNA integrity, which may increase the risk of unsuccessful pregnancies or miscarriages,” Dr. Raheem says. Studies show that sperm quality starts to decrease at 39, so men in their 40s who want to have kids might want to get a semen evaluation to assess their fertility and sperm quality.

With all these possible tests and problems cropping up, it’s nice to know there’s one test men can typically forego in their 40s: prostate screening. Most men can wait until 50 for this; prostate cancer is most commonly diagnosed between ages 65 and 74. There is one major caveat to this, though: If prostate cancer runs in your family or you have certain genetic conditions (like the BRCA1 or BRCA2 gene) that puts you more at risk, Dr. Raheem says to get screened in your early 40s. He adds that Black men are also at increased risk for prostate cancer and should be screened in their early 40s.

A change in mindset

While there won’t be any meaningful physical differences between a 39-year-old you and 40-year-old you, there is one thing that might shift in a way you could feel as early as that first morning of your 40s. Your mindset could change significantly. After all, the male life expectancy in the US is just under 80. What might it mean to you to have more days behind you than ahead?

Psychotherapist Avigail Lev, PsyD, says her male clients often start thinking differently around this time. “How a man identifies himself may change,” she says. Some men in their 20s and 30s may have defined themselves by bachelorhood or career pursuits. But by their 40s, men with families can start to look inward, prioritizing their clan over themselves.

For some men, it’s also a time that can lead to feelings of restlessness. “There can be this question of ‘what’s next?’” She says that overcoming this restlessness can require coming up with new goals or shifting focus to another area of life to be more important, such as caring for one’s family or mentoring others.

“Forty marks the beginning of the life stage of psychodevelopment called generativity versus stagnation, as defined by psychoanalyst Erik Erikson,” Dr. Lev says. In this stage, she says a person’s focus shifts from self-centered goals to one’s legacy and what they might leave behind that will outlast them.

What you’ll leave behind when you’re gone might be a little too far off to consider, though, even at 40. What you need to ask yourself is what you want your 40s to look like. If you’ve got some time before 40 hits, maybe you could commit to getting in the best shape of your life or learning a new language and treating yourself to a vacation where you can try it out. Set yourself an ambitious goal to help combat feelings of restlessness and try to find new, tasty foods that also happen to be good for you (they’re out there!). Forty doesn’t have to be the end of anything, but it can be the beginning of something excellent.



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