The 5 Best Supplements and Vitamins for Men in Their 40s

Once you blow out the candles on your 40th birthday cake, there's not much (at least yet) that you need to add to your to-do list health-wise. You have a few more years until most of the additional health screenings (think: colonoscopy, prostate cancer screening) are recommended, per the U.S. National Library of Medicine.

But if you're noticing some physical changes, that's not your imagination. "As we age, the body isn't the same as it was at 20 years old. That's OK, but it's important to be cognizant of physiological changes," says Chris Mohr, PhD, RD, a Kentucky-based dietitian. If you're looking to support these physiological changes, there are some key nutrition choices you can make.

Here, we outline which vitamins and minerals (and a small handful of other nutrients, too) cisgender men need in their diets in their 40s. (More research is needed to fully understand nutritional needs of trans men and people of other genders who were assigned male at birth.)

"There aren't any studies that show an obvious positive impact of daily vitamins in a person with a balanced diet," says Starr Steinhilber, MD, MPH, internal medicine physician and associate professor of medicine at the University of Alabama School of Medicine. "However, supplements do have a role in filling nutritional gaps."

As we age, our taste buds and senses change. For some, that means less well-balanced meals, which can lead to nutritional deficiencies, Dr. Steinhilber says.

"Adding daily vitamins to your routine is generally low risk, so a multivitamin, which includes most of your important vitamins and minerals, will cover you if you happen to be nutritionally deficient and don't know it," she says.

That said, before adding any vitamins or supplements to your daily regimen, check with your doctor to make sure they won't interfere with other medications you're taking or underlying medical conditions.

How much vitamin D adults need doesn't bump up until 71 years of age, according to the Office of Dietary Supplements (ODS). That said, D is one of those vitamins most of us could stand to get more of into our diets. In fact, nearly 30 percent of American adults may be deficient in vitamin D, per an April 2018 study in the ‌British Journal of Nutrition‌.

That's not too surprising when you consider it's a vitamin only in a limited number of foods — oily fish like salmon, tuna and trout, as well as liver and egg yolks. Most of us get our vitamin D via fortified foods, such as milk, breakfast cereals, maybe orange juice.

And yes, while your skin can make vitamin D when it's exposed to the sun's UV rays, many experts agree that's not ideal because of the skin cancer risk, according to the ODS.

If you choose to supplement with vitamin D, experts recommend choosing D3 as it's believed to raise your D blood levels more effectively than D2.

"Take a 25-hydroxy vitamin D blood test after 3 months of supplementation to assess and potentially adjust your dosage," Mohr says. "Your optimal blood levels should be 50 and 80 ng/ml year-round."

Starting at the age of 31, how much magnesium a man needs each day increases ever so slightly to 420 milligrams (up from 400 milligrams), according to the ODS. Magnesium is a crucial mineral — playing a key role in protein synthesis, blood pressure and blood sugar control, bone health, sleep and even how regular your digestion is.

"Magnesium is essential for relaxing the smooth muscles within the blood vessels," Mohr says. "While this makes it important for cardiovascular health, research also supports magnesium's benefits for healthy sexual function as it relates to blood flow."

There are a wide range of foods high in magnesium (leafy greens, whole grains, nuts and seeds), yet 48 percent of Americans don't get enough, according to the ODS.

All B vitamins are what's considered "essential," meaning our bodies can't make B12 on their own, according to the National Institute on Aging.

"This vitamin is found mostly in animal products, and a well-balanced [omnivorous] diet is usually adequate for our human B12 needs," Dr. Steinhilber says. "The most notable exception is vegan diets, which typically do not contain enough B12."

Even if your B12 intake isn't low, you may still have low levels in your body — especially at 40 and beyond. B12 absorption through the GI tract and storage in cells is complex: "It involves three organs and many enzymes working together. Because this process becomes less efficient with age, even well-nourished adults may have decreasing levels over time," Dr. Steinhilber says.

"Taking a multivitamin should be enough to get adequate B12, unless blood tests suggest you are low," Mohr says. Based on this expert advice, we've rounded up the best multivitamins for men that also deliver vitamin B12.

This is another mineral we sometimes fall short on, especially as we age, according to the ODS.

Zinc is widely applauded for its immunity-supporting benefits, but it's also linked with prostate health, according to a November 2022 study in the ‌European Journal of Epidemiology‌. That's key for people with prostates who have hit or surpassed the 40-year mark.

"Omega-3s are notoriously under-consumed," Mohr says. "And while including fish in your diet is always wise, so is adding an omega-3 supplement."

Omega-3 fats support heart health, and heart disease is the leading cause of death in American adults, per the Centers for Disease Control and Prevention.

Supplements, as a category, aren't regulated by the Food and Drug Administration as rigorously as drugs are. Unfortunately, there's no guarantee that you're actually getting what's on the label.

That's why it's so important to look for products with third-party testing verification on their labels.

The ODS lists the United States Pharmacopeia (USP) and the NSF as examples of organizations offering third-party quality testing for supplements.

Their seals on supplement packaging not only verify products meet quality criteria for purity and potency, they help shoppers know what they're getting.