Do You Know the Warning Signs of Low Testosterone?

First off, understand that low T can be complicated. The symptoms that you experience could have other causes. Few of the symptoms caused by low T are unique to this condition, the medical term for which is hypogonadism. “There’s no one very specific symptom, and that’s why it often gets missed,” says endocrinologist Luma Ghalib, M.D., of the Ohio State University Wexner Medical Center in Columbus. Often, symptoms develop slowly because testosterone levels tend to go down gradually as you age. “Most people attribute it to getting older and never pay attention,” she adds.

The big symptom: a significant drop in your libido. That means you think about and desire sex less than you used to—and possibly not at all. “People who have true hypogonadism, meaning their testosterone is below normal, have decreased sexual interest,” explains Dr. Ghalib. Unlike men with erectile dysfunction (ED), who want to have sex but can’t get or maintain an erection, men with low testosterone don’t care about sex. And because they don’t, they don’t seek help for the problem. “When their levels are really low, they don’t even complain,” says Dr. Ghalib, “so it may be their partners who complain.”

Another common symptom of low T: fatigue. Testosterone plays a part in metabolism, our body’s mechanism for converting the food we eat into energy, says Ranjith Ramasamy, M.D., a urologist with the University of Miami Health System in Florida. “When testosterone decreases, so does metabolism, and that means lower energy.” Dr. Ghalib agrees. She says that it goes beyond just feeling tired, though that definitely can be part of it. “They lose energy but also the will to do things,” she says. So if your get-up-and-go has got up and went, it might be time for a low T check.

If your testosterone levels drop significantly, it puts you at greater risk of anemia, a condition in which you lack enough healthy red blood cells to carry adequate oxygen to your body’s tissues, per the Mayo Clinic—which may explain some of your exhaustion and disinterest in doing much. “Severe hypogonadism can lead to mild anemia, and that can add to the fatigue and tiredness,” confirms Dr. Ghalib. Sometimes, this becomes particularly apparent in the evenings. “A less common symptom you might experience is the inability to stay awake after dinner,” says Dr. Ramasamy.

Weight gain, especially in your belly, also may signal low T levels. Like fatigue, this type of weight gain can be tied to a drop in metabolism, says Dr. Ramasamy, but the connection is not yet fully understood. What studies have shown is that as many as four out of five obese men may have low testosterone. To compound matters, low testosterone also makes it difficult to shrink that gut. “Obese men cannot lose weight effectively if they have low T,” says Dr. Ramasamy. So it can feel like an endless circle.

When your testosterone dips stays below normal, you eventually may notice that you don’t have the muscle strength or the muscle mass that you once did. That’s because testosterone plays a key role in muscle development and maintenance, though the relationship between muscle and testosterone is not entirely understood. This symptom of low testosterone is easy to overlook. After all, age-related loss of muscle, or sarcopenia, is a normal part of aging, and older men may shrug off this gradual decline in strength as something that’s inevitable.

You may experience mood swings, become irritable and even depressed if you have low testosterone. That’s because testosterone also affects your brain. Along with the neurotransmitters serotonin and dopamine, testosterone helps to regulate brain chemicals that determine how you feel. “That likely is the reason that it is involved in mood changes,” says Dr. Ramasamy. Low T can affect your brain in other ways, as well. You may notice that you’re less able to stay focused or remember things. According to 2020 scientific review, low testosterone may be a risk factor for cognitive decline, especially in older men.

Other symptoms can signal low T, too. You may notice that you have less body and facial hair, for example. As your testosterone drops, you will have a higher proportion of estrogen—a female sex hormone—in your body. One sign of that is enlarged or swelling breast tissue, a condition called gynecomastia. And, says Dr. Ramasamy, ED can occur, too, though it is much less common than a loss of your sex drive. Though not obvious, low testosterone can lead to weaker bones, a condition called osteoporosis, that ups your risk of fractures.

Dr. Ghalib advises men to recognize these symptoms as something worth paying attention to and discussing with their doctors, whom otherwise might not bring it up. “Physicians don’t often ask the right questions, so their patients never recognize that these symptoms indicate a serious condition,” says Dr. Ghalib. Curious if this is a discussion you should have with your doctor? She recommends taking an online screening test, such as the AMS Scale. Though not used to diagnose the condition—or determine that you don’t have low T—this brief test can help start the conversation.