Low testosterone, commonly shortened to “low T,” is a medical condition that can have some undesired effects on the body. Testosterone levels are not always clear without tests, but there are some symptoms that could point to a deficiency in this important hormone being the cause. Here are seven signs to look for.

1. You Are Experiencing A Decreased Sex Drive

Low testosterone levels frequently result in a lower sex drive. This can be difficult to objectively measure because every person’s libido is different, meaning it is important to look for changes in you personally. You may find yourself not wanting to have sex as often as before. Although this can be because of relationship issues or stress, low T might also be the cause. Men with low testosterone levels commonly have issues getting and maintaining erections as well. This includes spontaneous erections and erections that occur during sleep.

2. Increase In Body Fat

An increase in body fat, particularly an odd shift in fat distribution and with no other apparent cause, might be a symptom of low testosterone. This can be especially noticeable on the chest, where men with low testosterone sometimes experience growth of the breast tissue. This is commonly believed to be a result of the balance between testosterone and estrogen in men being thrown off.

3. You’ve Suddenly Started Losing Hair

Testosterone levels normally decrease as a man ages, which can contribute to hair loss. This normally might not be enough of a reason on its own to receive treatment for low testosterone, but significant unexplained hair loss can be a reason to talk to your doctor. Hair loss can occur all over your body in addition to on your head. Testosterone treatment may or may not restore lost hair, but it can stop any additional loss.

4. You’ve Started Having Mood Swings

Low testosterone can result in mood disorders such as depression and mood swings. Men with low testosterone might become irritated easily and the mood changes can be drastic and severe. If you or others around you have begun to notice strange mood swings you can’t explain, it’s worth talking to your doctor about a possible testosterone deficiency.

5. Your Muscle Or Bone Mass Is Decreasing

A loss in muscle or bone mass is another possible symptom. This can lead to conditions such as osteoporosis and a greater likelihood of injury. Fortunately, there are treatments available if decreasing muscle or bone mass is caused by low testosterone. Note that this symptom can be caused by other conditions so it is important to rule out other causes as well.

6. You Are Fatigued Or Have Problems Concentrating

Testosterone helps maintain good cognitive function and energy levels. If low T is present, men may begin experiencing problems concentrating or experience abnormal levels of fatigue. This can be especially noticeable at work if you are no longer putting in good performance. You may also notice that you can no longer exercise as much as before. Alternatively, men with low testosterone might experience insomnia or sleep disturbances. They are also more likely to develop sleep apnea, a disorder where breathing starts and stops during sleep. It can be potentially dangerous and should be addressed.

7. You Are Having Trouble Fathering A Child

Testosterone is produced in the testicles and is critical in the formation of healthy sperm. If levels are low, a man’s sperm count also tends to go down, which can make fathering a child difficult or even impossible. If a couple is struggling to conceive, they should see their healthcare provider to try and find out what the cause might be. This includes checking the man’s testosterone levels to determine if that is the cause of the infertility.

If you are experiencing any of these symptoms you should bring them up to your doctor. Your doctor can then investigate to determine if the source of the problem is low T. If your levels are low and you are experiencing problematic symptoms, you will likely be put on a treatment plan.