Testosterone is responsible for some of the typical male characteristics and promotes muscle growth in both genders.
This hormone may assist in fat loss. Most men are full of testosterone. However, a few suffer from a deficiency, a problem that seems to predispose them to excessive fat gain.
Let’s discuss the potential role of testosterone in weight loss and obesity.
What is testosterone?
Testosterone is the most important male sex hormone. It is mainly produced by the testicles in men and ovaries in women. Hormones are messenger molecules that play a vital role in all body systems. They are released into the bloodstream, which carries them to their target cells.
When hormones come in contact with compatible cells, they bind to receptors on their surface and affect their function. Testosterone’s main role is to promote male characteristics like a deeper voice, increased muscle mass, stronger bones, and facial and body hair growth.
Adequate levels are also essential for the maturation of sperm cells and the maintenance of male fertility. Unsurprisingly, testosterone levels are much higher in men than in women. Yet the hormone plays several vital roles in women, too.
One of its most important functions in both genders is to maintain muscle mass and promote muscle growth and bone strength. Your levels decline with age, partly explaining age-related muscle and bone loss.
Not only does deficiency suppress muscle growth and maintenance, but it may also promote weight gain.
Deficiency May Lead to Weight Gain
Testosterone promotes muscle growth. At the same time, it may suppress fat gain. As a result, some testosterone-deficient men tend to gain fat more easily than their healthy peers.
Muscles burn far more calories than fat tissue. Lack of muscle thus puts people at a higher risk of eating too much and storing the excess calories as fat. In fact, some researchers believe that reduced muscle mass is the primary reason deficiency leads to weight gain in men.
Obesity itself may also suppress testosterone levels.
Obesity Is Linked With Low Levels
On average, obese men have 30% lower testosterone levels than those who are normal-weight.
More than 70% of morbidly obese men suffer from male hypogonadism, or testosterone deficiency, a disorder characterized by abnormally low levels of this hormone. Male hypogonadism may reverse with weight loss.
Scientists are not entirely sure why levels are lower in obese men, but most studies point toward the following processes.
- First, belly fat contains high levels of the enzyme aromatase, which converts testosterone into estrogen, the female sex hormone. This explains why obese men have higher estrogen levels than normal-weight men.
- Second, high aromatase and estrogen activity reduces the production of gonadotropin-releasing hormone (GRH). Lack of GRH leads to lower levels of luteinizing hormone, which in turn reduces the production of testosterone.
Put simply, excessive belly fat appears to suppress testosterone levels.
Do Supplements Cause Weight Loss?
The term “testosterone supplement” can refer to three things: illicit anabolic steroids, testosterone replacement therapy, and testosterone boosters.
Illicit Anabolic Steroids
Synthetic steroids related to testosterone are collectively known as anabolic steroids. The term may also refer to testosterone itself.
Some bodybuilders misuse anabolic steroids to increase testosterone beyond normal levels and boost muscle growth. Yet abusing anabolic steroids is illegal in many countries, including the US.
Healthy men with normal testosterone levels should not take anabolic steroids in any form, since long-term misuse can cause adverse side effects. These include sexual dysfunction, aggressive behavior, liver problems, and heart disease.
Some researchers have pointed out that not all of these side effects apply to testosterone itself but rather to its synthetic derivatives. In fact, testosterone plays a valid role in the treatment of some medical conditions.
It is legally prescribed to normalize testosterone levels in deficient men, a treatment known as testosterone replacement therapy.
While valid testosterone replacement therapy may promote weight loss in obese men, anabolic steroid misuse is not a recommended weight loss strategy.
Excessive muscle mass may be difficult to maintain in the long term and unused muscles tend to turn into fat over time.
Testosterone Replacement Therapy
This hormone is often legally prescribed to treat testosterone deficiency (hypogonadism) or other medical conditions. The treatment is known as testosterone replacement therapy and is performed under medical supervision. It can be administered as a supplement, skin patch, cream, or injection.
There is some evidence that replacement therapy can lead to weight loss in obese patients with testosterone deficiency.
One 56-week study in 100 obese men on a reduced-calorie diet found that injections improved weight loss by 6.4 pounds (2.9 kg) compared to those who didn’t receive any treatment. While both groups lost muscle mass as well as the fat mass on a low-calorie diet, testosterone caused significant muscle regaining during the weight maintenance period.
It leads to weight loss by promoting muscle growth, which in turn increases the number of calories burned.
It may also reduce fatigue, enhance motivation and promote greater physical activity. All of these factors play a major role in weight loss.
Testosterone Boosters
Also known as “natural testosterone supplements,” testosterone boosters increase the natural production of this hormone within your body. These supplements do not contain any testosterone and are usually plant-based.
Some boosters, such as ashwagandha, D-aspartic acid, and fenugreek seed extract, may raise testosterone levels and improve muscle growth in men who have low levels, although the evidence is inconsistent.
However, many of the health claims associated with boosters are not supported by science. For instance, Tribulus Terrestris, a supplement commonly sold as a booster, does not appear to raise levels.
Currently, no studies have shown significant weight loss with testosterone boosters, although some tend to reduce fat mass.
The Bottom Line
Adequate testosterone levels are a sign of good health.
Testosterone helps maintain muscle mass, increase the number of calories you burn and keep you motivated to stay physically active — all of which are associated with a lower risk of weight gain and obesity.
If you suspect you may be deficient, consult a doctor for a simple blood test.
A doctor will prescribe a testosterone replacement therapy, which is the most effective way to normalize your levels.
