Dr. Jörg Sandmann in an expert interview: How does testosterone level develop in middle-aged men?

Testosterone hormone levels change throughout life, but can decline even in younger men and lead to symptoms such as poor performance, erectile dysfunction, and depression. If possible symptoms occur, a medical diagnosis is essential to rule out a possible testosterone deficiency.

serotalin®: Dr. Sandmann, in your clinical opinion, what are the typical signs of declining testosterone levels in men over 30?

Dr. Sandmann: The 30-year-old patient is not the typical patient with testosterone deficiency. We first need to examine the extent and when certain symptoms occur. Many people believe that sexual disinterest and erectile dysfunction are typical signs of testosterone deficiency. This is not true, as these symptoms only appear very late.

Initially, nonspecific symptoms similar to a thyroid disorder appear—for example, reduced performance, fatigue, increased fat tissue, or depression. However, patients often don't notice these initial signs and often associate them with work-related stress or other challenging situations. This is why testosterone deficiency is so often not recognized as the cause.

serotalin®: Can you briefly explain the general influence of testosterone on men's health?

Dr. Sandmann: Testosterone is incredibly powerful. It's a male sex hormone, produced in the liver from cholesterol and transformed into the actual "success hormone" in the testes. Testosterone is what makes us male. This results in the typically dark voice and other masculine characteristics. Testosterone is responsible for many metabolic processes.

It promotes muscle building and blood formation, which is why the hormone is used in doping. Typical examples are where muscle mass is desired or where oxygen is abundant, such as in cycling. Testosterone supports the formation of red blood cells and reduces the size of fat cells.

Testosterone also has a positive effect on diabetes mellitus and changes in lipid levels. There are also patients who develop depression due to their testosterone deficiency, but antidepressants are ineffective. Compensating for the testosterone deficiency, however, leads to patients feeling more productive, agile, and better. This suggests that testosterone is also needed in the brain.

serotalin®: Can you confirm that declining testosterone levels have an impact on the reproductive organs? In this context, what is the relationship between testosterone levels, fertility, and spermatogenesis?

Dr. Sandmann: Of course, testosterone affects a man's sexual function. Those with too little or no testosterone develop a decreased sexual desire and erectile dysfunction. In addition to the lack of desire, there is also mechanical inability.

Since testosterone is also involved in sperm production, this becomes particularly difficult for patients who wish to have children: Testosterone replacement therapy leads to a reduction in sperm production because we interfere with the hormonal regulatory system. The problem is therefore more significant here. Accordingly, a patient who wishes to have children must be treated differently than a patient who, for example, is 55 years old and no longer wishes to have children.

serotalin®: What options are available to men for treating low testosterone levels, and what can they do to counteract declining testosterone levels?

Dr. Sandmann: It starts with diet or with supplements like zinc , since this trace element contributes to maintaining normal testosterone levels in the blood. However, if you're talking about a significant testosterone deficiency, then zinc-containing foods won't be enough.

If you have a testosterone deficiency, then you have to compensate for the missing hormone. Just like you do with the thyroid. By supplementing the thyroid hormone, we then have to supplement the missing testosterone. Nowadays, there are two approaches in the medical field. A gel is quick to apply – it absorbs quickly and has a good effect. The second option is the injection of a testosterone depot preparation. These injections are usually given every three months because the substance is released so slowly. In the past, these preparations were effective for a much shorter period of time, so the usual duration was four weeks, but there were also many patients who needed an injection every two weeks.

The major disadvantage of this intramuscular injection therapy is that it creates a kind of wave-like effect of too much and too little testosterone. If the patient receives too little testosterone, they become weak, unable to perform, and possibly depressed. And if they have too much, they appear hyped up and may even be aggressive, which is also noticed by those around them. Therefore, long-term preparations are more effective. The major advantage of the gel is that you can optimally dose and adjust it every day.

We advise against buying products sold online, as you don't know whether they're safe or what kind of oil is used as a carrier. It's important to be aware of the risks.

serotalin®: Can you please explain how successful testosterone replacement therapies are?

Dr. Sandmann: Yes, testosterone replacement therapy is successful. Patients have shown this, too. If you imagine you're supposed to "smear" testosterone on your shoulder every day, you'll only get a prescription every three months if you benefit from it. That means if you feel better, if you exercise, and also notice that you're building muscle more easily. Additionally, fat is burned more effectively, you're somehow better able to control your diabetes, you're in a better mood, and you're more productive. You don't get a prescription every three months just so the doctor can get rid of it.

It's often more difficult to truly measure success. Successful substitution therapy through blood count replenishment is one thing, but we treat different patients and not laboratory results. The older the patients, the more diseases affect their health. One-third of diabetics have a testosterone deficiency. Patients taking opioid painkillers also frequently have a testosterone deficiency.

The same applies to patients with severe kidney dysfunction, who experience further difficulties as a result – for example, reduced blood cell count. Testosterone turns many gears, and testosterone replacement therapy can be seen to improve patients in various ways. In cases of kidney failure or diabetes mellitus, testosterone is a small but important cog in the success of treatment.

In cases of kidney failure, expensive medications are used to produce red blood cells, but testosterone is not always measured or supplemented, although testosterone replacement would be useful.

serotalin®: Are there certain foods or supplements that can help maintain testosterone levels?

Dr. Sandmann: Yes, zinc-containing supplements and meat that men who exercise enjoy eating anyway, such as red, expensive, or high-quality organic meat. In the case of a true deficiency—for example, due to childhood trauma with loss of testicular function or other reasons—this cannot be supplemented. It's a matter of individual preference.

The problem is that we have medications that reduce testosterone, and older patients with coronary heart disease, diabetes, or vascular constriction are usually given statins to lower cholesterol. The limits for bad LDL cholesterol are becoming increasingly strict. However, it must be considered that testosterone is formed from cholesterol, so cholesterol-lowering drugs can have a significant negative impact on testosterone synthesis.

Some patients don't have such low testosterone levels, but still suffer enormously. In others, treatment is necessary due to a significant deficiency, which doesn't always benefit the patient. These individual situations make treatment difficult.

serotalin®: What are your most important tips for men over 30 to optimize testosterone levels and overall health?

Dr. Sandmann: In general, men in their 30s live differently than they did in the past. My grandfather, for example, was a train driver, and other hard-working miners were also members of the workforce. Today, pizza is delivered, almost everyone has a car, and overall, little exercise is required. Everyone has become incredibly immobile. In the past, you didn't need a pedometer; you could cycle 20 kilometers, and you could eat more accordingly.

This still works today: People who do a lot of endurance and strength training and eat a high-protein diet are less likely to become overweight and diabetic than those who consume harmful substances on a daily basis. And if the liver primarily has to process large amounts of sugar and fat, testosterone levels may fall behind.

Back then, men were often already ill by the age of 60 after a physically demanding job; they would just sit by the window with their COPD (chronic lung disease) until they were "out of the window." Today, the probability of a man reaching 60 or 80 is high compared to the past. But if you don't take care of your health after the age of 30, it's like not taking care of your car but wanting to register it as a classic car later. It's important to start sport, strength training and endurance training early enough, because otherwise it won't be as effective. Anyone who is already overweight at 30 will have even more health problems at 60, as their metabolism continues to slow down. For a long time, we underestimated the value of strength training and only relied on endurance training, which was wrong.

My personal conclusion: Testosterone is an important hormone that has a bad reputation because it's used as a doping agent to enhance performance. However, this also shows that it's an extremely important and powerful hormone. If you're feeling underperforming and depressed, you should take care of it and see a doctor for a professional evaluation. There are clear standards and plenty of experienced doctors. Testosterone deficiency is easily treatable. I wish there was more focus on testosterone when typical symptoms occur in younger patients.

The other thing, since you asked about testosterone deficiency in younger patients, my conclusion would be that 30-year-olds should take better care of themselves – the way they would treat a car they want to drive as a classic car later on. The problem is, however, that men often take much better care of their cars than their health, are more likely to buy expensive oil than high-quality food, and don't train their bodies sufficiently and prepare them for old age. And I believe we can, we must, rethink this; it's very important, because we want to grow old healthily and be able to enjoy our time.

About the author:

General practitioner, author, and urologist Dr. Jörg Sandmann specializes in the field of the sex hormone testosterone. He advises his patients on the available treatment options for testosterone deficiency—including a healthy, active lifestyle.