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Hormones affect many important functions in the body, from sex drive and fertility to metabolism, sleep and energy. Here we go over eight important hormones, how they work and what changing hormone levels can mean for men's health. We also explain when it may be relevant to examine your hormone levels with a blood test.
Are you feeling more tired than usual? Maybe you've found it harder to build muscle or noticed that your sex drive has changed? There may be several explanations, but sometimes the body's hormones play a role. The hormones in our body affect everything from metabolism and sleep to fertility and muscle building.
Which hormones affect men's health?
Hormones are chemical messengers that help the body's various organs to work together. Below we list eight hormones, in no particular order, and describe their different functions.
1. Testosterone - sex drive, muscles and energy
Testosterone contributes to sex drive, sperm production, muscle mass, bone health and the formation of red blood cells - in men, the hormone is mainly produced in the testicles. With a testosterone deficiency, men can experience, among other things, reduced sex drive, fewer morning erections and reduced physical stamina. Fatigue and depression can also occur, but are nonspecific symptoms with many possible causes.
The diagnosis of testosterone deficiency is not made based on a single testosterone test or symptoms alone. When investigating, the doctor usually works to review both symptoms and repeated low testosterone values in correctly taken morning samples. The doctor also needs to assess why the levels are low.
Testosterone treatment is not a general treatment for fatigue or normal aging and can inhibit sperm production in men who want to have children.
2. LH – controls testosterone production
LH, luteinizing hormone, is formed in the pituitary gland and signals the testicles to produce testosterone. In the case of a low testosterone level, LH can help distinguish between impaired testicular function and a disorder in the regulation from the pituitary gland or hypothalamus. An elevated LH together with low testosterone can indicate a cause in the testicles, while a low or inappropriately normal LH can indicate a central cause.
3. FSH – important for sperm production
FSH, follicle-stimulating hormone, is also produced in the pituitary gland and in men it supports sperm formation in the testicles. FSH can therefore be a relevant test when investigating impaired fertility, often together with other hormones and semen analysis. However, a normal FSH level does not rule out fertility problems.
4. Thyroid hormones – affect metabolism
The thyroid gland produces the hormones T4 and T3, which affect the body's metabolism. In hypothyroidism, that is, underactive thyroid, you may feel tired, cold or depressed and gain weight. In the opposite condition, hyperthyroidism, you instead have an overactive thyroid, which can cause symptoms such as palpitations, sweating, anxiety and weight loss.
Because these symptoms can be similar to other conditions, thyroid function is often assessed with TSH and, if necessary, free T4. TSH is a control hormone from the pituitary gland, not a thyroid hormone, but is an important test for assessing thyroid function. T4, T3 and TSH are included in the thyroid test for assessing thyroid function.
5. Insulin – regulates blood sugar
Insulin is a hormone produced in the pancreas that helps the body's cells absorb and use glucose. In insulin resistance, the cells respond less well to insulin signals. The condition can occur together with abdominal obesity, high blood pressure and disturbed blood lipids and increases the risk of type 2 diabetes.
Insulin resistance often does not cause any clear symptoms. Sweet cravings, fatigue after meals or difficulty losing weight are not enough to determine whether you have insulin resistance. HbA1c and glucose tests can be used to detect impaired blood sugar regulation, but they do not in themselves determine the degree of insulin resistance.
6. Cortisol – the body's stress hormone
Cortisol, also known as our "stress hormone", is produced in the adrenal glands. It helps the body regulate, among other things, blood pressure, metabolism and reactions to stress. Cortisol levels vary naturally during the day and are usually highest in the morning. When taking a sample, the time needs to be adjusted according to what you want to examine. Cortisol is therefore a necessary hormone, not something that is harmful in itself.
Long-term stress can affect sleep and well-being, but does not automatically mean that cortisol levels are chronically elevated. Pathologically elevated cortisol production, as in Cushing's syndrome, is uncommon and can cause muscle weakness, central weight gain and skin changes, among other things.
7. Melatonin - regulates circadian rhythms
Melatonin is formed primarily during the dark part of the day and is there to help the body signal when it is night. Exposure to light in the evening, shift work and travel across time zones can affect circadian rhythms. However, sleep problems can have many other causes, such as stress, sleep apnea or irregular sleep habits.
Sleep deprivation can also affect appetite and food choices. The hormones leptin and ghrelin are involved in hunger and satiety regulation, but the results of studies on exactly how levels change with sleep deprivation vary. Melatonin is not normally included in a standard blood test for sleep problems.
8. Prolactin – can affect sex drive and fertility
Prolactin is also produced in the pituitary gland. Elevated prolactin levels can inhibit the body's regulation of sex hormones and in men contribute to lower or low testosterone, reduced sex drive, erectile dysfunction or fertility problems. Certain medications, hypothyroidism and other conditions can cause elevated values.
In some cases, elevated prolactin is due to a prolactinoma, a usually benign hormone-producing tumor in the pituitary gland. An abnormal test needs to be assessed in its context and sometimes rechecked before further investigation would be appropriate.
Does low sex drive or fatigue mean that hormones are out of balance?
It can mean that, but it is not always the case. Reduced sex drive, erection problems, fatigue and weight changes can, in addition to hormonal influences, be due to, for example, stress, lack of sleep, depression, medication, alcohol, obesity or other diseases. Erection problems can also be related to blood vessels and cardiovascular health. If the problems are recurrent or affect everyday life, it is important to seek help to get a medical assessment that can help determine which causes need to be investigated.
Which hormones can men check with a blood test?
Several of the body's hormones can be measured through blood tests. Which tests are relevant depends on what you want to examine, since different hormones provide information about different functions in the body.
At the Test Clinic you can examine several hormone values through blood tests and have your results assessed by a doctor. You can find our available hormone tests directly in the article or among our blood tests and health checks for men. If you are unsure, you are welcome to call us
