The relationship between testosterone replacement therapy, Vitamin D, and Zinc
Hormone replacement therapies have become very popular among men in recent years. New methods and new studies support these processes.
During the last few years, testosterone replacement therapies have emerged as ways to enhance the effects of testosterone replacement therapies. Among them are physical exercise, good nutrition, weight control, and vitamin D consumption, either through food, sun, or supplements.
What is testosterone?
It is the dominant male sex hormone which belongs to the androgen group. 90 to 95% of testosterone is produced in the testes, specifically in the Leydig cells, through “steroidogenesis” (manufacture of steroid hormones), a process regulated by the brain and the pituitary gland through LH (luteinizing hormone).
What is its function?
Testosterone is the most important male hormone. During puberty, it handles the growth of body hair, muscle development, and deepening of the voice, among other characteristics. In adult men, it intervenes in sexual desire, maintains muscle mass, acts in the distribution of body fat, and helps produce sperm. Women also have testosterone in their bodies, but much lower amounts.
Testosterone in men is also responsible for bone density and white blood cell production, influencing mood, sleep, and cognitive functions. In addition, it promotes protein synthesis and is related to insulin sensitivity, glucose, and lipid metabolism.
What happens when it decreases?
From 35 to 55 years of age, testosterone levels can decrease naturally, affecting men physically, psychologically, and emotionally. Low testosterone levels influence sexual desire, mood, sleep, and muscle and fat changes.
Also, certain conditions, medications, or injuries can lead to low testosterone levels. When these levels decrease too much, then specific symptoms appear, among them:
- Decreased or lack of sexual desire.
- Erectile dysfunction.
- Low sperm count.
- Insomnia or having a restful sleep.
- Decreased muscle strength.
- Decreased muscle size.
- Loss of bone mass.
- Increase in body fat.
- Depression and emotional lability.
- Lack of concentration.
Hormone replacement therapy
When the symptoms become more pronounced and affect the different spheres of a man’s life to a greater extent, hormone replacement therapy is considered.
Before hormone replacement therapy is shown, laboratory blood tests are performed to verify that the levels are below average. The doctor will also perform a complete physical evaluation and look for probable causes.
Hormone replacement therapy helps control the symptoms of testosterone deficiency. The drug used is a synthetic form of testosterone, and the treatment is called “testosterone replacement therapy or TRT.”
There are several ways of administering TRT. They have developed different methods of administration, each with its pros and cons that can be tailored to the needs of each patient, including:
- Intramuscular injections.
- Subcutaneous injections.
- Transdermal gel.
- Nasal gel.
- Transdermal patches.
- Oral testosterone.
- Buccal testosterone.
- Testosterone pellets.
Role of vitamin D on testosterone
Vitamin D is involved in many physiological processes in the human body. It is one of the oldest biologically active compounds in the body. Its receptors are present in various tissues, organs, and systems, such as
- Skeletal muscles.
- The thyroid gland.
- The cardiovascular system.
- The immune system.
- The reproductive system.
Its primary function, or the best known, is the absorption and maintenance of calcium levels in the bones. However, that is not the only association with calcium.
Serum calcium is essential for male reproductive function, especially for spermatogenesis, sperm motility, and acrosome reaction. Therefore, since vitamin D primarily regulates calcium metabolism, vitamin D could influence the synthesis of male sex hormones.
Vitamin D and zinc, magnesium, and B vitamins are necessary to form testosterone. In addition, it regulates testosterone levels by inhibiting aromatase (an enzyme that starts the conversion of testosterone into estrogen and, therefore, can reduce its ranks).
Several recent studies have suggested that vitamin D is essential in producing sex steroids. This suggestion was made based on evidence of the expression of vitamin D receptors (VDR) and vitamin D metabolizing enzymes, which are in Leydig cells, Sertoli cells, germ cells, and spermatozoa.
Thus, testosterone production by Leydig cells is under the tight control of LH, which induces steroidogenesis by increasing cyclic AMP production and intracellular concentration of calcium in Leydig cells, where vitamin D could exert an influence by modulating this LH response.
So, vitamin D has become one of the most critical and well-known vitamins in the world, but, despite its importance, almost half the population of the USA is vitamin D deficient, and an even higher percentage has levels below those desired. Likewise, in Spain, between 40 and 97% of people suffer from this deficiency, with the incidence increasing with age.
Role of Zinc on testosterone
As mentioned above, zinc also plays a key role. Zinc prevents the excessive function in the body of an enzyme called aromatase, which converts testosterone into estrogen.
This is based on the following assumption: “an excess of estrogen, produced by the abnormal activity of the aromatase enzyme, leads to the suppression of testosterone production through the inhibition of luteinizing hormone released by the pituitary gland”.
Therefore, maintaining zinc levels in the range may help keep testosterone levels in men, naturally and with replacement therapies.
Several investigations have shown that vitamin D functions as a natural testosterone stimulant.
The authors hypothesize that serum vitamin D levels may directly affect gonadal functioning, with biological plausibility derived from the presence of the vitamin D receptor (VDR) in the testes, hypothalamus, and pituitary gland.
Many studies support this theory:
1. A 12-month study found that supplementation with about 3000 IU of vitamin D3 per day increased testosterone levels by about 25%.
2. Another study of 2,299 men in 2017 concluded that vitamin D regulates male androgen metabolism. Showing that:
- Those with a higher amount of vitamin D generated a higher testosterone level in the blood.
- It simultaneously increased the quality and mobility of spermatozoa.
3. According to an observational study in Korea blood levels of vitamin D and testosterone were analyzed in 652 men over forty. Concluding that:
- Participants with vitamin D deficiency were 2.65 times more likely to have testosterone deficiency than those with normal levels.
4. Likewise, an article published by the Medical University of Graz in the journal Hormone and Metabolic Research shows the relationship between testosterone levels in men and vitamin D levels. They gave participants a dose of 3,000 IU of vitamin D or a placebo for one year. After that time, the vitamin D value in the group taking the vitamin doubled, and the testosterone level also increased.
5. Finally, another study on vitamin D and testosterone levels in men aged 65 to 89 years showed that the higher and healthier the vitamin D level, the higher and healthier the testosterone levels of the test subjects.
Is it recommended to take vitamin D with testosterone replacement therapy?
According to the evidence, the answer is yes. In fact, including vitamin D enhances the effect and increases testosterone levels.
There are two natural sources of vitamin D: the first is from the sun, and the second is from food. Some foods rich in vitamin D are:
- Fatty fish, such as trout, salmon, tuna, and mackerel.
- Fish liver oils.
- The liver of cattle.
- Egg yolk.
- Cheese also contains small amounts of vitamin D.
- Mushrooms provide some vitamin D.
- Fortified foods such as some animal and vegetable kinds of milk.
The third source of vitamin D is artificial, from multivitamin supplements or vitamin D-only supplements widely used today for different purposes.
In testosterone replacement therapy, they show these supplements immediately. But it is always essential to perform laboratory tests that reflect the actual levels.
The standard therapy is usually positioned between 2000 to 3000 IU of vitamin D per day; however, each physician will establish the amount and time for each patient.
Currently, the Spanish Society of Endocrinology and Nutrition (SEEN) recommends maintaining serum concentrations of 25OHD between 30 and 50 ng/ml (75-125 nmol/l) to achieve the health benefits of vitamin D.
We cannot forget that zinc is essential to cover many areas necessary for the proper functioning of our body, including the reproductive system, specifically related to testosterone levels. That is why sufficient consuming doses of zinc will be of great help for hormone replacement therapy.
Many foods contain this mineral, but the ones that stand out the most are:
- Oysters are the best source of zinc.
- Red meats.
- Seafood such as crab and lobster.
- Fortified breakfast cereals and whole grain cereals.
- Dairy products.
Also, as with vitamin D, multivitamin supplements are stated in these cases. These can come alone or combined with calcium and magnesium. This amount is 15 mg/day for adult males, always under medical supervision.
Consult with your doctor about the possibility of supplementing your replacement therapy with vitamins and minerals to boost and maintain better testosterone levels. And don’t forget that a healthy diet can provide the requirement that you need. Click for more information about our testosterone replacement therapy program.