Testosterone Replacement (TRT)
Common brand names: AndroGel, Testim, Depo-Testosterone, Axiron, Testopel
Three nutrients listed against this medication. The most severe is marked critical.
At a glance
One of the three is marked well documented. The other two carry their own evidence levels.
At a glance
- Hematocrit / Iron BalanceCritical · Well documented
- ZincMild · Traditionally cited, limited evidence
- Vitamin D3Mild · Traditionally cited, limited evidence
Color shows how serious each listed effect is. The label beside it shows how strong the evidence is. The cards below explain each one and show its evidence.
Nutrients it can lower
Mechanism, Proposed link, not measured: testosterone therapy suppresses the body's own testosterone production, and zinc is a cofactor in testosterone synthesis. The cited trial ran the other way: restricting dietary zinc lowered testosterone in healthy adults. Testosterone therapy has not been shown to deplete zinc.
Common signs, Reduced fertility, impaired sperm production, immune suppression
Prasad et al. (Nutrition, 1996; PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 8875519): dietary zinc restriction lowered serum testosterone in healthy adults. That is the reverse direction; testosterone therapy is not shown to deplete zinc.
Zinc 25–45 mg daily is a range in common use, not from a trial cited on this row. Prasad restricted dietary zinc in healthy adults and measured testosterone, which is the reverse direction; neither testosterone therapy nor HCG was studied.
Mechanism, Testosterone stimulates erythropoiesis, raising hematocrit. Elevated hematocrit increases clot and stroke risk. Iron stores can be depleted if erythropoiesis outpaces intake.
Common signs, Polycythemia (elevated clot risk, stroke risk if hematocrit >54%)
Calof et al. (J Gerontol, 2005; PMID 16339333): TRT increases polycythemia risk 5.7x. Endocrine Society Guidelines mandate hematocrit monitoring.
Hematocrit is monitored every 3–6 months, with therapeutic phlebotomy if above 54%. Iron is not supplemented without confirmed deficiency on TRT.
Mechanism, Proposed link, not measured: low vitamin D is associated with low testosterone, and vitamin D supplementation modestly raised testosterone in one trial, which is the reverse direction. Testosterone therapy has not been shown to deplete vitamin D.
Common signs, Suboptimal TRT response, immune insufficiency, bone loss risk
Vitamin D supplementation modestly raised testosterone (Pilz, 2011, the reverse direction); testosterone therapy is not shown to deplete vitamin D.
25(OH)D is commonly tested alongside TRT. No concentration target is established, and testosterone therapy is not shown to deplete vitamin D: the cited evidence runs in the other direction.
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It prints or saves as a single page. Whether to add a supplement for a nutrient this medication may lower is a decision for your prescriber.
Disclosure
These statements have not been evaluated by the Food and Drug Administration. Any grade on this page describes the strength of published human trial evidence in the populations studied. It is not a recommendation for any individual and is not medical advice. Starting, stopping or changing any supplement or medication is a decision for your physician.
Grades move when new trials publish. A free monthly email lists every grade EBL moved, with the reason and the trial behind it: the sign-up is on the Evidence Log →