XY Files Blog

Medically reviewed articles on testosterone, hormones, fitness, and longevity, so you can make informed decisions about your health.

Does nicotine increase testosterone or quietly wreck it?

Veedma's editorial team: Evidence-based men's health

Nov 20, 2025 · 10 min read

In observational studies, male cigarette smokers average about 15% higher total testosterone and 13% higher free testosterone than non-smokers, likely because nicotine alters liver hormone metabolism and slows testosterone breakdown. That “smoker’s paradox” can still coincide with erectile dysfunction and infertility as smoking damages blood vessels and testosterone-producing Leydig cells, so higher lab numbers don’t ...

Can Vitamin D impact testosterone?

Veedma's editorial team: Evidence-based men's health

Oct 28, 2025 · 15 min read

Vitamin D can modestly raise testosterone in men who are truly vitamin D deficient (25-hydroxyvitamin D below 20 ng/mL), likely because the testes contain vitamin D receptors and activation enzymes that may influence Leydig cell testosterone production. Here is how to tell when correcting vitamin D is a meaningful lever. It also explains when low ...

L carnitine benefits for men: What it can and cannot do for fat loss, workouts, and testosterone signaling

Veedma's editorial team: Evidence-based men's health

Oct 25, 2025 · 16 min read

L-carnitine can modestly improve endurance style training output and may support sperm motility in selected men, but it is not a guaranteed fat loss or testosterone shortcut. This evidence-based guide breaks down which l carnitine benefits are real, what dose and timeline matter, and how to use it like a structured experiment instead of a ...

Sauna health benefits for men: A safe routine for heart health and recovery

Veedma's editorial team: Evidence-based men's health

Oct 21, 2025 · 15 min read

Regular sauna use is associated with meaningful sauna health benefits in men, especially for cardiovascular health and blood pressure, when sessions are frequent enough to raise core temperature and are done safely.[2] The upside is real, but the best data are mostly observational, so the win comes from a repeatable routine, not extreme heat or ...

Testosterone Сypionate: Relief you can feel, but what about fertility?

Veedma's editorial team: Evidence-based men's health

Oct 17, 2025 · 14 min read

Testosterone cypionate can relieve true hypogonadism (diagnosed in men with persistent symptoms plus biochemical evidence on repeated morning testing, using decision thresholds of total testosterone below 350 ng/dL and Free Testosterone below 100 pg/mL in the proper clinical context), but it commonly suppresses LH and FSH and can sharply reduce or shut down sperm production. ...

How testosterone replacement therapy injections can boost your mood

Veedma's editorial team: Evidence-based men's health

Aug 08, 2025 · 13 min read

In men with persistent symptoms of hypogonadism and repeatedly low biochemical values by Veedma’s thresholds (typically total testosterone below 350 ng/dL and/or free testosterone below 100 pg/mL on repeat morning testing), testosterone injections that restore levels to the mid normal range can modestly improve mood and vitality by increasing androgen signaling in brain reward and ...

Veedma recovery plan for muscle gain in men: How to protect testosterone and sleep hormones

Veedma's editorial team: Evidence-based men's health

Aug 06, 2025 · 14 min read

A hormone-focused recovery plan can improve muscle gain in men by supporting healthy testosterone rhythms and deep sleep growth hormone pulses while reducing chronically elevated cortisol that slows repair. If your lifts have stalled, the highest value move is often not a new program, it is better recovery habits you can track like training. “Most ...

Maximize workout results with hormone-friendly training techniques

Veedma's editorial team: Evidence-based men's health

Aug 06, 2025 · 14 min read

You can improve strength and body composition by keeping resistance sessions focused and intense, centered on compound lifts at about 70, 85% of your 1-rep max with moderate volume and adequate rest, while prioritizing protein and sleep to support recovery and prevent chronically elevated cortisol. Here’s how to structure training and recovery so mechanical tension, ...