Men’s Health · Research Review · 2026

What Nicotine Is Actually Doing to Your Testosterone, Mental Health, and Sexual Function

The biohacker community says nicotine boosts testosterone. The research says something more complicated — and a lot more damaging.

Respiro · April 2026 · 6 min read

There is a version of nicotine that circulates in biohacker circles. It sharpens focus, boosts dopamine, elevates testosterone, and — in the right dose — makes you more productive, more driven, more alpha. The Zyn under the lip is not an addiction. It is a stack.

The research tells a different story. Not a simple one — the relationship between nicotine and male hormones is genuinely complicated. But when you look at the full picture, across testosterone, mental health, and sexual function, the picture is not flattering for nicotine.

The testosterone myth

Some studies do show higher total testosterone in smokers. This is the fact that circulates online, and it is technically true. A large 2024 study published in Scientific Reports examined data from nearly 8,000 adult males and found that up to a certain threshold, higher cotinine levels (the marker of nicotine exposure) were associated with higher total testosterone.

But here is what that finding does not tell you. Total testosterone is not the same as bioavailable testosterone. What matters for libido, muscle growth, energy, and sexual function is the testosterone your body can actually use — free testosterone, unbound to proteins.

The myth
"Nicotine raises testosterone. I have the studies."
Nicotine appears to raise total testosterone in some studies. But it also raises sex hormone-binding globulin (SHBG) — the protein that binds to testosterone and renders it inactive. Higher total T with higher SHBG means less usable testosterone, not more. The number goes up. The benefit does not.

The relationship is dose-dependent and nonlinear. The 2024 Scientific Reports study found that at lower exposure levels, cotinine was associated with slightly higher testosterone — but past a certain threshold, the association reversed. Heavy, chronic use is where the damage accumulates. Nicotine also damages Leydig cells — the testicular cells responsible for producing testosterone. Animal studies show consistent dose-dependent decreases in testosterone production with long-term exposure. Whatever short-term signal exists, the long-term trajectory points down.

What it does to your mental health

Nicotine feels like it reduces anxiety. This is the experience of every person who has ever lit a cigarette or reached for a pouch in a stressful moment. It is also almost entirely an illusion.

What nicotine actually does is create the anxiety it temporarily relieves. Regular nicotine use establishes a baseline state of mild withdrawal that the next dose resolves. The relief feels like relaxation. It is actually just the absence of withdrawal. A non-user in the same stressful situation does not feel that spike of anxiety in the first place.

“Long-term nicotine users are not calmer than non-users at baseline. They are only calmer than themselves in withdrawal — which is a state non-users never enter.”

The EAGLES trial — the largest study ever conducted on smoking cessation and mental health — found that quitting nicotine, including with varenicline, was associated with improved mental health outcomes even in patients with pre-existing psychiatric conditions. The anxiety you think nicotine is managing is largely nicotine-induced.

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The erectile function problem

This is the clearest and most under-discussed consequence of chronic nicotine use. Erections are a vascular event. They require blood flow to the corpus cavernosum — the spongy tissue in the penis. Nicotine is a potent vasoconstrictor. It narrows blood vessels throughout the body, including the ones that matter here.

ED
Risk significantly elevated in chronic nicotine users across multiple published studies
NO
Nitric oxide production impaired by nicotine — critical for blood vessel dilation
Weeks
How quickly erectile function begins improving after quitting nicotine

Beyond vasoconstriction, nicotine impairs nitric oxide synthesis. Nitric oxide is the signaling molecule that triggers smooth muscle relaxation in penile tissue — the biological mechanism of an erection. Research suggests that depleting nitric oxide makes erections harder to achieve and maintain. This applies to cigarettes, vaping, and pouches — the delivery method changes, the vasoconstriction does not.

A 2022 study published in the American Journal of Preventive Medicine found that e-cigarette users had significantly higher rates of erectile dysfunction than non-users after controlling for other variables. The association between nicotine use and ED is consistent across multiple study designs, though researchers note that isolating nicotine as the sole cause in human studies is methodologically difficult. The signal is real. The exact magnitude varies.

What quitting actually does

The good news is that most of these effects are substantially reversible. Within weeks of quitting nicotine, blood vessel function begins recovering. Nitric oxide production normalizes. The anxiety baseline drops. Testosterone production, freed from the suppression of chronic nicotine exposure, can recover over months.

The brain that felt calm only with nicotine rediscovers what actual baseline calm feels like. Most people who successfully quit report better sleep, reduced baseline anxiety, improved mood, and — frequently — improved sexual function within the first 1-3 months.

The receptor-level intervention that makes quitting most achievable is varenicline — the same medication that works for cigarettes works for vaping and pouches. It binds to nicotine receptors, quiets the withdrawal, and blocks the reward if you slip. The 12-week quit rate in clinical trials is approximately 44% — more than triple cold turkey.

Your body is ready to recover.

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This article is for informational purposes only and does not constitute medical advice. The research cited reflects published clinical and scientific literature. Individual results vary. Consult a healthcare provider before starting any medication or cessation program.