How to Lower Cortisol and Increase Testosterone Naturally

Cortisol and testosterone are regulated by two interconnected hormonal systems, and when one is chronically elevated, the other tends to suffer. The good news is that several lifestyle changes can push both hormones in the direction you want simultaneously, because the same behaviors that calm your stress response also support healthy testosterone production. The less-good news is that some of the most popular advice online oversimplifies the science or overstates the size of the effects. What follows is a practical breakdown of what actually moves the needle, grounded in what the research shows.

Why These Two Hormones Are Linked

Your brain runs two parallel hormonal command chains. One controls your stress response and ends with cortisol being released from your adrenal glands. The other controls reproduction and ends with testosterone being produced in the testes (or ovaries, in smaller amounts). These two systems are not independent. Research has long established that manipulating one system affects the other, making it difficult to change cortisol without also influencing testosterone, and vice versa.¹ One proposed mechanism is that cortisol directly interferes with testosterone production in the Leydig cells of the testes by inhibiting the enzymes responsible for converting precursor molecules into testosterone.²

This cross-talk means that strategies aimed at lowering cortisol can sometimes raise testosterone as a secondary effect, and vice versa. But it also means you should be skeptical of any single trick that claims to dramatically shift both hormones at once. The relationship is real, but the magnitude of change from any one intervention tends to be modest unless your starting point involves a genuine problem like chronic sleep deprivation, severe caloric restriction, or untreated anxiety.

Sleep Matters More Than You Think, but Differently Than You Expect

Sleep is probably the single most underrated factor. Both hormones follow daily rhythms tied to your sleep-wake cycle. Cortisol peaks shortly after waking, with the strongest surge occurring in the early morning hours around 3:40 to 3:45 a.m. in a typical sleeper, and drops to its lowest levels in the evening.³ Testosterone follows a similar daily rhythm, peaking in the morning and declining through the day, and this rhythm tracks your actual sleep pattern rather than the clock on the wall. Studies of night-shift police officers found that testosterone’s daily rhythm completely followed the sleep-wake cycle regardless of how many consecutive night shifts the men worked.⁴

When you consistently cut your sleep short, cortisol levels in the late afternoon and evening rise, even though your overall 24-hour cortisol may not change dramatically.⁵ That elevated evening cortisol is the problem. Healthy cortisol should be low in the evening to prepare your body for sleep. When it stays high, you get a vicious cycle: elevated cortisol disrupts sleep quality, and poor sleep further elevates evening cortisol. Studies in both men and women have confirmed that restricted sleep raises afternoon and evening cortisol while flattening the normal daily decline.⁶⁷

The testosterone side of the sleep story is more nuanced than social media suggests. A systematic review and meta-analysis found that short-term partial sleep deprivation, the kind most people experience during a busy week, did not significantly reduce testosterone levels. Only total sleep deprivation, staying awake all night, produced a clear drop.⁸ A controlled study that restricted young men to roughly four hours of sleep for four to five nights similarly found no statistically significant change in testosterone compared to adequate sleep.⁹ This does not mean sleep doesn’t matter for testosterone, but it does suggest that a few bad nights won’t crater your levels the way some content creators claim. Chronic, severe sleep loss over weeks or months is a different story, and fixing genuinely poor sleep remains one of the highest-return investments you can make for hormonal health overall.

Exercise and the Acute Hormone Spike

Resistance training reliably produces an acute spike in testosterone during and immediately after a session. Hypertrophic-style lifting with relatively short rest periods appears especially effective at triggering this response. One study found that total-body hypertrophic protocols with 60- or 90-second rest intervals produced significant increases in total testosterone measured immediately after training and at 15 and 30 minutes post-exercise, without a corresponding significant rise in cortisol.¹⁰ High-power resistance exercise, think explosive movements with moderate loads, also produced a large testosterone response in trained men, again without significantly elevating cortisol.¹¹

There is a catch, though. The way you organize your workout can influence whether cortisol rises alongside testosterone. Research on high-intensity interval resistance training found that certain workout organizations, particularly randomized exercise ordering, triggered the highest spikes in both cortisol and testosterone, and these hormonal effects lingered into the following morning.¹² The practical lesson here is that training hard enough to raise testosterone will sometimes raise cortisol too, and that is fine acutely. The acute cortisol rise from exercise is not the same as chronic stress-driven cortisol. Problems emerge only when training volume or intensity outstrips your recovery capacity over weeks, a state sometimes tracked by the testosterone-to-cortisol ratio, which has been studied as a marker for overtraining syndrome and peak athletic performance.¹³

What You Eat and How Much

Diet influences both hormones, and the two biggest dietary levers are total calorie intake and the ratio of carbohydrates to protein.

Severe calorie restriction reliably lowers testosterone. A study of men practicing long-term caloric restriction found that it reduced both total and free testosterone compared to men eating at maintenance, and this effect was independent of how lean the men were.¹⁴ One of the proposed mechanisms is that prolonged energy deficit ramps up cortisol production, which then suppresses testosterone synthesis.² If you’re dieting aggressively for fat loss, this creates a temporary hormonal trade-off you should be aware of. Moderate deficits with adequate protein are less likely to cause meaningful testosterone drops than crash diets.

The carbohydrate-to-protein ratio matters in a way that surprises many people. In a controlled study where men ate either a high-carbohydrate or high-protein diet for ten days, the high-carb diet consistently produced higher testosterone and lower cortisol compared to the high-protein diet.¹⁵ This does not mean you should avoid protein, but it does suggest that very-low-carb diets may work against your hormonal goals. Research on athletes undergoing intense training found that a low-carbohydrate diet caused the free testosterone-to-cortisol ratio to drop by about 43%, while a moderate-to-high carbohydrate diet kept it stable.¹⁶ If you train hard and eat very few carbs, the combined stress may push cortisol up and testosterone down more than either factor would alone.

Vitamin D is often promoted as a testosterone booster. The evidence is mixed. A Mendelian randomization analysis suggested a possible causal link between higher vitamin D levels and modestly higher total testosterone. But multiple supplementation trials where participants took high-dose vitamin D weekly for eight to twelve weeks found no significant differences in testosterone levels compared to placebo.¹⁷ Correcting a genuine deficiency is worth doing for many reasons, but expecting a meaningful testosterone bump from supplementing when you’re already in a healthy range is not well supported.

Stress Management Techniques

Mindfulness-based practices like meditation and mindfulness-based stress reduction (MBSR) have been studied specifically for their effects on cortisol. A meta-analysis of controlled trials found that mindfulness interventions produced a moderate reduction in cortisol levels.¹⁸ An eight-week MBSR course for beginners lowered morning cortisol while also improving sleep quality.¹⁹ That sleep improvement is a bonus, since as we saw earlier, better sleep helps keep evening cortisol in check.

A particularly interesting study looked at whether brief mindfulness training could shift both hormones simultaneously in response to acute stress. After just seven sessions, young men who practiced integrative body-mind training showed higher testosterone and lower cortisol after a stress test compared to a relaxation-only group.²⁰ The researchers attributed this to the two hormonal systems being co-regulated, so a technique that calms one axis can release the other from suppression. You do not need to become a dedicated meditator. Even consistent practice of breathing exercises, progressive relaxation, or similar techniques can modestly lower cortisol over time.

Supplements That Have Some Evidence

The supplement market for testosterone and cortisol is enormous, and most products have little to no rigorous evidence behind them. Three supplements stand out as having at least some research support, though none should be considered dramatic game-changers.

Ashwagandha (Withania somnifera) has the strongest body of evidence for affecting both hormones. A recent meta-analysis pooling 23 randomized controlled trials with over 1,700 participants found that ashwagandha supplementation significantly reduced cortisol and increased testosterone in men by an average of roughly 57 ng/dL, though it did not raise testosterone in women.²¹ An individual trial reported a 23% reduction in cortisol and about an 11% increase in testosterone in the ashwagandha group over eight weeks, while the placebo group showed no change.²² These effects are most pronounced in people under significant stress, which makes sense given the cortisol-lowering mechanism. If your cortisol is already normal, the benefit may be smaller.

Tongkat ali (Eurycoma longifolia) has shown promise in moderately stressed adults. One trial found that daily supplementation reduced cortisol by about 16% and increased testosterone by about 37% over four weeks.²³ The evidence base is smaller than for ashwagandha, and the study used self-reported stress as an inclusion criterion, so how well these results generalize to less-stressed people is unclear.

Phosphatidylserine (PS) works more specifically on the cortisol side. Supplementation with PS blunted the cortisol spike caused by exercise, with one study reporting roughly 35-39% lower peak cortisol after exercise compared to placebo, alongside a significantly improved testosterone-to-cortisol ratio.²⁴ Earlier research found that 800 mg daily for ten days significantly blunted both the ACTH and cortisol response to physical stress.²⁵ Even lower doses in the 50-75 mg range showed a similar blunting effect.²⁶ PS is most useful for people who train frequently and want to limit exercise-induced cortisol elevations rather than as a general testosterone booster.

Body Fat, Alcohol, and Environmental Chemicals

Excess body fat contributes to lower testosterone through a specific mechanism: fat tissue contains an enzyme called aromatase that converts testosterone into estradiol, a form of estrogen. As body fat increases, more testosterone gets converted, which favors further fat accumulation in a self-reinforcing cycle.²⁷ Losing excess fat, particularly visceral fat around the midsection, can meaningfully improve testosterone levels for men who are overweight. This is one area where the effect size from a lifestyle change can be substantial rather than modest.

Alcohol is another factor that works against you on both fronts. Heavy drinking directly damages the Leydig cells in the testes that produce testosterone, leading to reduced levels.²⁸ Alcohol also raises cortisol acutely and disrupts sleep architecture. Occasional moderate drinking is unlikely to have lasting hormonal effects, but regular heavy consumption is one of the more reliable ways to push both hormones in the wrong direction at the same time.

Environmental exposures deserve a mention because they represent a factor many people never consider. Phthalates, chemicals found in plastics, personal care products, and food packaging, have been associated with lower testosterone levels in men. Data from a large national survey found that in men aged 20 to 39, low-molecular-weight phthalate exposure was associated with lower total, free, and bioavailable testosterone. In men over 60, high-molecular-weight phthalates (a category that includes the widely used plasticizer DEHP) were associated with lower testosterone as well, with each doubling of DEHP metabolite concentration linked to roughly an 8% drop in total testosterone.²⁹ You cannot eliminate phthalate exposure entirely, but reducing use of plastic food containers, especially when heating food, and choosing fragrance-free personal care products can lower your exposure.

What Bright Light Does and Does Not Do

You may have seen claims that morning bright light exposure boosts testosterone. The actual research tells a less exciting story. A study examining the effects of bright light exposure on hormonal rhythms found that it shifted the timing of cortisol’s daily peak earlier but did not change cortisol’s average level or peak concentration. Testosterone and prolactin showed no obvious modification at all.³⁰ Morning sunlight is still valuable for anchoring your circadian rhythm, which supports healthy sleep timing, which in turn keeps cortisol’s daily pattern on track. But the mechanism is indirect. Light fixes your clock; it does not directly dial up testosterone or dial down cortisol.

The Dual-Hormone Hypothesis and Why Context Matters

Researchers have proposed a “dual-hormone hypothesis” suggesting that testosterone only influences behavior like assertiveness and risk-taking when cortisol is low. The idea is appealing because it would mean that high cortisol essentially mutes the effects of testosterone. A large meta-analysis covering over 8,500 participants tested this idea and found only marginal support. The interaction between testosterone and cortisol on status-relevant behavior was statistically significant but the effect was very small.³¹

This finding is worth knowing because it tempers one of the more dramatic claims in the self-optimization space: that lowering cortisol will “unlock” the effects of whatever testosterone you already have. The hormones do interact, and chronic cortisol elevation genuinely suppresses testosterone production as covered above. But the idea that cortisol acts as a master switch that blocks testosterone’s downstream effects in your body and brain is not well supported by the pooled data. Improving your cortisol profile is still worth pursuing for sleep, mood, body composition, and cardiovascular health. Just don’t expect it to transform how you feel or perform in the way some marketing copy implies.

Putting It All Together Without Overthinking It

The interventions with the most evidence, roughly ranked by how much they tend to move the needle in people who have room for improvement:

Fix your sleep: Prioritize consistent timing and sufficient duration. This addresses elevated evening cortisol and supports healthy testosterone rhythms.
Lift heavy things: Resistance training produces acute testosterone spikes and, over time, improves body composition, which has its own hormonal benefits. Avoid chronic overtraining by building in recovery.
Eat enough, including carbs: Severe caloric restriction and very-low-carb diets both push cortisol up and testosterone down. If you’re dieting, keep the deficit moderate and keep some carbohydrates in the plan.
Lose excess body fat: The aromatase pathway in fat tissue directly converts testosterone to estrogen. This is one of the larger effect sizes available from a lifestyle change.
Manage stress actively: Mindfulness, breathing exercises, or even just consistent leisure activities can modestly lower cortisol over weeks.
Limit alcohol: Heavy drinking hits both hormones and disrupts sleep.
Consider ashwagandha: If you’re under significant stress, the evidence for cortisol reduction and modest testosterone increases is reasonably strong. Tongkat ali and phosphatidylserine have smaller evidence bases but show promise in specific contexts.
Reduce phthalate exposure: Swap plastic food containers for glass or steel, especially for hot food, and check personal care products for added fragrance.

None of these interventions works in isolation as well as several of them work together. The hormonal systems involved respond to your overall pattern of sleep, activity, nutrition, and stress. Getting three or four of these factors consistently right will do more than obsessing over any single one.