Articles

Research-first writing on sauna, heat, fertility, and men's health. What the evidence actually says, claims examined.

Male Infertility Diagnosis Still Runs on a 1950s Playbook
A fertility workup starts the same way for most men. You get a cup, a room with a chair, and instructions to abstain for two to seven days before producing a sample. The test that comes out of that room descends directly from population studies first run in the 1950s. The categories have been refined and the microscopes improved, but the basic structure of the male infertility workup has barely moved in seven decades.That is not a complaint about fertility clinics. The standard workup catches real problems. The gap is... Read more...
Male Infertility Support Groups Inherited a Model That Doesn’t Fit Men
Barbara Eck Menning started RESOLVE in 1974. She had lived through infertility herself and built the first infertility support organization in the United States around the consciousness-raising circle she knew from the women’s health movement. The format made sense for that moment. It also became the default template for every infertility support group that followed, including groups aimed at men.Most men never show up. When they do, they sit quiet or drop out after a session or two. The standard explanation is stigma. Men get taught not to talk about... Read more...
What Happens When the Heat Stops: Male Factor Infertility Success Stories
Male factor infertility success stories don't always start in a clinic. Some start with a habit inventory, a cooler pair of underwear, and a retest a few months later. Sauna-level heat temporarily lowers sperm count and can worsen morphology (Garolla et al., Human Reproduction, 2013). The effect reverses once the heat exposure stops. One study followed men who gave up regular wet heat and found their semen parameters recovered within months (Shefi et al., Fertility and Sterility, 2007). Sperm production needs the testicles a few degrees below core body temperature,... Read more...
Natural Testosterone Boosters: A Regulatory Accident That Outran the Science
Walk into any supplement store and the testosterone boosters all promise the same things: more energy, more muscle, and a better sex life. The labels lean on tribulus terrestris, D-aspartic acid, fenugreek, and ashwagandha. The clinical trials tell a quieter story. In healthy men, most of these ingredients do not raise testosterone at all.I have spent years reading the trial data behind this category. The products are not worthless, but the mechanism most men assume is happening usually is not.The category was built on two laws and a failed animal... Read more...
The Most Permeable Patch: What a 1971 Skin Study Adds to the Microplastics and Male Fertility Debate
Dermatology mapped the male body's absorption hotspots long before anyone worried about microplastics. In 1971, Howard Maibach and colleagues at the University of California applied the same test compound to different skin sites in human volunteers and measured how much penetrated over time. The scrotum ranked near the top, far above the forearm baseline and higher than the scalp, forehead, and underarm. That study had nothing to do with plastic or fertility. It was pure skin physiology. Fifty-plus years later, that physiology is the part of the plastic exposure conversation... Read more...
You're Probably Overhydrating for the Sauna
Weigh yourself before you step into a hot sauna, then again when you leave. The number drops by less than most men expect, usually somewhere between half a liter and a liter for a 20-minute session. That is one or two glasses of water, not the wholesale fluid loss some hydration guides imply. The advice to preload with a liter, sip constantly, and replace electrolytes like a marathoner does not come from sauna research. It comes from endurance sport, where the losses are five to ten times larger.Men's health content... Read more...
Sauna and Sperm: The Two-Month Delay That Explains the Temporary Drop
Sauna heat lowers sperm count temporarily. The confusing part is timing. A sauna session in February does not change what a semen analysis shows the next morning. It changes what that analysis shows around April. Sperm production runs on a roughly two-month schedule, and most sauna research only makes sense when you read it against that clock.The online summaries skip this part. They list "sauna lowers sperm count" next to "heat is reversible" and leave you to piece together the timeline. Once you see the timeline, the topic stops being... Read more...
Your Sauna Rocks Are a Thermal Battery
A liter of water thrown onto properly heated sauna stones pulls roughly 2.6 megajoules of energy out of the rock. That number explains the whole session. The stones are the thermal battery that stores the stove's output and hands it back to you as radiant heat and steam.Most sauna conversation stops at air temperature and how long you sat inside. That misses the component doing the real work. I have broken enough stones and rebuilt enough stoves to see that stone choice, stone mass, and how you stack the pile... Read more...
Why Labs Add Caffeine to Sperm Samples While a 2,554-Man Study Flagged Cola
An embryologist trying to get a sluggish sperm sample to move will sometimes add caffeine, or a close chemical relative, to the dish. A 2010 study of 2,554 young Danish men found that those who drank more than a liter of cola a day had lower sperm concentration than those who rarely touched it. Both facts are real. They sit in the same literature and point in different directions. The reason they coexist matters more than either one alone.Caffeine in the andrology labCaffeine belongs to a family of compounds called... Read more...
Your Testicles Work the Night Shift
Most fertility advice for men reads like a shopping list. Oysters. Loose underwear. Keep the laptop off your lap. Sleep gets one vague line about getting seven hours, and that line skips over something important.Eight hours lying under covers in a warm room, legs together, is the longest block of controlled temperature your testicles get all day. That nightly environment shapes the conditions sperm production depends on. The research on shift workers, sleep timing, and testosterone points to mechanisms most men never hear about.The nightly cooling windowCore body temperature follows... Read more...