Going without underwear as a male is, for most everyday situations, perfectly fine from a health standpoint. There is no medical requirement to wear underwear, and skipping it can even offer a modest advantage in one area that surprises many men: testicular temperature regulation and sperm production. That said, ditching the extra layer comes with real trade-offs involving skin irritation, mechanical injury risk, and hygiene that are worth understanding before you commit to the commando lifestyle full-time.
Scrotal Temperature and Sperm Health
The testes hang outside the body for a reason. Sperm production works best at temperatures a few degrees below core body temperature, and the scrotum is designed to regulate that cooling. Anything that holds the testes closer to the body and traps heat can interfere with this process. Tight-fitting underwear does exactly that. A study of over 650 men attending a fertility center found that men who primarily wore boxers had roughly 25% higher sperm concentration and 17% higher total sperm count compared to men who wore tighter styles like briefs or bikinis.1PubMed Central. Type of underwear worn and markers of testicular function among men attending a fertility center Those men also had lower levels of follicle-stimulating hormone (FSH), a hormone the brain releases to push the testes harder when sperm production is lagging. The implication is that tight underwear creates enough extra heat to suppress sperm output, and the body compensates by cranking up its hormonal signal.
A broader narrative review of research on garment fit and male fertility confirms the pattern: physiological studies consistently find higher scrotal temperatures in men wearing tighter underwear, and cross-sectional analyses show modest differences in semen quality between brief-wearers and boxer-wearers.2PubMed Central. Garment fit, scrotal thermoregulation, and male fertility outcomes: a narrative review That same review notes, however, that prospective studies have not demonstrated differences in actual pregnancy outcomes. In other words, wearing tight underwear measurably changes sperm numbers and hormone levels, but whether that change is large enough to affect your ability to conceive is less clear.
Going completely without underwear takes the temperature benefit a step further than boxers alone, since there is no fabric layer at all pressing the scrotum against the body. For men who are actively trying to conceive or who have borderline semen parameters, this is one of the simplest environmental changes available. For men with no fertility concerns, the temperature difference is real but probably academic.
The Zipper Problem
The most immediate and visceral risk of going commando is mechanical. Without a fabric barrier between the penis and a trouser zipper, the chance of penile zipper entrapment goes up. This is not a theoretical concern. Emergency departments treat zipper injuries regularly, and while they can happen even when underwear is present, the absence of that protective layer matters. A case report on penile zipper entrapment noted that while people not wearing underwear face greater risk, more than half of documented cases actually occurred in patients who were wearing underwear at the time.3PubMed Central. When zippers attack: the first documented case of penile zipper entrapment requiring emergency circumcision in a resource-limited setting So underwear reduces the risk but does not eliminate it. The takeaway is practical: if you go without underwear and your trousers have a zipper fly, be deliberate when zipping up. Button-fly pants eliminate this concern entirely.
Beyond zippers, there is the matter of general friction and contact with rougher fabrics. Denim seams, coarse wool, and stiff synthetic materials can irritate the glans and shaft over the course of a day, especially during movement. The penile skin, and particularly the glans, is not accustomed to direct contact with outerwear textures. Men who go commando regularly tend to gravitate toward softer fabrics like cotton chinos or joggers for exactly this reason.
Skin Reactions From Direct Fabric Contact
When you wear underwear, it acts as a buffer between your genital skin and whatever dyes, finishes, and chemical treatments are in your outer clothing. Remove that buffer and your most sensitive skin sits directly against the trousers. This matters because textile dyes, particularly reactive dyes used in dark-colored garments, can cause allergic contact dermatitis. A documented case involved a patient who developed dermatitis from reactive dyes in a dark cotton garment and found that the garment needed to be washed at least three times before the allergic reaction stopped occurring.4PubMed. Allergic contact dermatitis associated with reactive dyes in a dark garment: a case report The researchers emphasized that when reactive dyes are not thoroughly rinsed during manufacturing, excess dye retained in the fabric can trigger allergic skin reactions.
Most people never develop a dye allergy, but the groin area is particularly vulnerable to contact irritants because the skin there is thinner, warmer, and often moist. These conditions increase absorption of chemical residues. If you go commando in brand-new, unwashed dark jeans or trousers, you are essentially putting your most absorbent skin in direct contact with whatever chemical residues remain from the dyeing process. Washing new garments before wearing them is always good practice, but it becomes more important when there is no underwear acting as a protective layer.
Formaldehyde-based wrinkle-resistant finishes, commonly applied to dress shirts and slacks, are another potential irritant. These finishes are less concentrated in garments by the time they reach the consumer, but for someone prone to contact sensitivity, direct genital exposure without a fabric barrier could provoke a reaction that underwear would have prevented.
Chafing During Physical Activity
For sedentary or lightly active days, many men find going commando comfortable or even preferable. The problems tend to show up during exercise, manual labor, or any sustained physical activity involving repetitive leg movement. Without underwear, the inner thighs rub directly against each other and against the scrotum, and penile skin rubs against trouser fabric. Over hours, this produces chafing that can range from mild redness to raw, broken skin.
Athletic underwear exists specifically to address this. Compression-style briefs hold everything in place, reduce bounce and friction, and wick moisture away from the skin. Going commando during a long run, a bike ride, or a hike is a recipe for irritation that most men only try once. The scrotal skin in particular is loose and mobile, and without support it folds and creases against itself during movement, creating friction points that can develop into painful sores.
Moisture makes chafing worse. The groin is one of the body’s highest-sweat-output zones, and without an absorbent underwear layer to pull moisture away from the skin surface, sweat accumulates in folds and creates a slippery-then-sticky cycle that accelerates friction damage. Anti-chafing balms and powders help, but they are treating a problem that supportive underwear largely prevents.
Hygiene and What Happens to Your Outer Clothes
Underwear serves as a collection layer. It catches sweat, skin oils, dead skin cells, and trace amounts of fecal bacteria and urinary residue that are normal parts of the genital environment. When you wear underwear, those substances end up in a garment that gets washed after every wearing. When you skip underwear, all of that transfers directly to your trousers or shorts, which most people do not wash after every wear.
Human skin lipids, particularly sebum, are a major component of the oily residue that accumulates in worn clothing. Research on detecting sebum residues in worn garments found a clear relationship between the amount of skin-oil buildup and fabric degradation, with sebum residues accelerating the breakdown of textiles on exposure to environmental factors like ozone.5Textile Research Journal. Perspectives on textile cleanliness – detecting human sebum residues on worn clothing Going commando concentrates these oils in the crotch area of trousers that may go days between washes, potentially shortening the lifespan of the garment and creating lingering odor.
The bacterial angle is worth considering too. The perianal region harbors bacteria that can migrate forward, especially during a physically active day. Underwear provides a contained environment for that migration. Without it, those bacteria transfer to trouser fabric that sits at room temperature in a closet overnight, giving microbes time to multiply in an unwashed environment. For most healthy men this does not cause illness, but it can contribute to persistent odor in clothing and, in rare cases, to skin infections if broken or chafed skin is present.
Sensitivity and Circumcision Status
Whether you are circumcised or uncircumcised changes the experience of going commando. In uncircumcised men, the foreskin covers the glans during normal daily activity, providing its own protective layer. This means the glans is not in direct contact with outer clothing even when underwear is absent, which reduces friction and irritation considerably. Circumcised men do not have this built-in covering, and their glans is directly exposed to whatever fabric they are wearing.
A study measuring fine-touch pressure thresholds across the penis found that the glans of uncircumcised men had significantly lower pressure thresholds (meaning higher sensitivity) than that of circumcised men, even after controlling for variables including the type of underwear worn.6ResearchGate. Fine-touch pressure thresholds in the adult penis The circumcised glans, through constant exposure to clothing, develops a thicker outer layer over time. Going commando accelerates that exposure for circumcised men, since the glans now contacts rougher outer fabrics rather than the softer material of underwear. Whether this results in any perceptible change in sensitivity over a normal lifespan is debated, but the mechanism is real.
For uncircumcised men, going without underwear tends to be more comfortable because the foreskin handles most of the protective work. Some circumcised men find that the glans becomes uncomfortably sensitive when it catches on trouser seams or zippers, especially when transitioning from years of always wearing underwear. This typically diminishes over a few weeks as the skin adjusts, but it is worth knowing about before making the switch.
When Going Commando Makes the Most Sense
Context matters more than a blanket recommendation. Sleeping without underwear is one of the least controversial applications. Nighttime is when the groin area benefits most from ventilation, and the warm, moist environment created by underwear during sleep can promote fungal growth. Men prone to jock itch (tinea cruris) often find that sleeping without underwear, or at least switching to very loose boxers, reduces recurrence. The fungus responsible thrives in warm, dark, humid environments, and removing a tight fabric layer at night disrupts those conditions.
Hot climates and humid conditions are another context where going commando has legitimate comfort advantages. The reduced fabric layer allows better airflow and evaporation, which keeps the groin cooler and drier. Conversely, cold weather tends to make the absence of underwear less pleasant. The extra layer provides insulation, and without it, wind and cold air reach the genitals more directly.
Men with certain skin conditions may benefit from going without underwear in specific situations. Eczema or psoriasis affecting the groin can be aggravated by elastic waistbands, seams, and synthetic fabrics found in many underwear styles. Removing the underwear and wearing loose-fitting, soft-cotton outer pants can reduce the mechanical irritation that triggers flare-ups. However, this needs to be balanced against the contact-dermatitis risk from outer garment dyes discussed earlier.
What About Support During Everyday Life
Some men worry that the testicles need physical support to stay healthy, and that going without underwear allows too much movement. There is no medical evidence that the testicles require external support during normal daily activities. The cremaster muscles and the dartos fascia within the scrotum naturally raise and lower the testes in response to temperature and physical position. Supportive underwear can reduce the sensation of bouncing or pulling during movement, which is a comfort preference, not a health requirement.
The one situation where medical support is genuinely indicated is after scrotal surgery or injury. Post-vasectomy instructions, for instance, typically include wearing supportive briefs or a jock strap for several days to reduce swelling and discomfort. Going commando during surgical recovery from any scrotal procedure is a bad idea, not because of the testes’ general need for support, but because swollen tissue benefits from compression and immobilization.
Varicoceles, enlarged veins within the scrotum that affect a substantial minority of men, can produce a dull aching sensation that worsens with prolonged standing or physical activity. Many men with varicoceles find that supportive underwear reduces this discomfort by limiting how much the affected veins stretch under gravity. Going without underwear in this case is not dangerous, but it can make an already uncomfortable condition harder to ignore throughout the day.
The Effect on Outer Clothing Fit and Appearance
A purely practical concern that rarely comes up in health discussions: underwear shapes the way trousers fit, and removing it changes the visual result. Boxer briefs create a smoother silhouette under slim-fit pants. Without underwear, the natural contours of the genitals may be more visible through thinner fabrics, and seam lines from the trousers can press into skin in ways that create visible outlines. This is a personal and social concern rather than a medical one, but it is one of the main reasons men who try going commando ultimately go back to wearing underwear in certain contexts, particularly at work or formal settings.
Sweat staining is another cosmetic issue. The groin produces sweat throughout the day, and without an absorbent underwear layer to capture it, that moisture transfers directly to trouser fabric. Light-colored khakis and dress pants can develop visible sweat marks in the crotch area that would not appear if underwear had absorbed the moisture first. Dark fabrics hide this better, but the moisture still accumulates in the garment.