Cool Beans Underwear® is an anatomy-engineered underwear structure designed to support male physiology in everyday life - especially in long seated, heat-exposed, high-sweat, and high-friction conditions.
It’s built for men who want support across:
- Daily comfort + movement
- Heat management + breathability
- Testosterone health + vitality
- Erections + sexual function
- Fertility and sperm health (as one part of the bigger picture)
- Post-operative and pelvic comfort support (where clinically appropriate)
Most men’s underwear holds everything close to the body and between the thighs, which can:
- Increase trapped heat and sweat
- Increase skin-on-skin friction
- Increase “drag” on the scrotum during movement
- Reduce natural positioning comfort for many men
Cool Beans is different. It uses a structural pouch + supportive body design to:
Reduce thigh insulation + core heat absorption
- Positions the scrotum forward and away from the thighs
- Helps reduce the “sandwich effect” where thighs trap heat and moisture
Support natural scrotal movement (retract + relax)
- The scrotum is designed to move - retracting when cold/stressed and relaxing when warm
- Cool Beans supports that physiological movement, without leaving everything unsupported or excessively hanging
Reduce friction + improve daily comfort
- Less skin-on-skin contact
- Less sweat pooling
- Better day-long comfort for walking, sitting, training, and working
Why heat matters: how testes work (and why they sit outside the body)
Your testes do two major jobs:
- Produce testosterone (primarily via Leydig cells)
- Produce sperm (within the seminiferous tubules, supported by Sertoli cells)
Sperm production is androgen-dependent (requires hormonal signalling, including testosterone, plus FSH/LH pathways). [Frontiers+1]
Testes are external for a reason
Human testes are normally maintained around 2–4°C cooler than core body temperature to support optimal cellular function and sperm development. [PubMed+1]
Your body achieves this through thermoregulation systems such as:
- Scrotal skin heat exchange with the environment
- Muscle reflexes (dartos/cremaster) that adjust positioning
- Blood-flow heat exchange via the pampiniform plexus [ScienceDirect+1]
When the scrotal environment is repeatedly exposed to excess heat - especially during prolonged sitting, driving, or heat-exposed work - research shows spermatogenesis can be disrupted and sperm DNA integrity can worsen (higher DNA fragmentation). [PubMed+2]
Heat stress is also described in the scientific literature as impairing testicular steroidogenesis (the cellular processes involved in testosterone production).
Everyday heat exposure is real (and it’s common)
Modern life stacks the deck:
- Long hours sitting (office chairs, trucks, commuting, control rooms)
- Driving + seat contact
- High-heat workplaces
- Tight, non-breathable or poorly designed underwear
- Reduced airflow and increased sweat
Research shows scrotal skin temperature can rise up to ~3°C within 20 minutes of sitting on common chairs during seated activities, including office sitting and driving contexts. [Wiley Online Library+2]
And heat stress to the testes has been associated with measurable negative changes in sperm parameters in clinical research contexts. [PMC+1]
Cool Beans is designed to support anatomy and reduce compounding heat exposure through structural repositioning and ventilation.
- Internal testing: We have conducted internal scrotal skin temperature measurements comparing Cool Beans with other common underwear styles under the same test conditions. In our internal measurements, Cool Beans recorded lower scrotal skin temperature than the other styles we tested. (Results vary between individuals and depend on clothing, activity, and environment.)
- Real-world experience: Some customers report they can feel cooler airflow on scrotal skin when wearing Cool Beans under their usual clothing choices. Individual experience varies.
Sperm DNA fragmentation: the male factor that's often missed
What it is
- DNA fragmentation refers to breaks or instability in sperm DNA - something a standard semen analysis doesn’t directly measure. [PMC+1]
- It can be influenced by factors including heat exposure, oxidative stress, and varicocele (among others). [ASRM+2]
- Major guidelines state sperm DNA fragmentation testing is not recommended in the initial evaluation of infertility - so it’s often introduced later in the journey. [ASRM]
When it’s commonly considered
Guidelines and clinical practice discussions increasingly point to sperm DNA fragmentation testing being most useful in specific scenarios such as:
- Recurrent pregnancy loss (recurrent miscarriage) [ASRM+1]
- Repeated IVF failure / recurrent failure to achieve pregnancy (clinic practices vary) [PMC+1]
- Male risk factors (e.g., varicocele, lifestyle/environmental exposures) [PMC+1]
Why DNA fragmentation matters: for conception, pregnancy and beyond
- Miscarriage: A large meta-analysis found significantly higher miscarriage rates when sperm DNA damage is high. [OUP Academic]
- Higher sperm DNA damage has been associated in the literature with poorer reproductive outcomes and pregnancy loss signals (evidence quality varies by test type and scenario).
- IVF outcomes: Systematic reviews/meta-analyses report a detrimental association between sperm DNA damage and assisted reproduction outcomes (noting variation by test type and treatment). [PMC]
- Offspring outcomes: Evidence is still evolving, but some studies in ART populations report associations between higher sperm DNA fragmentation and outcomes such as birth weight, alongside miscarriage risk. [Nature]
DNA fragmentation is not “the” cause of miscarriage - miscarriage is multifactorial - but it is a meaningful male-factor signal that can be overlooked when the focus stays on the woman only. [ASRM+1]
If you've experienced the following
- Recurrent miscarriage, or
- Repeated IVF failure,
ask your clinic whether sperm DNA fragmentation testing should be considered in your case. [ASRM+1]
Testicular function sits upstream of multiple systems.
Testosterone is clinically linked with:
- Sexual function and erections (low testosterone is associated with sexual symptoms including ED in clinical guidance) [OUP Academic+1]
- Mood, motivation, energy, cognition (symptoms of testosterone deficiency can include low energy, depressed mood, reduced initiative) [OUP Academic+1]
- Metabolic health (low testosterone is associated with higher cardiometabolic risk patterns; evidence is strongest for association, and treatment evidence varies by population) [PubMed+2]
Erections are also a health signal
Erectile dysfunction can be an early marker of cardiovascular risk in clinical consensus guidance - often prompting clinicians to assess broader cardiometabolic health. [OUP Academic]
Mental health + PTSD
Hormones, sleep, stress physiology, and mental health are tightly linked. Research exploring testosterone and PTSD risk/symptom profiles is active and nuanced (it does not prove simple cause → effect), but it reinforces that men’s health needs to be treated as a whole-system issue. [PMC+1]
Fertility + offspring health
Sperm health is more than “can you conceive”- it can reflect broader biological stress.
- Higher sperm DNA fragmentation is associated with poorer reproductive outcomes in assisted reproduction (IVF/ICSI) meta-analyses. [PubMed]
- Higher sperm DNA damage is associated with increased miscarriage risk in meta-analysis data. [PubMed]
- Paternal age is strongly associated with increased de novo mutations in offspring (genome sequencing evidence). [Nature+1]
This is about the future you’re building—not just a single fertility outcome.
We engineered Cool Beans so men don’t have to “put up with” discomfort to get the benefits.
Designed for real anatomy
- Supportive waistband + supportive body structure (pelvis comfort)
- A pouch designed to keep the scrotum positioned away from the thighs
- A structure that supports natural retract/relax movement without excessive drag
3 pouch sizes (because men aren’t one shape)
Cool Beans comes with three pouch sizes to accommodate different anatomy and comfort preferences:
- Quokka
- Koala
- Wombat
Result (what men typically report):
- Less rubbing and chafing
- Less sweat pooling
- Better day-long positioning comfort (sitting, walking, training)
A new anatomical sensation can take a moment for your nervous system to map.
- Most men take ~3–5 days to fully adapt to the new sensation
- This is a normal neurological adjustment to a different support/positioning experience
- After that, it usually feels “normal”… just better supported
Tip: If you’re between sizes, we recommend going with the larger size.
FAQs
Sperm development takes time (often discussed in ~months, not days). If you’re making changes for fertility, think in multi-month timeframes and work alongside your clinician. Our recommendation is to wear Cool Beans for 4 months prior beginning your conception journey for optimal sperm optimisation.
Medical note
Cool Beans Underwear® supports anatomy and heat management. It is not a substitute for medical care. If you have pain, swelling, fertility concerns, erectile dysfunction, or symptoms of low testosterone, speak with a qualified healthcare professional.
Scientific References
- Australian Register of Therapeutic Goods (ARTG). Cool Beans Underwear® listing (ARTG 379655). [TGA ARTG entry]
- Durairajanayagam, D., et al. Review of heat exposure and male fertility impacts. [ScienceDirect]
- Rao, M., et al. Human scrotal hyperthermia study and impacts on sperm parameters. [PMC]
- Jung, A., et al. Seated activities / driving contexts and scrotal heat exposure. [Wiley Online Library]
- Oduwole, O. O., & colleagues. FSH/LH/testosterone roles in spermatogenesis (reviews). [Frontiers] [PubMed]
- Kloner, R. A., et al. Princeton IV Consensus: ED as a cardiovascular risk marker. [OUP Academic]
- Walther, A., et al. Testosterone treatment and depressive symptoms meta-analysis (context on hormone–mood linkage). [JAMA Network]
- Robinson, L., et al. Sperm DNA fragmentation and miscarriage risk meta-analysis. [PubMed]
- Simon, L., et al. Sperm DNA damage and IVF/ICSI outcomes meta-analysis. [PubMed]
- Kong, A., et al. Paternal age and de novo mutations (Nature). [Nature]
- American Urological Association (UrologyHealth.org). Varicocele conservative management (scrotal support). [UrologyHealth.org]