Does Drinking Water Increase Semen Volume?
No, there is no evidence that drinking water increases semen volume in men. The most recent and authoritative guideline on male infertility from the AUA/ASRM (2024) does not identify water intake as a factor affecting semen volume 1.
What Actually Affects Semen Volume
The 2024 AUA/ASRM guideline systematically reviewed lifestyle and environmental factors that impact male fertility parameters 1. Notably absent from their comprehensive analysis is any mention of water or hydration status affecting semen volume. The factors they did identify as affecting semen volume include:
Documented Factors That Reduce Semen Volume:
- Alcohol consumption: Drinkers have slightly lower semen volume, though this effect is modest 1
- Finasteride 5 mg/day: Associated with reduced semen volume (the 1 mg/day dose has inconclusive data) 1
- Occupational exposure to oil and natural gas extraction: Reduces semen volume 1
- Stress: No association with semen volume was found 1
Normal Semen Volume Parameters:
- Normal ejaculate volume ranges between 1.5 and 5.0 mL 1
- Low ejaculate volume (<1.5 mL) suggests ejaculatory duct obstruction, retrograde ejaculation, hypogonadism, or congenital bilateral absence of the vas deferentia—not dehydration 1
Why Water Intake Is Not a Factor
The comprehensive 2024 guideline examined numerous lifestyle factors including diet, caffeine, alcohol, smoking, stress, and environmental exposures 1. If water intake had a clinically meaningful effect on semen volume, it would have been identified in their systematic review. The absence of this finding is telling.
Additionally, the guideline notes that poor diet results in reduced fertility 1, and multiple studies show that healthy dietary patterns (Mediterranean, DASH, prudent diets) improve sperm concentration, total sperm count, and progressive motility 2. However, none of these studies identified hydration or water intake as an independent factor.
What Actually Matters for Semen Quality
Instead of focusing on water intake, the evidence supports:
- Healthy dietary patterns: Diets rich in vegetables, fruits, nuts, whole cereals, fish, seafood, and low-fat dairy products are positively associated with sperm quality 3, 4
- Specific nutrients: Selenium, zinc, omega-3 fatty acids, CoQ10, and carnitine supplements have been positively related to sperm quality 3
- Avoiding harmful exposures: Minimize alcohol consumption, avoid anabolic steroids, and reduce exposure to pesticides and environmental toxins 1
Clinical Bottom Line
If a patient presents with low semen volume (<1.5 mL), the appropriate workup includes:
- Post-ejaculatory urinalysis to evaluate for retrograde ejaculation 1
- Hormonal evaluation (testosterone, FSH) if hypogonadism is suspected 1
- Transrectal ultrasonography if ejaculatory duct obstruction is suspected (azoospermic with palpable vasa and low volume) 1
- Physical examination to assess for congenital bilateral absence of vas deferentia 1
Recommending increased water intake to improve semen volume has no evidence base and distracts from addressing actual modifiable factors that affect male fertility.