Condition
Oligospermia
Oligospermia is a low sperm count, a common contributor to male infertility that can stem from hormone imbalances, varicocele, infections, heat, or oxidative stress. The evidence is strongest for L-carnitine, where research in 338 men found fertility improved, while tribulus showed limited signs of better erections. Those studies were small to moderate in size, and the tribulus findings concern erections rather than sperm count itself.
Sources: PMID 37686709; PMID 30253697
- Supplements studied
- 4
- Graded outcomes
- 4
- Trials
- 3
- People studied
- 862
Evidence by supplement
- Strong
- Moderate
- Limited
- Very limited
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Fertility Moderate Improvement | Improves (the measure goes up) | Moderate effect | 338 people | |||
| Seminal Motility | Improves (the measure goes up) | 1 study | 244 people | |||
Studies that measured seminal motility | ||||||
| Sperm Count | Improves (the measure goes up) | 693 people | ||||
Ashwagandha
- Luteinizing Hormone: improves
- Testosterone: improves
- Sperm Quality: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Luteinizing Hormone Small Increase | Improves (the measure goes up) | Small effect | 46 people | |||
| Testosterone | Improves (the measure goes up) | 5 studies | 46 people | |||
Studies that measured testosterone
| ||||||
| Sperm Quality | Improves (the measure goes up) | 1 study | 46 people | |||
| Seminal Motility | Improves (the measure goes up) | 46 people | ||||
| Sperm Count | Improves (the measure goes up) | 46 people | ||||
Shilajit
- Follicle-Stimulating Hormone: improves
- Oxidative Stress Biomarkers: changes; see studies
- Luteinizing Hormone: improves
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Follicle-Stimulating Hormone Small Increase | Improves (the measure goes up) | Small effect | 60 people | |||
| Oxidative Stress Biomarkers | Changes; see studies | 1 study | 60 people | |||
Studies that measured oxidative stress biomarkers | ||||||
| Luteinizing Hormone | Improves (the measure goes up) | 60 people | ||||
| Sperm Quality | Improves (the measure goes up) | 60 people | ||||
| Testosterone | Improves (the measure goes up) | 60 people | ||||
Key findings
- FertilityImproves (the measure goes up)
- ErectionsImproves (the measure goes up)
- Luteinizing HormoneImproves (the measure goes up)
The Oligospermia (Low Sperm Count) protocol
2 primary supplements · 7 supporting supplements
- L-Carnitine2–3 g daily (often as acetyl-L-carnitine or L-carnitine combined)
- Coenzyme Q10 (CoQ10)200–400 mg daily
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Studies cited
100 studies from PubMed
- Effects of Withania somnifera supplementation on cognitive function: A systematic review and meta-analysis
- Effects of Ashwagandha (Withania somnifera) Supplementation on Exercise Performance: A Systematic Review and Meta-Analysis
- Ashwagandha (Withania somnifera) and its withanolides attenuate oxidative and inflammatory signaling in the nervous system
- Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis of randomized controlled trials
- Clinical effects of Ashwagandha (Withania somnifera) root extract on human health: A systematic review of reviews
- A Comprehensive Review on Pharmacological Activity of Withania somnifera (Ashwagandha)
- Effects of Ashwagandha (Withania somnifera) on Testosterone Levels: A Systematic Review and Meta-Analysis
- Ashwagandha (Withania somnifera)-Current Research on the Health-Promoting Activities: A Narrative Review
- Withania somnifera (L.) Dunal: A review of chemical composition and pharmacological activities
- Efficacy of Ashwagandha (Withania somnifera) in Improving Cardiorespiratory Endurance and Recovery in Healthy Athletic Adults: A Systematic Review
- Safety of Ashwagandha Root Extract: A Randomized, Placebo-Controlled, Study in Healthy Volunteers
- Examining the Neuroprotective Effects of Ashwagandha: Brain-Derived Neurotrophic Factor in Rats
- Evaluation of antioxidant potential of Rasayana drugs in healthy human volunteers
- An Overview on Ashwagandha: A Rasayana (Rejuvenator) of Ayurveda
- Effects of Withania somnifera in patients of schizophrenia: A randomized, double blind, placebo controlled pilot trial study
- Adjunctive Use of a Standardized Extract of Withania somnifera (Ashwagandha) to Treat Symptom Exacerbation in Schizophrenia: A Randomized, Double-Blind, Placebo-Controlled Study
- Examining the effect of Withania somnifera supplementation on muscle strength and recovery: a randomized controlled trial
- Exploratory study to evaluate tolerability, safety, and activity of Ashwagandha (Withania somnifera) in healthy volunteers
- Effects of an Aqueous Extract of Withania somnifera on Strength Training Adaptations and Recovery: The STAR Trial
- Effects of eight-week supplementation of Ashwagandha on cardiorespiratory endurance in elite Indian cyclists
- Effects of Ashwagandha ( Withania somnifera) on Physical Performance: Systematic Review and Bayesian Meta-Analysis
- Body Weight Management in Adults Under Chronic Stress Through Treatment With Ashwagandha Root Extract: A Double-Blind, Randomized, Placebo-Controlled Trial
- Does Ashwagandha supplementation have a beneficial effect on the management of anxiety and stress? A systematic review and meta-analysis of randomized controlled trials
- A prospective, randomized double-blind, placebo-controlled study of safety and efficacy of a high-concentration full-spectrum extract of ashwagandha root in reducing stress and anxiety in adults
- Adaptogenic and Anxiolytic Effects of Ashwagandha Root Extract in Healthy Adults: A Double-blind, Randomized, Placebo-controlled Clinical Study
- Efficacy of Withania somnifera on seminal plasma metabolites of infertile males: a proton NMR study at 800 MHz
- Withania somnifera Improves Semen Quality in Stress-Related Male Fertility
- Withania somnifera improves semen quality by regulating reproductive hormone levels and oxidative stress in seminal plasma of infertile males
- Clinical Evaluation of the Spermatogenic Activity of the Root Extract of Ashwagandha (Withania somnifera) in Oligospermic Males: A Pilot Study
- Comparative evaluation of the effects of Withania somnifera with pentoxifylline on the sperm parameters in idiopathic male infertility: A triple-blind randomised clinical trial
- A double-blind, placebo-controlled evaluation of the anxiolytic efficacy ff an ethanolic extract of withania somnifera
- Naturopathic care for anxiety: a randomized controlled trial ISRCTN78958974
- Safety and efficacy of Withania somnifera for anxiety and insomnia: Systematic review and meta-analysis.
- Randomized placebo-controlled adjunctive study of an extract of withania somnifera for cognitive dysfunction in bipolar disorder
- Efficacy and Safety of Ashwagandha (Withania somnifera (L.) Dunal) Root Extract in Improving Memory and Cognitive Functions
- Effect of standardized aqueous extract of Withania somnifera on tests of cognitive and psychomotor performance in healthy human participants
- A Randomized, Double-Blind, Placebo-Controlled, Crossover Study Examining the Hormonal and Vitality Effects of Ashwagandha ( Withania somnifera) in Aging, Overweight Males
- Efficacy of Ashwagandha (Withania somnifera Dunal. Linn.) in the management of psychogenic erectile dysfunction
- Efficacy and Safety of Ashwagandha Root Extract in Subclinical Hypothyroid Patients: A Double-Blind, Randomized Placebo-Controlled Trial
- An investigation into the stress-relieving and pharmacological actions of an ashwagandha (Withania somnifera) extract: A randomized, double-blind, placebo-controlled study
- In vivo effects of Ashwagandha (Withania somnifera) extract on the activation of lymphocytes
- Evaluation of the efficacy of Withania somnifera (Ashwagandha) root extract in patients with obsessive-compulsive disorder: A randomized double-blind placebo-controlled trial
- Effect of Ashwagandha (Withania somnifera) extract on sleep: A systematic review and meta-analysis
- Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Insomnia and Anxiety: A Double-blind, Randomized, Placebo-controlled Study
- Efficacy and Safety of Ashwagandha (Withania somnifera) Root Extract in Improving Sexual Function in Women: A Pilot Study
- A randomized, double blind placebo controlled study of efficacy and tolerability of Withaina somnifera extracts in knee joint pain
- Hypoglycemic, diuretic and hypocholesterolemic effect of winter cherry (Withania somnifera, Dunal) root
- Efficacy of Ashwagandha (Withania somnifera [L.] Dunal) in improving cardiorespiratory endurance in healthy athletic adults
- Effect of Withania somnifera (Ashwagandha) on the development of chemotherapy-induced fatigue and quality of life in breast cancer patients
- L-carnitine ameliorated fasting-induced fatigue, hunger, and metabolic abnormalities in patients with metabolic syndrome: a randomized controlled study
- L-Carnitine's Effect on the Biomarkers of Metabolic Syndrome: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
- Ameliorating hypertension and insulin resistance in subjects at increased cardiovascular risk: effects of acetyl-L-carnitine therapy
- Comparative study to evaluate the effect of l-carnitine plus glimepiride versus glimepiride alone on insulin resistance in type 2 diabetic patients
- Effects of simvastatin and carnitine versus simvastatin on lipoprotein(a) and apoprotein(a) in type 2 diabetes mellitus
- Comparison between orlistat plus l-carnitine and orlistat alone on inflammation parameters in obese diabetic patients
- Effects of combination of sibutramine and L-carnitine compared with sibutramine monotherapy on inflammatory parameters in diabetic patients
- L-Carnitine supplementation reduces oxidized LDL cholesterol in patients with diabetes
- Effect of L-carnitine on plasma glycemic and lipidemic profile in patients with type II diabetes mellitus
- Effect of carnitine-orotate complex on glucose metabolism and fatty liver: a double-blind, placebo-controlled study
- Efficacy and tolerability of combined treatment with L-carnitine and simvastatin in lowering lipoprotein(a) serum levels in patients with type 2 diabetes mellitus
- Blood Pressure and Metabolic Effects of Acetyl-l-Carnitine in Type 2 Diabetes: DIABASI Randomized Controlled Trial
- The effects of oral L-carnitine treatment on blood lipid metabolism and the body fat content in the diabetic patient
- The effect of L-carnitine on plasma lipoprotein(a) levels in hypercholesterolemic patients with type 2 diabetes mellitus
- The effects of L-carnitine supplementation on cardiovascular risk factors in participants with impaired glucose tolerance and diabetes: a systematic review and dose-response meta-analysis.
- Effects of acetyl-L-carnitine and methylcobalamin for diabetic peripheral neuropathy: A multicenter, randomized, double-blind, controlled trial
- Effect of oral L-carnitine administration on insulin sensitivity and lipid profile in type 2 diabetes mellitus patients
- The effects of L-carnitine supplementation on glycemic markers in adults: A systematic review and dose-response meta-analysis.
- L-carnitine improves glucose disposal in type 2 diabetic patients
- Caloric restriction and L-carnitine administration improves insulin sensitivity in patients with impaired glucose metabolism
- Preliminary observations on the use of propionyl-L-carnitine in combination with sildenafil in patients with erectile dysfunction and diabetes
- Acetyl-l-carnitine versus placebo for migraine prophylaxis: A randomized, triple-blind, crossover study
- The effects of magnesium, L-carnitine, and concurrent magnesium-L-carnitine supplementation in migraine prophylaxis
- Effects of carnitine on glucose and lipid metabolic profiles and fertility outcomes in women with polycystic ovary syndrome: A systematic review and meta-analysis.
- Oral carnitine supplementation reduces body weight and insulin resistance in women with polycystic ovary syndrome: a randomized, double-blind, placebo-controlled trial
- Effects of Carnitine Administration on Carotid Intima-media Thickness and Inflammatory Factors in Patients with Polycystic Ovary Syndrome: A Randomized, Double-blind, Placebo-controlled Trial
- Effects of L-carnitine supplementation for women with polycystic ovary syndrome: a systematic review and meta-analysis
- Effect of glycine propionyl-L-carnitine on aerobic and anaerobic exercise performance
- Influence of L-carnitine administration on maximal physical exercise
- Effects of nine weeks L-Carnitine supplementation on exercise performance, anaerobic power, and exercise-induced oxidative stress in resistance-trained males
- l-Carnitine l-tartrate supplementation favorably affects biochemical markers of recovery from physical exertion in middle-aged men and women
- Glycine propionyl-L-carnitine produces enhanced anaerobic work capacity with reduced lactate accumulation in resistance trained males
- Chronic oral ingestion of L-carnitine and carbohydrate increases muscle carnitine content and alters muscle fuel metabolism during exercise in humans
- The effect of oral supplementation with L-carnitine on maximum and submaximum exercise capacity
- Effect of intravenous L-carnitine on carnitine homeostasis and fuel metabolism during exercise in humans
- Effects of prolonged L-carnitine administration on delayed muscle pain and CK release after eccentric effort
- l-Carnitine Supplementation in Older Women. A Pilot Study on Aging Skeletal Muscle Mass and Function
- Effects of L-carnitine L-tartrate supplementation on muscle oxygenation responses to resistance exercise
- The effects of L-carnitine L-tartrate supplementation on hormonal responses to resistance exercise and recovery
- Levocarnitine administration in elderly subjects with rapid muscle fatigue: effect on body composition, lipid profile and fatigue
- Oxidative stress in response to aerobic and anaerobic power testing: influence of exercise training and carnitine supplementation
- Effect of L-carnitine on submaximal exercise metabolism after depletion of muscle glycogen
- Androgenic responses to resistance exercise: effects of feeding and L-carnitine
- Carbohydrate, protein, and fat metabolism during exercise after oral carnitine supplementation in humans
- Effects of four weeks L-carnitine L-tartrate ingestion on substrate utilization during prolonged exercise
- L -Carnitine and the recovery from exhaustive endurance exercise: a randomised, double-blind, placebo-controlled trial
- Effects of carnitine coingested caffeine on carnitine metabolism and endurance capacity in athletes
- Effects of L-carnitine supplementation on physical performance and energy metabolism of endurance-trained athletes: a double-blind crossover field study
- Clinical Effects of L-Carnitine Supplementation on Physical Performance in Healthy Subjects, the Key to Success in Rehabilitation: A Systematic Review and Meta-Analysis from the Rehabilitation Point of View.
- L-Carnitine/Simvastatin Reduces Lipoprotein (a) Levels Compared with Simvastatin Monotherapy: A Randomized Double-Blind Placebo-Controlled Study
- Effect of lysine, vitamin B(6), and carnitine supplementation on the lipid profile of male patients with hypertriglyceridemia: a 12-week, open-label, randomized, placebo-controlled trial