Men's Fertility: Evidence-Based Nutrition Strategies to Start 3 Months Before You're Ready to Conceive
When most couples start thinking about fertility, the conversation centers almost entirely on the woman. Supplements, cycle tracking, labs, lifestyle...it almost always lands in her lap. But male factor infertility or subfertility contributes to roughly half of all cases where conception is taking longer than expected. And the good news is that the male side of the equation is highly responsive to intervention, because sperm is not static.
In fact, sperm only takes about 74 days to fully develop from stem cell to mature spermatozoon, plus additional time for final maturation and transit. For this reason, I like to implement some very specific shifts for male partners at least 3 months in advance of trying to conceive. This post covers the nutrients with the strongest evidence behind them, specific food sources, and supplementation amounts where food alone is unlikely to get you there.
TLDR: If you want to skip ahead, this is my short list of supplements that cover the recommendations in this post.
Male fertility is assessed through a semen analysis, which looks at count, motility, and morphology. A fourth factor, DNA fragmentation, is not always tested routinely but is increasingly recognized as clinically relevant, particularly in unexplained infertility and recurrent pregnancy loss. In fact, when we were trying to conceive our third baby, I had my husband do an advanced sperm analysis through Legacy Health that looked at all of these markers including DNA fragmentation.
Oxidative stress is the underlying driver of all four of these parameters going in the wrong direction. Sperm are uniquely vulnerable to oxidative damage because they have high concentrations of polyunsaturated fatty acids in their membranes and very limited antioxidant capacity of their own. This is why the nutritional framework for male fertility is heavily antioxidant-focused.
Why His Health Affects More Than Just Conception
The conversation around male fertility almost always stops at "can we conceive." But emerging research is making a compelling case that the quality of sperm, not just the quantity, has downstream effects on the pregnancy itself.
Sperm DNA fragmentation is the clearest example. When sperm DNA is damaged or fragmented, fertilization can still occur. The egg has repair mechanisms specifically designed to correct sperm DNA damage after fertilization. But those mechanisms have limits, and when fragmentation is high, the embryo may develop with unresolved DNA errors. This is associated with higher rates of implantation failure, early miscarriage, and recurrent pregnancy loss. A 2019 meta-analysis in Human Reproduction Update found that high sperm DNA fragmentation was significantly associated with increased miscarriage risk in both natural conception and IVF cycles.
Placental development is another area where paternal genetics play a role that most people do not realize. Roughly half of the placenta is genetically paternal in origin. The trophoblast cells that invade the uterine wall and establish blood flow to the growing fetus carry paternal DNA, and the maternal immune system must tolerate those cells for the pregnancy to proceed normally. Research has suggested that poor paternal epigenetic programming which can be influenced by oxidative stress, nutrient deficiencies, and lifestyle, may contribute to suboptimal placental development and function.
Hyperemesis gravidarum and severe morning sickness is where the research gets particularly interesting. A study published in BJOG found that hyperemesis gravidarum (HG), the severe form of pregnancy nausea and vomiting, was significantly more common in pregnancies conceived with a new partner compared to a second pregnancy with the same partner. The prevailing hypothesis involves the maternal immune response to paternal antigens. The idea is that the mother's immune system mounts a stronger response to foreign paternal proteins she has not been previously exposed to, and that this immune response contributes to the severity of nausea. All of this to say, morning sickness severity may have a paternal component that has nothing to do with the woman.
Preeclampsia follows a similar pattern. The incidence of preeclampsia is higher in first pregnancies and in pregnancies with a new partner, which again points toward a paternal immune tolerance mechanism. Studies have found associations between paternal factors including sperm DNA quality and oxidative stress markers and risk of preeclampsia, though this is an area where research is still developing.
The practical implication of all of this is the same as the rest of this post: his preparation matters, it matters early, and it matters beyond just whether a pregnancy occurs. A man going into conception with high oxidative stress, low antioxidant status, and elevated sperm DNA fragmentation is contributing to the environment in which that embryo develops and that pregnancy is sustained, not just to whether the sperm reaches the egg.
What I find so hopeful in the world of fertility is that there is SO much we can do from a diet, lifestyle, and nutritional perspective and when it comes to the male role, we can make a big impact in a relatively short amount of time.
Nutrients of Focus for Male Fertility
CoQ10
Coenzyme Q10 is a fat-soluble antioxidant and a critical component of mitochondrial energy production. Sperm motility is almost entirely mitochondria-dependent, in fact the midpiece of the sperm tail is packed with mitochondria specifically to generate the energy needed for forward progression.
Seminal plasma CoQ10 levels correlate directly with sperm count and motility in multiple studies. A 2019 meta-analysis in the Journal of Urology found that CoQ10 supplementation significantly improved sperm concentration, motility, and morphology compared to placebo. The ubiquinol form (the reduced, active form) is better absorbed than ubiquinone, particularly in men over 35 or those with known absorption challenges.
Food sources: organ meats (liver is the highest), beef, pork, sardines, and mackerel provide meaningful amounts.
Supplementation: 200–400mg daily of ubiquinol is the range supported by the fertility literature.
L-Carnitine and Acetyl-L-Carnitine
The epididymis, this is where sperm mature and gain motility after leaving the testes, is one of the highest carnitine-concentrated tissues in the body. Carnitine is essential for fatty acid transport into mitochondria for energy, and it plays a direct structural and functional role in sperm maturation. Studies show that men with low motility tend to have lower epididymal carnitine concentrations, and supplementation with L-carnitine or a combination of L-carnitine and acetyl-L-carnitine has shown improvements in motility and, in some trials, pregnancy rates.
Food sources: red meat is the primary dietary source, with beef providing approximately 56–162mg per 100g serving. Pork, lamb, and dairy also contribute.
Supplementation: 1–3g daily of L-carnitine, or a combination formula with acetyl-L-carnitine (which crosses into the central nervous system and may have additional antioxidant effects), is the range used in research.
Selenium
Selenium is incorporated into a specific protein called selenoprotein P, which is highly expressed in the testes and plays a structural role in the development of the sperm flagellum, also known as the tail. Without adequate selenium, sperm can develop structural defects that impair motility. Selenium also functions as a cofactor for glutathione peroxidase, one of the body's primary antioxidant enzymes, meaning it provides both direct structural support and broader antioxidant protection to developing sperm.
A 2011 randomized controlled trial published in Andrologia found significant improvements in motility and morphology in subfertile men supplemented with selenium and vitamin E together.
Food sources: Brazil nuts are the most concentrated source by far: just 1–2 Brazil nuts daily provides the 55–200mcg therapeutic range. Tuna, sardines, beef, turkey, and eggs are solid secondary sources.
Supplementation: 100–200mcg daily of selenomethionine, this is the form best supported for bioavailability.
Zinc
Zinc is one of the highest-concentration minerals in seminal plasma and is essential at multiple points in male reproductive function: testosterone synthesis, sperm development, and sperm-egg binding. Zinc deficiency is associated with hypogonadism and reduced sperm quality across multiple parameters. It also functions as a cofactor for superoxide dismutase, another antioxidant enzyme. Notably, zinc competes with copper for absorption, so supplementation needs to account for that balance.
Food sources: oysters are the most concentrated zinc source available: a single 3oz serving provides well over the daily therapeutic target. Beef, lamb, and pumpkin seeds are strong secondary sources.
Supplementation: 25–45mg daily of zinc bisglycinate or zinc picolinate (chelated forms with better absorption).
Folate (as Methylfolate)
Folate is not just for women! Folate is essential for DNA synthesis and methylation, which are both critical in rapidly dividing cells, including developing sperm. Studies have linked low folate intake with increased sperm DNA fragmentation and reduced sperm concentration. This matters especially for couples dealing with recurrent pregnancy loss, where sperm DNA integrity is an underexplored variable.
Important caveat: the form matters. Standard folic acid requires conversion to the active form 5-MTHF via the MTHFR enzyme. A meaningful percentage of the population carries MTHFR variants that impair this conversion. For men, supplementing with methylfolate directly bypasses this issue.
Food sources: liver (again, this is why it's a superfood!), dark leafy greens, legumes, and asparagus.
Supplementation: 400–800mcg daily of 5-MTHF (methylfolate), with higher intake possibly for men with known MTHFR variants or elevated homocysteine.
Vitamin D
Vitamin D receptors are expressed in the testes and on sperm cells themselves. Low vitamin D status is associated with reduced sperm motility, lower testosterone, and poorer overall semen parameters.
A 2011 study in Human Reproduction found a direct positive correlation between vitamin D levels and sperm motility.
Food sources: fatty fish, liver, egg yolks, mushrooms
Supplementation: 2,000–5,000 IU vitamin D3 daily paired with vitamin K2 (MK-7 form) to direct calcium appropriately. Ideally guided by labs, a 25-OH vitamin D level tells you where you're starting and how aggressively to supplement, I want to see levels between 60-100 in the blood.
Omega-3 Fatty Acids (especially DHA)
Sperm cell membranes are rich in DHA. The fluidity and function of the sperm membrane depends heavily on its fatty acid composition, and DHA specifically supports motility and the acrosome reaction, which is the process by which sperm penetrates the egg. Men with lower sperm count and motility tend to have lower DHA in their sperm membranes compared to fertile men.
Food sources: fatty wild-caught fish (salmon, sardines, mackerel, anchovies) 2–3 times per week.
Supplementation: 1–2g daily of combined EPA/DHA from a high-quality, triglyceride-form fish oil. Look for third-party testing for oxidation, as rancid fish oil is counterproductive to the oxidative stress goal.
Magnesium
Magnesium is involved in over 300 enzymatic reactions in the body and is one of the most commonly depleted minerals in men eating a standard Western diet. In the context of male fertility it operates through several pathways simultaneously, which makes it one of the more clinically useful additions to a preconception protocol even though it rarely gets mentioned alongside the headline nutrients like CoQ10 and zinc.
At the sperm level, a 2025 study published in Reproductive BioMedicine Online found that sperm concentration and total sperm count were significantly higher in men in the highest serum magnesium tertile compared to the lowest, at 20.9 million per ml versus 8.6 million per ml, and total numbers of motile and progressively motile sperm were also higher. Higher serum magnesium was also associated with higher AMH, a marker of testicular reserve, while FSH, LH, and inhibin B were unchanged, suggesting magnesium may influence fertility through mechanisms beyond the standard hormonal axes.
Food sources: pumpkin seeds are the most concentrated whole food source, with a single ounce providing around 150mg. Dark chocolate, almonds, cashews, black beans, avocado, leafy greens, and fatty fish all contribute meaningfully. The challenge is that soil depletion has reduced magnesium content in plant foods over the past several decades, and high stress, alcohol, and excessive sweating all deplete magnesium further, meaning dietary intake alone frequently does not maintain optimal tissue levels in men who are physically active or under chronic stress.
Supplementation: 200–400mg daily of magnesium glycinate is the preferred form for most men. It is chelated to glycine, which improves absorption and avoids the laxative effect of cheaper forms like magnesium oxide. Taken in the evening it also supports sleep quality, which in turn feeds back into testosterone production. Men who are also doing resistance training as part of the protocol have higher magnesium losses through sweat and may benefit from the higher end of that range.
Vitamin E
Vitamin E is a lipid-soluble antioxidant that specifically protects the polyunsaturated fatty acids in sperm membranes from oxidative damage. It works synergistically with selenium and vitamin C. Multiple studies, including the selenium/vitamin E RCT cited above, support its role in improving motility and morphology. Most research uses mixed tocopherols rather than synthetic dl-alpha-tocopherol.
Food sources: sunflower seeds, almonds, hazelnuts, and olive oil.
Supplementation: 400 IU daily of natural mixed tocopherols (d-alpha with gamma and delta tocopherols) if dietary intake is low.
NAC (N-Acetylcysteine)
NAC is a glutathione precursor (the body's master intracellular antioxidant). What makes NAC distinct from the other antioxidants in this protocol is where it works: inside the cell, directly addressing sperm DNA fragmentation and integrity rather than just motility and concentration. It also regenerates vitamin C and E after they have neutralized free radicals, effectively extending the functional lifespan of the rest of the antioxidant stack.
A 2021 meta-analysis in Andrologia found that NAC produced significant improvements in sperm concentration, ejaculate volume, motility, and normal morphology compared to placebo. It is particularly relevant for men with elevated DNA fragmentation or a history of recurrent pregnancy loss.
Food sources: NAC is not found directly in food, but its precursor cysteine comes from high-protein animal foods including eggs, chicken, turkey, and beef. Dietary cysteine supports glutathione synthesis but does not replace supplemental NAC at therapeutic doses.
Supplementation: 600mg daily, the dose used consistently across the fertility RCTs.
Alpha-Lipoic Acid (ALA)
ALA is a mitochondrial cofactor and antioxidant with one property that sets it apart: it is both water and fat soluble, meaning it penetrates cell membranes, the cell interior, and the mitochondria itself. Most antioxidants work in one compartment vs both. ALA works across all of them. It also regenerates vitamins C and E, CoQ10, and glutathione after oxidation, making it a force multiplier for the rest of the nutrients discussed in this article.
A 2024 systematic review and meta-analysis confirmed ALA's ability to reduce seminal reactive oxygen species and improve sperm parameters, noting its unique capacity to penetrate tissues, cells, and mitochondria due to its combined water and lipid solubility. For men with partners who had recurrent pregnancy loss specifically, a clinical trial found that 600mg daily for 80 days attenuated sperm DNA damage and lipid peroxidation while improving total motility and chromatin compaction.
Food sources: organ meats, red meat, broccoli, spinach, Brussels sprouts all provide small amounts
Supplementation: 300–600mg daily.
What I actually recommend to my clients (and have my husband taking)
WeNatal for Him Prenatal
This covers A LOT of ground on the nutrients above, especially antioxidants. What I love is that this can serve as a multivitamin AND a sperm support formula, with solid research backed amounts of nutrients like zinc, CoQ10, Acetyl-l-carnitine, Alpha Lipoic Acid, Selenium and more. There is also a protein powder version to make compliance easy.
Take 3/day with food for best outcomes (can replace a daily multivitamin)
EPA DHA Fish Oil
This is a high quality fish oil in a triglyceride form that provides a meaningful amount of DHA. Take 2/day for best outcomes.
Magnesium Glycinate Powder
This is a chelated magnesium powder, best taken at bed to support deep, restful sleep, testosterone production and stress reduction
Take 1 scoop at bed for best outcomes
Vitamin D + K
This is my current favorite Vitamin D that also provides K2.
Note: the WeNatal Prenatal for him contributes 2000 IU Vitamin D. Standard supplementation range is between 2000-5000 IU. If Vitamin D is not optimal (60-100), take this on top of the prenatal at least 5 days per week.
Take 1 softgel daily or at least 5 days per week
Lifestyle Factors That Undermine Even the Best Protocol
Scrotal temperature
The testes sit outside the body for a reason. Sperm development is temperature-sensitive and proceeds best a few degrees below core body temperature. Laptops on the lap, phones in pockets, saunas and hot tubs, tight underwear, and prolonged sitting all elevate scrotal temperature. Studies show measurable effects on sperm parameters from heat exposure. Loose-fitting underwear (ideally cotton) and avoiding sustained heat exposure are low-cost, evidence-supported interventions for the 3-month prep window.
Alcohol and smoking
These are both independently associated with reduced sperm quality across multiple parameters, with dose-dependent effects. Best is to stop drinking and smoking entirely in the 3 month window, and this includes THC.
Sleep and stress are underrated variables
Testosterone production peaks during sleep, cortisol elevation impairs GnRH pulsatility and downstream testosterone signaling, and chronic stress is associated with reduced semen parameters independent of lifestyle factors.
Blood Sugar Imbalance
Insulin resistance directly impairs testosterone production, and chronically high blood sugar generates inflammatory compounds that accumulate in testicular tissue and drive sperm DNA damage. This is not a diabetes-only concern, the man carrying extra weight around his midsection, crashing after meals, and living on processed food is operating in the same physiological pattern to a lesser degree. Practical priorities: build meals around protein and fat first, cut sugar-sweetened beverages, and add resistance training, which drives glucose into muscle rather than into inflammatory pathways. For men with more significant insulin resistance, a lower carbohydrate approach has the strongest evidence for moving testosterone and metabolic markers in the right direction quickly.
Where to Start
Focus your diet on nutrient-dense animal foods including grassfed beef, fatty fish, eggs, and oysters at least weekly. These foods collectively cover most of the above nutrient targets through diet alone. Pair that with dark leafy greens, Brazil nuts daily, and a high-quality fish oil if fatty fish intake is not consistent.
For supplementation, a men's fertility-specific formula that combines CoQ10, zinc, selenium, methylfolate, and vitamin D in evidence-based forms is a reasonable starting point. Layer in additional CoQ10 as ubiquinol and L-carnitine separately if you want to hit the doses used in the research. I lay out my top formulas for men's fertility in this protocol.
Get a semen analysis done now if you are three months out and have any reason to think there may be an issue. It is a simple, inexpensive test that tells you exactly which parameters need the most attention and allows you to target the protocol accordingly.
References
Mancini A, et al. "Meta-analysis of double-blind placebo controlled trials evaluating the role of coenzyme Q10 on semen parameters." Fertility and Sterility, 2018. https://www.fertstert.org/article/S0015-0282(18)31089-6/fulltext
Adiputra IMT, et al. "Efficacy and Safety of Coenzyme Q10 in Idiopathic Male Infertility: A Systematic Review and Meta-Analysis of Randomized Trials." World Journal of Men's Health, 2025. https://wjmh.org/DOIx.php?id=10.5534%2Fwjmh.250159
Su L, et al. "Effect of Antioxidants on Sperm Quality Parameters in Subfertile Men: A Systematic Review and Network Meta-Analysis." Advances in Nutrition, 2022. https://advances.nutrition.org/article/S2161-8313(22)00078-3/fulltext
Moslemi MK, Tavanbakhsh S. "Selenium-vitamin E supplementation in infertile men: effects on semen parameters and pregnancy rate." International Journal of General Medicine, 2011. https://www.tandfonline.com/doi/full/10.2147/IJGM.S16275
Note: a 2025 systematic review found mixed results — include this for balance.
Harouri H, et al. "Therapeutic Efficacy of Selenium-Vitamin E Co-Supplementation on Male Infertility: A Systematic Review and Meta-Analysis." 2025. https://www.researchgate.net/publication/50395942_Selenium-vitamin_E_supplementation_in_infertile_men_Effects_on_semen_parameters_and_pregnancy_rate
Robinson L, et al. "The effect of sperm DNA fragmentation on miscarriage rates: a systematic review and meta-analysis." Human Reproduction, 2012. https://academic.oup.com/humrep/article-abstract/27/10/2908/749072
Coughlan C, et al. "Sperm DNA fragmentation and recurrent pregnancy loss: a systematic review and meta-analysis." PubMed, 2019. https://pubmed.ncbi.nlm.nih.gov/31056315/
Blomberg Jensen M, et al. "Vitamin D is positively associated with sperm motility and increases intracellular calcium in human spermatozoa." Human Reproduction, 2011. https://academic.oup.com/humrep/article-abstract/26/6/1307/2913983
Dalmaz CA, et al. "Change in paternity: a risk factor for preeclampsia in multiparous women?" ScienceDirect, 1999. https://www.sciencedirect.com/science/article/abs/pii/S0165037899000406
Salas SP, et al. "Paternal Determinants in Preeclampsia." PMC/Frontiers, 2019. https://pubmed.ncbi.nlm.nih.gov/30666213/