Is Testogen Ultimate Worth It? My Review After Using The New Formula (2026)

After 40, testosterone does not just slow down. It starts working against you.

Energy drops. Muscle gets harder to build.

Body fat settles in places it never used to. The drive that used to carry you through tough days starts to fade.

Testogen has been around for years as a natural testosterone booster. They have just released a completely overhauled formula called Testogen Ultimate: more ingredients, higher doses, and premium forms across the board.

I have gone through every ingredient in detail. Here is what you need to know.

Pros

• 13 ingredients at clinical doses with no proprietary blends
• KSM-66 Ashwagandha reduces cortisol, a key testosterone killer in men over 40
• 4,000 IU Vitamin D3, the dose used in testosterone research
• Premium chelated minerals for superior absorption
• Fully transparent label with no fillers
• Vitamin K2 MK-7 included to work synergistically with D3
• Copper included to offset long-term zinc supplementation

Cons

• Only available online, not in stores
• Four capsules per day requires daily consistency
• Premium formula comes at a higher price point than budget alternatives
• Results take time, typically 8 to 12 weeks for full effect

What Is Testogen Ultimate

Testogen Ultimate is the latest version of Testogen, a natural testosterone booster made by Health Nutrition Limited, a UK-based supplement company. It is designed specifically for men experiencing the effects of declining testosterone, particularly those over 40.

The formula targets testosterone from multiple angles: stimulating natural production, freeing up bound testosterone in the bloodstream, and reducing the hormones that suppress it.

The name "Ultimate" reflects the depth of the reformulation. This is not a minor ingredient swap or a marketing rebrand.

Testogen Ultimate adds four entirely new ingredients, increases dosages significantly across the board, and upgrades every ingredient to a premium form. Health Nutrition Limited have positioned it as their flagship formula for men in their 40s and beyond.

Testogen Ultimate Ingredients

D-Aspartic Acid (2,025 mg)

D-aspartic acid is an amino acid that signals the brain to release more luteinizing hormone. Luteinizing hormone tells the testes to produce testosterone.

Clinical studies showing meaningful testosterone increases used doses of 2,000 mg or more. ^[1] One study found men with lower testosterone saw a 50% increase in levels after 12 days at this dose. ^[2]

At 2,025 mg, Testogen Ultimate exceeds most competitors who use 1,500 mg or less.

KSM-66 Ashwagandha (200 mg)

KSM-66 is the most studied form of ashwagandha available, using the full-spectrum root extract for consistent potency in every capsule. Most competitors use generic ashwagandha with no standardization guarantee, meaning potency varies batch to batch.

Clinical trials show KSM-66 reduces cortisol by up to 27.9%. ^[3] Cortisol and testosterone work against each other in a direct trade-off.

When chronic stress keeps cortisol elevated, the body deprioritizes testosterone production. This is one of the most significant and overlooked drivers of testosterone decline in men over 40.

Korean Ginseng (100 mg)

This extract is standardized to 5% ginsenosides, guaranteeing consistent active compound levels in every capsule. Generic ginseng without standardization can vary widely in potency between batches.

Research shows Korean ginseng can increase testosterone and significantly improve symptoms of low sexual function. ^[4] It also supports energy, stamina, and cognitive performance.

These are three areas men over 40 typically feel declining first. The dose here is more than double what the original formula contained.

Fenugreek Extract (100 mg)

Fenugreek works through two separate mechanisms to support testosterone. It inhibits both aromatase and 5-alpha reductase, two enzymes that convert testosterone into other hormones.

A study specifically on men aged 43 to 75 found fenugreek supplementation produced meaningful testosterone increases and improved libido. ^[5] The dual-pathway action makes it particularly relevant for older men where aromatase and 5-alpha reductase activity tend to increase.

Stinging Nettle (80 mg)

Testogen Ultimate uses a 10:1 root extract, delivering ten times the active compounds of standard nettle root per milligram. This is double the concentration of the 4:1 extract used in the original formula.

The key compounds are lignans, which bind to sex hormone-binding globulin (SHBG). SHBG locks up testosterone in the bloodstream, making it unavailable for use.

Research shows nettle lignans can reduce SHBG binding by up to 67%, releasing more free, usable testosterone. ^[6] For men over 40, where SHBG levels tend to rise naturally, this is a particularly valuable mechanism.

Vitamin D3 (100 mcg / 4,000 IU)

Vitamin D3 functions as a hormone precursor in the body. Men with low vitamin D consistently show lower testosterone across clinical studies, and deficiency is extremely common in men over 40.

A year-long study found men who corrected their vitamin D deficiency saw a 25% increase in total testosterone. ^[7] At 4,000 IU, Testogen Ultimate uses the dose from that research.

The original formula contained only 800 IU. This upgrade represents a fivefold increase to reach clinical relevance.

Vitamin K2 (90 mcg MK-7)

K2 as MK-7 stays active in the body for up to 72 hours, compared to just a few hours for the cheaper MK-4 form used by most brands. It works in direct partnership with Vitamin D3 and is new to this formula.

K2 supports the hormonal pathway that D3 activates and ensures calcium is directed to the right places. Including K2 alongside high-dose D3 is a marker of a formula designed with real biochemistry in mind.

Zinc (25 mg)

Testogen Ultimate uses zinc monomethionine, a chelated form that absorbs significantly better than the zinc oxide found in most supplements. Zinc is one of the most critical minerals for testosterone production.

A study found older men supplementing with zinc saw close to a 50% increase in testosterone over six months. ^[8] Zinc deficiency directly and rapidly suppresses testosterone output.

At 25 mg, this is more than double the 10 mg in the original formula.

Magnesium (80 mg)

Testogen Ultimate uses a blend of bisglycinate and citrate forms, both of which absorb far better than the magnesium oxide found in most products. Magnesium oxide has as low as 4% bioavailability.

Magnesium supports over 300 enzymatic processes including testosterone production. Research shows magnesium supplementation can increase both free and total testosterone levels in active men.

Many men over 40 are deficient without knowing it, as dietary intake is often insufficient and stress further depletes magnesium stores. This is a new addition to the Testogen Ultimate formula.

Vitamin B6 (8 mg)

B6 here is in the P5P form (Pyridoxal 5-Phosphate), the active coenzyme form the body can use directly. Standard pyridoxine HCl used by most brands requires liver conversion before it becomes useful.

P5P supports androgen receptor activity and healthy estrogen metabolism. Both are relevant for men trying to maintain testosterone balance as they age.

BioPerine (7 mg)

BioPerine is the patented piperine extract standardized to 95% piperine. It inhibits the metabolic pathways the body uses to break down nutrients before they reach circulation, increasing bioavailability across the formula.

In practice, this means every other ingredient absorbs more effectively. Research shows piperine can significantly improve nutrient absorption in active individuals. ^[9]

Boron (5 mg)

Testogen Ultimate uses boron bisglycinate, a chelated form with better absorption than the boric acid forms found in most competitors. Boron converts total testosterone into the free, active form the body can actually use.

A study found men taking boron daily experienced a 28% rise in free testosterone and a 39% reduction in estradiol within one week. ^[10] Reducing estradiol is especially important for men over 40, where estrogen conversion increases as testosterone declines.

Copper (0.5 mg)

Copper is included specifically to counterbalance the high zinc dose. Long-term zinc supplementation depletes copper stores, which affects red blood cell formation and immune function.

Almost no other testosterone booster accounts for this interaction. Its inclusion reflects attention to long-term safety that is rare in this category.

It is a small dose by design, providing enough to offset zinc-induced depletion without overshooting.

How Testogen Ultimate Differs From The Original Formula

Four New Ingredients Added

The updated formula adds KSM-66 Ashwagandha, Vitamin K2 MK-7, Magnesium Bisglycinate, and Copper Bisglycinate. None of these were in the original Testogen formula.

KSM-66 is arguably the most impactful addition for men over 40. Chronic stress and elevated cortisol are among the leading drivers of testosterone decline in this age group.

The original formula focused entirely on testosterone production and missed the cortisol suppression angle entirely. Vitamin K2 adds meaningful synergy with the upgraded Vitamin D3 dose.

Magnesium addresses a widespread deficiency that affects testosterone synthesis directly. Copper is a safety addition that shows the formula was designed for long-term use, not just a short-term boost.

Significantly Higher Dosages Across The Board

Almost every ingredient has been increased meaningfully. Vitamin D3 jumped from 20 mcg (800 IU) to 100 mcg (4,000 IU), a fivefold increase to reach the dose used in clinical research.

Zinc increased from 10 mg to 25 mg. Fenugreek and Korean Ginseng more than doubled.

Nettle root moved from a 4:1 to a 10:1 extract, doubling the concentration without increasing capsule size. D-Aspartic Acid was refined from 2,352 mg to 2,025 mg, keeping it firmly in the clinical range.

Premium Ingredient Forms Throughout

The original formula used standard, commodity ingredient forms. Testogen Ultimate upgrades to KSM-66, chelated minerals throughout, P5P instead of standard B6, and BioPerine instead of generic piperine.

Chelated minerals absorb meaningfully better than oxide and citrate forms. The branded extracts come with standardization guarantees and clinical data that generic forms cannot match.

Cleaner Excipients

The original formula used silicon dioxide, magnesium stearate, and standard rice flour as fillers. Testogen Ultimate uses only Nu-Flow certified organic rice concentrate as a flow agent.

The formula is fully transparent with no proprietary blends and no unnecessary excipients. Every milligram in the capsule is accounted for, active or otherwise.

Testogen Ultimate Price

Option	Supply	Price	Per Day	Best For
One-time	1 month	$69.99	~$2.33	Trying it out
Subscribe & Save (15%)	1 month	$59.49	~$1.98	Consistent use

Testogen Ultimate is sold directly through the official website with free worldwide shipping. It is not available in stores, on Amazon, or through third-party retailers.

The subscription saves 15% with no commitment and can be cancelled anytime. Three months minimum is the recommended commitment for natural testosterone support.

Check Current Testogen Ultimate Deals

Testogen Ultimate Benefits

More Energy Without Stimulants

Testosterone directly affects how energetic you feel day to day. When levels are low, fatigue becomes a constant background state rather than a response to exertion.

KSM-66 reduces the cortisol drain that saps energy through the day. B6 as P5P supports cellular energy metabolism directly.

Vitamin D3 at 4,000 IU supports the hormonal environment that keeps energy steady. The result is not a stimulant spike but a genuine improvement in baseline energy that holds without crashing.

Better Muscle Growth and Recovery

Testosterone is the primary hormone driving muscle protein synthesis. Without adequate levels, training produces less return no matter how hard you push.

D-Aspartic Acid at 2,025 mg stimulates the hormonal signaling chain that drives testosterone production at the source. Fenugreek supports free testosterone, the form that directly influences muscle response and recovery.

Zinc and Magnesium support the enzymatic processes that underpin protein synthesis. Men over 40 who feel like they are spinning their wheels in the gym often find that testosterone support is the missing variable.

Improved Mood and Mental Sharpness

Low testosterone in men over 40 is consistently linked to irritability, low motivation, and brain fog. The hormonal decline is not purely physical.

Korean Ginseng at 100 mg supports cognitive performance and mental stamina through ginsenoside activity. KSM-66 Ashwagandha reduces the cortisol-driven stress response that degrades mental clarity.

Together they address both the neurological and hormonal contributors to the mental fatigue that accumulates in men over 40.

Stronger Libido and Sexual Function

Libido is one of the first things to decline when testosterone falls. It is also one of the clearest signals that the formula is working when it returns.

Fenugreek, Korean Ginseng, Nettle Root, and Zinc each support libido and sexual health through distinct mechanisms. Fenugreek inhibits testosterone-to-estrogen conversion, while Ginseng supports neurotransmitter activity linked to sexual desire.

Nettle root increases free testosterone by freeing it from SHBG binding. Zinc supports the foundational mineral base for testosterone production.

Reduced Body Fat

Testosterone and body fat have a bidirectional relationship. Higher testosterone supports leaner body composition.

Lower levels promote fat storage, especially around the abdomen. More body fat increases aromatase activity, which converts more testosterone to estrogen and encourages further fat gain.

Boron supports free testosterone while simultaneously reducing estradiol, directly interrupting this cycle. Higher Vitamin D3 levels are independently associated with better body composition outcomes in research.

Who Is Testogen Ultimate For

Men Over 40 With Low Energy and Declining Drive

This is the core audience Testogen Ultimate is built for. After 40, testosterone drops by roughly 1% per year and the cumulative effect over a decade is significant.

If you are experiencing unexplained fatigue, reduced motivation, or a noticeable drop in libido, these are textbook symptoms of declining testosterone. Testogen Ultimate directly targets the hormonal mechanisms behind each of them.

Men Who Train But Are Not Seeing Results

Training hard with low testosterone is like pushing with the handbrake on. The effort is there but the results are not.

Testogen Ultimate supports the hormonal environment that makes training productive again. Higher free testosterone improves the anabolic response to resistance training.

Better recovery means more frequent sessions without cumulative fatigue building up. The supplement does not replace hard work, but it removes the primary biological barrier that stops hard work from paying off after 40.

Men Who Want a Transparent, Premium Formula

The fully disclosed label with no proprietary blends means you can verify every dose before you buy. This is increasingly rare in the supplement industry.

Every ingredient form is specified and every dose is published. There are no hidden fillers and no label dressing.

Who It Is Not For

Testogen Ultimate is not a substitute for medically prescribed testosterone replacement therapy. Men with clinically diagnosed hypogonadism should work with a doctor.

It is not suitable for women or men under 18. Men taking blood thinners should consult a doctor before starting due to the Vitamin K2 content.

Men on medication for hormonal conditions or with pre-existing health conditions should seek medical advice before starting.

My Experience Taking Testogen Ultimate

I have been using Testogen Ultimate for twelve weeks as part of my regular training and recovery routine. At 42, I am exactly the target demographic for this product.

I started at four capsules each morning with breakfast. The first week was unremarkable, which I expected.

Natural supplements working through hormonal pathways take time to accumulate. There were no side effects and no digestive issues, even with the 25 mg zinc dose.

By week two, the most noticeable change was a steadier baseline of energy. I was getting through long training days without the usual afternoon dip that had become my normal.

The change was subtle enough that I only noticed it clearly when I missed a few days and felt the difference.

By week four, my workouts had improved measurably. I was recovering faster between sessions and sustaining performance across a full week of training.

I pushed heavier weights and hit higher volumes without feeling wrecked the following morning.

The mood shift was harder to pin down but real. I felt less reactive to daily stressors and more focused at work.

I was more motivated to train rather than looking for reasons to take a rest day. My wife commented on it before I had consciously acknowledged it myself.

Libido improved noticeably around the six-week mark. For me this was the clearest hormonal signal that something meaningful was shifting.

The KSM-66 Ashwagandha appears to be contributing significantly on the stress and cortisol side. The reduction in background mental tension was something I did not expect to be as noticeable as it was.

I sleep better and feel less wired but tired at the end of the day. Recovery feels more complete than it did before starting.

By week twelve, the cumulative effect is a leaner body composition, better gym performance, and a general sense of operating more like I did five years ago. Results for other men will vary, but my experience with this formula has been consistently positive.

Customer Testogen Ultimate Reviews and Testimonials

Across Trustpilot and the official website, the most consistent feedback pattern involves energy and mood improvements in the first month, followed by more noticeable physical changes from month two onward. This timeline aligns with how natural testosterone support actually functions.

Men in their 40s and 50s are the most vocal demographic in the reviews. Common themes include feeling more like themselves again, improved gym performance after months of stagnation, and a renewed sex drive.

Several reviewers specifically mention that they only realized how much their testosterone had dropped when they saw how they felt on the supplement.

The sleep improvement angle comes up frequently and is likely connected to the KSM-66 cortisol reduction effect. A number of reviewers who did not mention stress as a concern still noted deeper, more consistent sleep after a few weeks.

This is a downstream benefit that the original Testogen did not produce as consistently.

Critical reviews focus on two main areas: price and timeline expectations. Some users feel the cost is high for a natural supplement.

Others expect visible muscle gains within the first two to three weeks. Natural testosterone support does not operate on that timeline and requires at least three months for the full cumulative effect.

The overall Trustpilot rating sits at 4.4 stars from several thousand verified reviews. This is a strong score in a category where many products underdeliver on their marketing claims.

Testogen Ultimate Side Effects

Testogen Ultimate uses natural ingredients and is generally well-tolerated. Serious side effects are not reported and the formula contains no stimulants, synthetic hormones, or banned substances.

The most commonly reported mild side effect is digestive discomfort during the first week. This is typically attributed to fenugreek or the 25 mg zinc dose.

Taking the capsules with a meal rather than on an empty stomach resolves this in most cases within the first five to seven days.

The inclusion of copper at 0.5 mg directly addresses the copper depletion risk from long-term zinc supplementation. Without the copper counterbalance, high zinc intake over months can suppress copper levels, leading to fatigue and weakened immunity.

The fact that this is included proactively is a genuine safety advantage over most formulas in this category.

Men on blood thinners should consult a doctor before starting due to the Vitamin K2 content. K2 has a direct role in coagulation pathways and its interaction with blood-thinning medication needs medical management.

Men with existing hormonal conditions, prostate issues, or on testosterone replacement therapy should also seek medical advice before starting.

Testogen Ultimate Alternatives

TestoPrime

TestoPrime uses 12 ingredients including KSM-66 Ashwagandha and D-Aspartic Acid, with a similar approach to natural testosterone support. The formula targets testosterone through a comparable multi-angle strategy to Testogen Ultimate.

The key differences come down to dosing specifics. TestoPrime uses 2,000 mg of D-Aspartic Acid vs Testogen Ultimate's 2,025 mg, so the two are effectively matched on that ingredient.

Where Testogen Ultimate pulls ahead is in the higher Vitamin D3 dose (4,000 IU vs 2,000 IU), the addition of Magnesium and Vitamin K2, and the copper inclusion for long-term zinc safety.

TestoPrime does have one significant advantage: a lifetime money-back guarantee, one of the strongest in the supplement industry. It is also slightly more competitively priced on a per-bottle basis.

For men uncertain about committing financially to a new supplement, the lifetime guarantee reduces the risk substantially. For men who want the most clinically dosed and comprehensively formulated option, Testogen Ultimate has the stronger case.

Read my TestoPrime review for my experience taking this supplement.

TestoFuel

TestoFuel focuses specifically on the muscle-building application of testosterone support. Its standout ingredient is oyster extract, a whole-food zinc source that delivers zinc alongside co-factors and trace minerals in their natural food matrix.

It also uses a higher D-Aspartic Acid dose of 2,300 mg and includes Vitamin D3, Ginseng, Fenugreek, and Vitamin K2.

Where TestoFuel differs from Testogen Ultimate is in its narrower scope. It does not include KSM-66 Ashwagandha or Magnesium, so the cortisol suppression and broader hormonal support angles are less developed.

This makes TestoFuel a better fit for men whose primary goal is gym performance specifically. For men over 40 dealing with the full spectrum of low testosterone symptoms including stress, mood, and energy, Testogen Ultimate addresses more ground.

TestoFuel is priced similarly to Testogen Ultimate and is only available through the official website. It has a strong track record in the bodybuilding community.

Read my TestoFuel review for my experience taking this supplement.

Prime Male

Prime Male is the most directly comparable product to Testogen Ultimate in terms of target audience. It is specifically positioned for men over 40, with ingredients chosen for the hormonal environment of older men.

Its standout addition is luteolin, a bioflavonoid that blocks the aromatase enzyme responsible for converting testosterone into estrogen. Aromatase activity increases with age and body fat, making this an increasingly significant issue for men in their 40s and 50s.

Prime Male also includes Ashwagandha, D-Aspartic Acid, Vitamin D3, Zinc, Magnesium, Vitamin K2, Boron, and BioPerine, giving it significant overlap with Testogen Ultimate's formula. The main differentiator is the luteolin and its emphasis on estrogen management alongside testosterone production.

Where Testogen Ultimate edges ahead is in the quality of the branded extracts (KSM-66 specifically) and the copper inclusion for zinc safety. Prime Male uses ashwagandha but not the KSM-66 form, which has a more robust clinical evidence base.

For men whose primary concern is estrogen conversion, Prime Male's luteolin content makes it worth considering. For men who want the most evidence-backed ingredient forms, Testogen Ultimate has the stronger case.

Read my Prime Male review for my experience taking this supplement.

Frequently Asked Testogen Ultimate Questions

Does Testogen Ultimate Actually Work?

Testogen Ultimate contains ingredients at doses shown to support testosterone in peer-reviewed clinical research. Natural testosterone boosters do not replicate TRT results, but the ingredients in this formula have real clinical evidence behind them.

Most men report meaningful improvements in energy, mood, and libido within four to six weeks of consistent use. The cumulative benefit builds over time rather than peaking and plateauing quickly.

How Long Does It Take To See Results With Testogen Ultimate?

The first changes most men notice are energy and mood improvements, typically within two to three weeks. These come primarily from the KSM-66 cortisol reduction, Vitamin D3, and B6 P5P components.

Physical changes typically take eight to twelve weeks of consistent daily use to become clearly visible. Libido improvements tend to appear around the four to six week mark.

For the full hormonal benefit, a minimum three-month commitment is recommended.

How Do I Take Testogen Ultimate?

The recommended dose is four capsules taken each morning with breakfast. Taking them with food improves absorption of the fat-soluble vitamins and reduces the chance of digestive discomfort.

Consistency is critical with natural testosterone support. Missing days regularly will undermine the cumulative hormonal effect the formula is designed to build over time.

Is Testogen Ultimate Safe?

Testogen Ultimate uses natural ingredients with no banned substances, synthetic hormones, or harsh stimulants. It is generally safe for healthy adult men over 18.

The inclusion of copper at 0.5 mg specifically protects against the zinc-induced copper depletion that most formulas at this zinc dose ignore.

Men on blood thinners should consult a doctor before starting due to the Vitamin K2 content. Men with pre-existing hormonal conditions or on prescribed medication should also seek medical advice first.

Can I Stack Testogen Ultimate With Other Supplements?

Testogen Ultimate stacks well with protein powders, creatine, and standard training supplements. Be cautious stacking with other zinc-containing products, as Testogen Ultimate already provides 25 mg per serving.

Avoid stacking with other vitamin K supplements or hormonal products without medical guidance.

Where Can I Buy Testogen Ultimate?

Testogen Ultimate is only available directly from the official Testogen website. It is not sold in stores, on Amazon, or through any third-party retailers.

Purchasing through unofficial channels risks receiving counterfeit product or old pre-reformulation stock. Buying direct also gives access to the subscription discount structure.

What Is The Difference Between The Old Testogen And Testogen Ultimate?

The new formula adds four entirely new ingredients (KSM-66 Ashwagandha, Vitamin K2 MK-7, Magnesium Bisglycinate, and Copper Bisglycinate), significantly increases dosages across the board, and upgrades every ingredient to a premium form. Vitamin D3 increased from 800 IU to 4,000 IU and zinc from 10 mg to 25 mg.

It is a thorough reformulation, not a minor update. The original Testogen was a solid product. Testogen Ultimate is a meaningfully different formula.

Summary

Testogen Ultimate is a meaningful step forward from the original formula. With 13 clinically dosed ingredients, premium forms throughout, and a fully transparent label, it addresses testosterone decline in men over 40 more comprehensively than most natural boosters on the market.

The addition of KSM-66 Ashwagandha is the standout change. Chronic stress and elevated cortisol are among the most significant drivers of testosterone decline after 40.

The original formula missed this entirely. Testogen Ultimate addresses it with the most clinically validated form of ashwagandha available.

The Vitamin D3 upgrade to 4,000 IU, chelated minerals throughout, and MK-7 Vitamin K2 confirm this is not a cosmetic reformulation. Every upgrade has a clinical rationale behind it.

For healthy men over 40 who want to support their natural testosterone levels, improve energy and mood, and get more from their training, Testogen Ultimate is one of the best natural options available.

References

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2. Roshanzamir, F., & Safavi, S. M. (2017). The putative effects of D-Aspartic acid on blood testosterone levels: A systematic review. International Journal of Reproductive Biomedicine, 15(1), 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5340133/

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7. Pilz, S., Frisch, S., Koertke, H., Kuhn, J., Dreier, J., Obermayer-Pietsch, B., & Zittermann, A. (2011). Effect of vitamin D supplementation on testosterone levels in men. Hormone and Metabolic Research, 43(3), 223-225. https://pubmed.ncbi.nlm.nih.gov/21154195/

8. Prasad, A. S., Mantzoros, C. S., Beck, F. W., Hess, J. W., & Brewer, G. J. (1996). Zinc status and serum testosterone levels of healthy adults. Nutrition, 12(5), 344-348. https://pubmed.ncbi.nlm.nih.gov/8875519/

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10. Naghii, M. R., Mofid, M., Asgari, A. R., Hedayati, M., & Daneshpour, M. S. (2011). Comparative effects of daily and weekly boron supplementation on plasma steroid hormones and proinflammatory cytokines. Journal of Trace Elements in Medicine and Biology, 25(1), 54-58. https://pubmed.ncbi.nlm.nih.gov/21129941/