Vitamin C and Testosterone: The Protective Antioxidant

By Ali Kuoppala | Last reviewed Tue 25 September 2018

Medical Review by Dr. Vlad Belghiru, MD

Vitamin C (ascorbic acid) is likely the most researched, well known, and most-used nutritional supplement in the whole World. Not only that, but it’s also safe, cheap, and available pretty much all around the globe.

But what about the effects of vitamin C on male testosterone levels? That’s a topic not so often talked about.

At least until now:

Ascorbic Acid and Testosterone Levels

vitamin c testosteroneVitamin C is an essential vitamin for human survival, and as I said above, one of the cheapest, safest, and most widely used nutritional supplements in the World.

It’s water-soluble, and its main function in the body is to serve as an antioxidant (much like vitamin E, it’s fat-soluble brother)

However, what most people don’t know, is that vitamin C can also be a pro-oxidant. How it acts depends on what the body needs at any given time.

Ascorbic acid is also needed in the biosynthesis of multiple bodily enzymesAnd when used in combination with garlic, vitamin C is ridiculously effective at increasing nitric oxide levels, and therefore also blood flow.

But how does the World’s most used vitamin affect male testosterone levels? That’s what we’re about to find out:

a) First, of, there’s an in-vitro (test tube) study where it was found that vitamin C as an electron donor, can regenerate damaged testosterone molecules by up to 58%. In a similar in-vitro study, vitamin C was able to increase testosterone levels in testicular Leydig cells due to enzyme upregulation.

b) Several animal studies have shown that vitamin C protects the testicular Leydig cells from oxidative stressors, and thus, preserves testosterone levels from; alcohol, noise-stress, lead, burns, cadmium, antibiotics, arsenic, PCBs, aluminum, aflatoxin, and endosulfan. Similar protective effects have been seen in humans too.

c) So, ascorbic acid clearly preserves testosterone molecules from oxidative damage, but could it increase testosterone levels in healthy gonads? This rodent study suggests so, and in this human study, vitamin C significantly increased sperm quality, motility, and volume. However, the only two human studies that I’m aware of which examined vitamin C’s direct effects on testosterone levels, showed no significant increases in T after ascorbic acid supplementation (study, study).

d) The last thing worth mentioning here is the fact that vitamin C supplementation is known for its cortisol (stress hormone) lowering effects. This, in turn, should improve the testosterone to cortisol ratio more in favor of testosterone, creating a more anabolic environment in the body (study, study, study, study).

So who could benefit from vitamin C supplementation?

Answer: Well, for starters pretty much anyone who wants to protect their gonads from oxidative damage. If you’re exposed to any of the things in point “b)” above, then increased ascorbic acid intake (and for that matter other antioxidants too) would be advisable, just to preserve testosterone molecules from cellular damage.

Another group that could benefit from extra vitamin C intake would be people who train hard, as ascorbic acid helps in suppressing the exercise-induced rise in cortisol, and therefore would improve the testosterone to cortisol ratio in favor of anabolism.

However, if you don’t train hard, and if you suspect that your diet and overall health is in such a good order that there’s no oxidative damage going on in the testicles, then vitamin C supplementation is probably not going to do much for your hormones.

How much ascorbic acid should you take?

Answer: In a healthy scenario, the human body has a pool of vitamin C of about 2 grams. This can be maintained with ~100 mg’s of daily ascorbic acid supplementation, hence why the RDA of vitamin C is 100-200 mgs. This low amount can be easily attained through the diet (citrus fruits, kiwi, etc), or from a high-quality multi-vitamin.

However, if you’re under stress, and/or exposed to compounds that cause oxidative stress in the body, a higher dose (1-5 grams) of vitamin C could be taken to protect the Leydig cells from damage.

To lower the exercise-induced rise in cortisol, 1-3 grams of ascorbic acid should be enough.

What’s the best form of vitamin C to supplement with?

Answer: The most basic and cheap ascorbic acid supplements are pretty good. However, I tend to recommend this berry extract (affiliate link), simply due to the fact that it’s from a whole-food source.

Also, if your goal is only to maintain the body’s natural pool of vitamin C, you should be covered just by eating some citrus fruits on a daily basis, or by taking a multi-vitamin that includes at least 100 mg’s of ascorbic acid.


Does vitamin C increase testosterone levels? Not directly if you believe the latest human studies, and this is likely due to the fact that in a healthy scenario, the human body maintains a pool of available vitamin C in various tissues (testicles, pituitary gland, thyroid, liver, etc).

However, supplemental ascorbic acid does protect testosterone molecules exceptionally well from oxidative damage during the times of stress. Probably because the bodily pool is drained faster when exposed to various stressors.

And that’s also why I believe most men could benefit from extra vitamin C supplementation. Because of the modern day diet of processed foods, environmental toxins, obesity, and sedentary lifestyles, most men do have some oxidative stress going on inside their gonads.

Ali Kuoppala

Ali Kuoppala is the founder of Anabolic Men. He has authored and co-authored multiple men's health books and focuses on uncovering the methods of optimizing hormonal health. To date, his articles on various websites have been read more than 15-million times. To read more about Ali, visit his Medium article.