T Nation

Why Does Zinc Lower My Sex Drive?


I've noticed lately that my libido drops when I take zinc. As we all know, zinc is essential in many enzyme reactions that contribute to the production of testosterone. Zinc deficiency is known to cause low testosterone, and low libido. I am not currently taking a multi.

When I was in my twenties, I used zinc for libido with great results. Now I'm forty, and when I take zinc at 50 mg per day, I notice my libido drops to shit after a few days of taking it. 2 to 3 days after I cease the zinc supplementation, my libido returns to normal.

Could it be that the zinc I'm using is the cheap, shitty zinc from the grocery store? Could it be that my zinc intake is already high, and an overdose is causing a paradoxical effect, or the fact that the incorrect ratio of copper and zinc in my system is off and causing a paradoxical effect?


The first thing I thought of was copper. Zinc and copper are both present in some enzymes, but increasing either zinc or copper I believe inhibits absorption of the other, so sometimes adding one can reduce the overall amount of the enzymes produced. Usually its the other way around though, that adding copper paradoxically blocks copper containing enzymes because they also contain zinc.

It looks like high zinc intake can block copper too, but I have read about doses of over 100 mg a day for several months.

Personally I don’t think this is the reason. I think that it may be something like a beta blocking effect as Zinc supplements can sometimes be relaxants. I’ll research more.


Zinc in higher amounts can increase testosterone partially by stopping the conversion of testosterone to dihydrotestosterone (DHT). DHT does everything testosterone does 3.5 times better than testosterone EXCEPT build muscle. So DHT will lead to masculine features, aggression, harder physique, body/facial hair and LIBIDO 3.5 times more than testosterone. It just won’t build muscle like testosterone. So if you are stopping the conversion of DHT this would account for a slightly lower libido. What you can do is take zinc every other day or on weekends, or on any cycle you decide works for you.


Great info bszpyrka

Wasn’t DHT supposed to be one of the substances that Barry Bonds took in the “clear”? I have read that it may make you feel like you are getting an anabolic effect, but that it does not promote anabolism. Is there a current clinical use for DHT?


I have found some studies that excess Zinc causes oxidative stress on arteries. High oxidative stress can reduce Testosterone in the long term.

I was also thinking that Zinc is a mild relaxant. Adrenergic agents (stimulants) can cause acute boost in T but chronic depletion. Caffeine and Nicotine for example both cause acute T and libido BOOST, so I considered that if zinc is a relaxant it might be moderating adrenaline.

Zinc also can raise BP at both low AND high levels.

Anyway, when considering libido, I would not be thinking of copper/zinc enzyme issues first. I would be thinking of a) direct effect on sex hormones then b) adrenergic modulation effects and c) psychotropic effects (depression).

Since we have a sex horomone explanation, that would be the logical choice.


So if Zinc blocks DHT does it have an effect on male pattern baldness or on BPH?


Your ability to respond/absorb may have changed. Yes, quality of product could be shit and causing a problem. But it would probably just be worth it to get your zinc levels checked, then you don’t have to guess. If you are high, and creating more T through a variety of conversions you could be also producing more E. Push estrogen too high or too low and you can tank libido. Other than that there could be some kidney issues and some other stuff so its probably best to run blood panels or cycle the zinc even.


It is also often said that Zinc can be a aromatase inhibitor. Since libido in adult heterosexual men is highly dependent on estrogen levels in the brain’s “libido circuits”, a decline in estrogen due to aromatase inhibition from zinc could potentially lead to a decrease in libido. Althought the effects seem to be pretty dramatic in your case.


Maybe change up the type of zinc just to make sure it is you and not the product. Different zinc types have different absorbability than others as well as different amounts of actual elemental zinc. I tried zinc gluconate at 50mg and didn’t notice any difference. Chelated definitely worked (50mg was way too much of that stuff) but I think zinc monomethionine with a little bit of copper in it proved the best to me. Picolinate also works well.


By the way, one of the reasons I eat beef liver 1-2 times a week is the copper. Its also a reason NOT to consume it more than about 2x per week (as it contains 10-15x the daily minimum and blocks zinc absorption as well as possibly inhibiting some enzymes at high levels). Also limit liver as 4 oz has about 350% of daily retinol. 8-12 OZ a week is optimal.