Have you heard about the claims that zinc can increase testosterone levels?
There are plenty of attention grabbing headlines around this humble trace mineral that report a correlative effect in low testosterone levels; if you are deficient in zinc then your hormone levels will be affected.
In this piece, we take a look at the role of zinc in our overall health, whether it can have an impact on our testosterone levels and how you can supplement zinc in your diet.
What is Zinc and Why is it Important?
An important trace mineral, zinc is used by the body for cell division, the immune system and breaking down carbohydrates. Zinc boosts the efficacy of insulin and plays a critical role during childhood for healthy growth and development. Zinc is also a major part of how we smell and taste foods.
Healthy adults naturally have around 2-3g of zinc in the body at any given time which is distributed throughout the organs, fluids, cells, brain and tissue.
Second only to iron in terms of concentration in the human body, zinc can be found in animal proteins. Whilst zinc is found in vegetable protein it is not as readily available for use and is usually excreted before being broken down. As a result, people who stick to a vegetarian diet and/or a low protein diet can find that they have a zinc deficiency.
Symptoms of a diet that is deficient in zinc include:
- Wounds taking a long time to heal
- Slow growth
- Hair loss
- Lack of appetite
- Frequent infections
- Problems with sense of taste and/or smell
- Hypogonadism in men
As well as vegetarians, athletes are often found to have a zinc deficiency as this trace mineral is excreted in great quantities through sweating.
What is Hypogonadism?
A lack of zinc in your diet can cause hypogonadism in men which effectively means that the body ceases (or limits) production of hormones, including testosterone.
Symptoms of hypogonadism in men include muscle loss, decreased libido and enlargement of the breast tissue. If left untreated, it can cause impotence, infertility, weakness and osteoporosis.
So, does Zinc Increase Testosterone?
The simple answer is yes, zinc does increase testosterone levels; however, it doesn’t increase testosterone levels beyond the range of what is normal for you. Effectively, if you are suffering from a zinc deficiency, adding zinc back into your diet can improve your testosterone levels to typical levels.
There are several clinical studies that show strong supporting evidence to the claims that zinc can boost testosterone levels in men suffering from a deficiency of this trace mineral.
A 1981 study, entitled “Effect Of Zinc Administration On Plasma Testosterone, Dihydrotestosterone, And Sperm Count” conducted over a period of six months on 37 infertile men showed that a supplement of zinc:
- Increased circulating levels of DHT (dihydrotestosterone).
- Increased sperm count.
- Improved fertility.
- Boosted testosterone levels.
A study undertaken in 2010 (“Impact of oral zinc therapy on the level of sex hormones in male patients on hemodialysis”) using male patients as test subject who were undertaking hemodialysis for chronic renal failure showed that a daily 250mg supplement of zinc sulfate:
- Increased testosterone levels.
- Increased LH levels.
- Did not affect prolactin or FHS levels.
A further study in 2007 entitled “Effect Of Fatiguing Bicycle Exercise On Thyroid Hormone And Testosterone Levels In Sedentary Males Supplemented With Oral Zinc” found that exercise in sedentary men depleted the level of testosterone and thyroid hormones. However, zinc was found to prevent his depletion and showed an improvement in both resting and fatigue hormone levels.
This was found to be similar to the 2006 study (“The effect of exhaustion exercise on thyroid hormones and testosterone levels of elite athletes receiving oral zinc”) in which two groups of elite athletes were also tested to exhaustion; one group were given a supplement of 3mg/kg daily supplement of zinc sulfate and one group was given a placebo. The placebo group found that their resting and fatigue hormone levels were reduced whereas the group using zinc supplements were able to preserve their testosterone and thyroid hormone levels.
What are the Best Sources of Zinc?
Zinc can be found in plenty of dietary sources or can be taken as a supplement; either as a single dose or as a combination in something like ZMA.
Dietary sources of zinc include:
- Whole grains.
- Crab and lobster
- Red meat as well as chicken and fish.
What is ZMA?
ZMA is a supplement that contains a mixture of Zinc Monomethionine Aspartate, Magnesium Aspartate and Vitamin B6. It is often used by athletes and sportsmen to aid recovery after workout as it helps support deep sleep thus aiding muscle repair and growth. A common, and welcome side effect, is the fact that the zinc can restore a deficiency and thus improve testosterone levels. In men who have suffered from a deficiency of this trace mineral, there is a clear benefit of improved strength as well as diminishment of breast tissue growth.
You can read our full review of ZMA here when we compare it to the natural plant extract supplement, tribulus terrestris (also marketed at boosting testosterone levels).
Featured image via Flickr.