There are certain supplements that repetitively present as being required by almost all clients and for that reason we have decided to put them into a series of posts explaining how and why they are beneficial.
This Essential Supplements post is on Zinc.
Out of all the supplements/vitamins/minerals that are available, no other has such a strong correlation with male reproduction and healthy testosterone levels as zinc. To put it bluntly, low zinc levels = low testosterone levels. Furthermore the benefits of zinc extent beyond the scope of testosterone into areas such as immunity, male fertility, cell regeneration, healthy fetus growth to name a few and that is the reason why it tops our list of essential supplements. It must be stated that this is one of the easiest subjects to write about because there are so many studies showing these correlations.
Zinc’s role in the body:
Zinc is involved in numerous aspects of cellular metabolism, it plays a role in immune function, protein synthesis, wound healing, DNA synthesis and cell division. Zinc also supports normal growth and development during pregnancy, childhood, and adolescence (Ods.od.nih.gov 2014).
Zinc is required to be consumed on a daily basis to maintain a steady state, as the body has no ability to store zinc (Rink, 2000). Furthermore intense exercise has been shown to place further demands on the body’s existing zinc levels (Brun et al., 1995). Thus under this premise it is easy to see how an individual’s zinc levels can easily become depleted.
How zinc specifically relates to our lives:
Male Fertility: Low zinc levels are associated with decreased sperm concentration and count from which a study found that the “dietary restriction of zinc can affect testicular function adversely“(Abbasi, Prasad, Rabbani and DuMouchelle, 1980). In a study of males that had idiopathic (unexplained) infertility that had persisted for more then 5 year, 24% of the males were able to achieve pregnancy with their wife after receiving zinc supplementation for less then 3 months (Netter, Nahoul and Hartoma, 1981).
Testosterone production: Zinc levels are positively correlated with healthy adult testosterone levels (Prasad et al., 1996). There may be an increasing demand with age as one study found the correlation to be “statistically significant” with males aged between 36-60 years of age (Hartoma, 1977). Furthermore these effects can be witnessed even after zinc levels have been deficient for a relatively short period of time (Hunt, Johnson, Herbel and Mullen, 1992).
IGF-1 levels in children: Studies focusing on children show that zinc deficiency relates to growth and cell regeneration though effects on insulin-like growth factor 1 (IGF-1). Therefore zinc is particularly important for children, due to their obvious growth requirements (Prasad and S, 1998). Thus zinc deficiency has serious implications for prepubertal children due to the degree of growth that they require and because of these effects on IGF-1 (Imamoglu et al., 2005). Though at time of writing no studies could be produced, one would assume that zinc has some bearing on adequate levels of IGF-1 in the trained adult, which would be of particular interest to individuals seeking optimum muscle growth.
Retarded growth and sexual maturation in children: Low zinc deficiency has been associated with retarded growth and sexual maturation in children in a manner that mimics idiopathic hypopituitarism (Sandstead et al., 1967). This correlation will be due in part to the effect that a zinc deficiency exerts on sex hormones, as mentioned above.
Increased pregnancy complications: “A mild deficiency of zinc in pregnancy is associated with increased maternal morbidity, abnormal taste sensation, prolonged gestation, inefficient labor, atonic bleeding, and increased risks to the fetus” (Prasad and S, 1996). The complications with growth and sexual maturation stated in the previous point also apply to the fetus when it is faced with zinc deficiency (Favier, 1992).
Immunity: Zinc deficiency has been shown to be a major factor in humans with deficient immune systems (Keen and Gershwin, 1990). In such a situation zinc deficiency results in an individual having an increased susceptibility to pathogens (Shankar, Prasad and S, 1998). Quite literally immune cells will show decreased function when faced with zinc depletion (Keen and Gershwin, 1990).
Take home message: Zinc deficiency can have seriously detrimental effects on your ability to recover from exercise, gain muscle and stay lean. Whilst these factors are a concern for an exercising individual, the greater implications are more profound with fertility issues, immune problems, complications during pregnancy and fetal development problems. Thus is goes without saying that zinc supplementation is very important and should be treated accordingly.
How can I test my zinc levels?:
Naturopaths do it via a simple zinc tester. This is a liquid form of zinc (liquid zinc sulphate), where you hold the liquid in your mouth to evaluate your zinc levels. You then get graded on how strong the taste sensation is, e.g. no taste means your zinc levels are very low. With resulting supplementation a retest in a few of weeks will result in a very different taste. When the liquid instantly tastes horrible, then you know your zinc levels have been restored. Spoke to your local vitamins store and they will be able to provide you with the liquid zinc and guide you through the process. NOTE: Almost every client we test, has a very poor initial test result. Low zinc levels are very common and this is why we tend to harp on about the issue.
Not all forms of zinc are created equal:
Some forms of zinc like zinc sulphate, when taken on an empty stomach can result in very strong nausea. Like other vitamins some forms are more absorbable and have affinities for certain tissues. Our recommendation for zinc always goes to the Poliquin brand, benefit is that it isn’t expensive. But you should be able to find other options by speaking to your local vitamin store and asking for highly absorbable forms of zinc.
Warning: Some zinc formulas also include vitamin A, if you are taking large doses of these combined zinc formulas, please make sure that you pay attention to how much vitamin A that you are consuming, as it can be toxic in large amounts.
When to take your zinc:
Spread your zinc out over the day and understand that restoring zinc levels doesn’t happen over a couple of days it can take months and will require maintenance thereafter. At Eastside Fitness we have specific protocols for restoring zinc levels but unfortunately that is not something that we will just post here without first seeing and evaluating the individual.
All the best in health,
Abbasi, A., Prasad, A., Rabbani, P. and DuMouchelle, E., 1980. Experimental zinc deficiency in man. Effect on testicular function. The Journal of laboratory and clinical medicine, 96(3), pp.544–550.
Brun, J., Dieu-Cambrezy, C., Charpiat, A., Fons, C., Fedou, C., Micallef, J., Fussellier, M., Bardet, L. and Orsetti, A., 1995. Serum zinc in highly trained adolescent gymnasts. Biological trace element research, 47(1-3), pp.273–278.
Favier, A., 1992. The role of zinc in reproduction. Biological trace element research, 32(1-3), pp.363–382.
Hunt, C., Johnson, P., Herbel, J. and Mullen, L., 1992. Effects of dietary zinc depletion on seminal volume and zinc loss, serum testosterone concentrations, and sperm morphology in young men. The American journal of clinical nutrition, 56(1), pp.148–157.
Imamoglu, S., Bereket, A., Turan, S., Taga, Y. and Haklar, G., 2005. Effect of zinc supplementation on growth hormone secretion, IGF-I, IGFBP-3, somatomedin generation, alkaline phosphatase, osteocalcin and growth in prepubertal children with idiopathic short stature. Journal of Pediatric Endocrinology and Metabolism, 18(1), pp.69–74.
Keen, C. and Gershwin, M., 1990. Zinc deficiency and immune function. Annual review of nutrition, 10(1), pp.415–431.
Netter, A., Nahoul, K. and Hartoma, R., 1981. Effect of zinc administration on plasma testosterone, dihydrotestosterone, and sperm count. Systems Biology in Reproductive Medicine, 7(1), pp.69–73.
Ods.od.nih.gov, 2014. Zinc — Health Professional Fact Sheet. [online] Available at: <http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/> [Accessed 26 Apr. 2014].
Prasad, A., Mantzoros, C., Beck, F., Hess, J. and Brewer, G., 1996. Zinc status and serum testosterone levels of healthy adults. Nutrition, 12(5), pp.344–348.
Prasad, A. and S, a., 1996. Zinc deficiency in women, infants and children. Journal of the American College of Nutrition, 15(2), pp.113–120.
Prasad, A. and S, a., 1998. Zinc in human health: an update. The Journal of Trace Elements in Experimental Medicine, 11(2-3), pp.63–87.
Rink, L., 2000. Zinc and the immune system. Proceedings of the Nutrition Society, 59(04), pp.541–552.
Sandstead, H., Prasad, A., Schulert, A., Farid, Z., Miale, A., Bassilly, S. and Darby, W., 1967. Human zinc deficiency, endocrine manifestations and response to treatment. The American journal of clinical nutrition, 20(5), pp.422–442.
Shankar, A., Prasad, A. and S, a., 1998. Zinc and immune function: the biological basis of altered resistance to infection. The American journal of clinical nutrition, 68(2), pp.447–463.