Top Ten Benefits of Zinc
By Charles Poliquin 2/9/2012 1:05:04 PM
Improve all aspects of your health and well-being by making sure you get enough zinc in your diet. Many people know about zinc for its immune boosting properties, but this mineral is actually a wonder of health benefits. Researchers write that “zinc is such a critical element in human health that even a small deficiency is a disaster.”
Zinc is so important because it is found in every tissue in the body and is directly involved in cell division. It is a powerful antioxidant, helping to prevent cancer, but zinc also is directly involved in proper endocrine function and the maintenance of ideal hormone levels.
Zinc deficiency makes both men and women infertile and causes low libido.
Additionally, adequate zinc is necessary for optimal physical performance, energy levels, and body composition. Zinc affects protein synthesis and is required for proper function of red and white blood cells. It is highly concentrated in our bones, the pancreas, kidneys, liver, and retina.
Low zinc also exacerbates the effects of stress on the body and accelerates aging.
This article will give you the top ten reasons why you should attend to your zinc levels and ensure your loved ones are doing so as well. Be aware that zinc deficiency is not only prevalent in malnourished individuals or developing countries. Rather, it is widespread in the U.S. and the UK, and it is particularly common in areas where the population eats a large amount of cereal and grain proteins. Low zinc is common in men, women, and children, and I’ve found that over 90 percent of my clients and athletes are zinc deficient.
Groups At Greatest Risk of Low Zinc
Zinc deficiency occurs from not eating enough zinc-rich foods. Zinc is found in large concentrations in meat, some seafood—
oysters contain the largest concentration of all known foods—
and dairy. Whole grains and legumes contain zinc, but it is bound to phytates in these plant-based foods, making the zinc inaccessible by the body. Vegetarians are at greatest risk of zinc deficiency, but alcoholics and people with digestive issues and poor stomach acid are also highly susceptible. Taking medications may produce zinc deficiency and low levels of almost all essential nutrients. Women on the birth control pill or on hormone replacement therapy are at greater risk of deficiency.
Symptoms of Zinc Deficiency
Low zinc will produce an altered sense of taste leading to cravings of saltier, sweeter food. Deficiency can also be indicated by diarrhea, low energy, chronic fatigue, infertility, poor immunity, bad memory, inability to focus, ADD symptoms, slow wound healing, nerve dysfunction, and ringing in the ears.
Take note that symptoms may be present, but because they are so diverse and associated with other health conditions, it’s often hard to make the link to zinc deficiency without a test. A guide is provided at the end of this article on how to test your zinc level.
#1 Improve Athletic Performance and Strength
Adequate zinc directly affects athletic performance and strength development from training because it plays a primary role in anabolic hormone production. Research shows having ample zinc available in the body allows for a more robust release of the three most important anabolic hormones, testosterone, growth hormone and insulin-like growth factor-1 (IGF-1). Without these, you’ll miss out on muscle and strength development from your hard work in the gym.
A recent study in the journal Biological Trace Element Research highlights the boost that raising zinc levels can give to testosterone production following exercise. Researchers found that giving trained athletes a zinc supplement for four weeks prior to an exhaustive exercise test resulted in a greater post-workout testosterone response than a placebo.
Taking zinc produced higher testosterone levels in the athletes than taking a selenium supplement (a powerful antioxidant that minimizes oxidative stress in the testis). Researchers note that zinc enhances the conversion rate of androstenedione to testosterone, and that paired with high-intensity exercise, it allows the body to produce testosterone at an even higher rate.
Male and female athletes will benefit from adequate zinc since this mineral ensures healthy release of growth hormone and IGF-1, which are essential for performance and muscle development in both sexes. Plus, the boost to testosterone post-workout can improve strength gains recovery in men. And, as you’ll see below, having enough zinc will give you more energy and improve metabolism.
#2 Support Male Reproductive Health and Fertility
Zinc is a critical mineral for robust testosterone levels, and the cells of the male prostate require a very high concentration of zinc to work optimally. Low zinc in men impairs testosterone production, puts them at risk for developing prostate cancer, and causes infertility. Inadequate zinc has also been linked to low libido.
One recent study of 88 men aged 40 to 60 years showed that those with normal testosterone levels had significantly higher zinc compared to those with low testosterone levels. Low zinc was directly correlated with low testosterone levels, which put the men at greater risk of symptoms of male menopause.
Just as important, zinc is used to produce enzymes that initiate cell division,
but the male prostate tissue requires ten times more zinc than other cells in the body to stay healthy. Adequate zinc level in the prostate protects the cells from damage, inflammation, and cancer development. Also, once the prostate cells are damaged and become cancerous, they lack the ability to accumulate zinc, leading to greater propagation of cancer cells that produce to tumors.
Giving a large dose of therapeutic zinc to rats with prostate cancer halted cancer cell proliferation and helped the rats maintain body weight, which is an indicator of better overall health and homeostasis. There was reduced evidence of biomarkers that indicate oxidative stress and inflammation in the prostate from the zinc supplement. Overall enzyme levels were better.
In contrast, a placebo group had a rapid increase in cancer cell growth and decrease in body weight. There was also a 50 percent increase in DNA damage and inflammation during the study period, indicating a progressively diseased prostate cancer state.
Researchers write that zinc is a “promising anti-cancer treatment” and that regular supplementation when men are healthy with no evidence of cancer is the best prevention. They also suggest zinc can prevent related cancers such as ovarian, breast, and colorectal.
#3 Support Female Reproductive Health and Fertility
In women, zinc is involved in the growth process of the oocyte or egg. If women are zinc deficient, the egg won’t mature properly and ovulation will be impeded, causing infertility. Adequate zinc allows women to use estrogen and progesterone efficiently, supporting reproductive health and ensuring that estrogen does what it’s supposed to do in the body. When estrogen levels become too high, or are inefficiently metabolized they can cause poor reproductive health and breast cancer.
#4 Prevent Cancer and Boost Immune Function
Ananda Prasad, a leading researcher in the field of zinc and health, notes that simply ensuring our zinc levels are adequate can help cure a number of the most severe health problems, especially cancer and poor immune function. Along with prostate cancer, low zinc plays a role in the development of most cancers since it is instrumental in healthy cell proliferation. Recent evidence links zinc deficiency to cancers of the breast, colon, ovaries, lungs, skin, and leukemia.
Zinc deficiency profoundly affects the immune system because low zinc produces a direct and rapid decline in T cell function. T cells elevate the body’s immune system when viruses, bacteria, or challenges to health arise. Older people are at greater risk of zinc deficiency, which is not thought to be solely due to poor dietary intake. There’s evidence that a need for more zinc may increase with age to counter inflammation, support the immune system, and ensure healthy cell function.
#5 Improve Cardiovascular Health
Zinc is vital to maintain the health of cardiovascular cells and the endothelium. The endothelium is the thin layer of cells that lines the blood vessels and plays a major role in circulation. Low zinc can cause a deficiency in the endothelial barrier, which leads to high cholesterol buildup and inflammation. Cholesterol and inflammation increase your risk of heart disease.
Studies show that poor zinc status can amplify the negative cardiovascular effects of a high-fat, high-cholesterol diet, whereas an adequate zinc intake will have a protective effect and inhibit the progression of heart disease. The elderly population is especially susceptible to the buildup of inflammatory markers including C-reactive proteins and cytokines, which have been called “slow, silent killers.”
#6 Become More Sensitive to Insulin and Prevent Diabetes
Zinc is needed for the healthy function of most hormones, including insulin. Adequate zinc plays at least three roles in insulin health. First, zinc binds to insulin so that insulin is adequately stored in the pancreas and released when glucose enters the blood stream.
Second, zinc improves cell health, making up a component of the enzymes necessary for insulin to bind to cells so that glucose can enter and be used as fuel. The process of insulin binding to the cell is what is referred to with the term “insulin sensitivity” and means that the cell is receptive to insulin. Once insulin binds to the cell, it “opens the door” so that the glucose can enter. If the cell is resistant to insulin, glucose will stay in the blood stream, cause high blood sugar, and ultimately lead to fat gain. When zinc concentration falls, there is a reduction in insulin secretion and peripheral insulin sensitivity, which if persistent, will lead to diabetes
Third, zinc has anti-inflammatory effects as mentioned in #5 via its role in abolishing inflammatory markers such as C-reactive proteins. Zinc also helps get rid of substances that cause inflammation in cells, helping to preserve cell health and insulin sensitivity.
A recent study of Spanish school children found a direct relationship between low zinc levels, greater body fat content, and insulin resistance. The children who were classified as zinc deficient had poorer insulin sensitivity and greater glucose intolerance (a related measurement of persistent blood sugar levels) than those whose level was adequate.
#7 Get The Super Antioxidant Effects of Zinc
Zinc is an excellent antioxidant. The purpose of an antioxidant is to get rid of free radicals that cause damage to cells in the body by bonding with them and neutralizing them. Zinc is particularly good at countering the damaging effect of high iron. Zinc also targets free radicals that cause inflammation and is especially effective at detoxifying heavy metals from the brain.
#8 Detoxify The Brain of Heavy Metals and Prevent Alzheimer’s
The super antioxidant effects of zinc allow it to efficiently remove toxins from the body and keep them from building up in tissue and causing damage. The progression of neurodegeneration and Alzheimer’s disease is accelerated by heavy metal buildup in the brain. Zinc can help get rid of those toxins, and it also helps maintain cellular homeostasis of brain cells.
#9 Boost Brain Function and Treat ADHD
Zinc plays an essential role in neurotransmitter function and helps maintain brain structure and health. It is necessary in the metabolism of melatonin, which regulates dopamine. Also, zinc is part of an enzyme that is necessary for the anabolism of fatty acids in the brain membrane. This is very important because a key part of supporting brain health and function is to ensure the membrane gets the nutrients it needs.
A new study on rats tested the effect of giving supplemental zinc to pregnant females during gestation and lactation and found better spatial memory and overall cognitive development in the offspring. A large zinc dose produced the best results. Human studies are limited, but data on how zinc can treat attention deficit hyperactivity disorder (ADHD) indicate its importance.
Zinc is a commonly ignored mineral for treating ADHD. Studies show children with ADHD tend to have lower zinc than healthy children. Even more promising, one study of 400 children with diagnosed ADHD found that taking 150 mg/d of zinc sulfate improved impaired social behavior and made subjects less hyperactive and impulsive than a placebo. Subjects that had higher body mass index and lower fatty acid level had more dramatic improvements in socialization and hyperactivity measures from taking zinc.
#10 Elevate Mood and Avoid Depression
The exact relationship between zinc deficiency and depression is unknown, however it surely has to do with the role of zinc in neurotransmitter and hormone production. Dopamine production, which is partly regulated by zinc status, is a chemical that boosts energy, mood, and reward-driven learning. Poor insulin health or low testosterone levels can lead to health problems that increase rates of depression and low energy. Throw in the antioxidant power of zinc and its ability to get rid of inflammatory biomarkers such as C-reactive protein and tumor necrosis factor (causes cell damage), and it is reasonable to ensure zinc intake is adequate when treating depression.
A new study in the Journal of Affective Disorders showed that zinc deficiency may affect depression in women more than men. Women in this study who were already using antidepressants and had low zinc levels had a five times greater risk of ongoing depression. It’s thought that the gender-based relationship between low zinc and depression is related to how zinc influences energy levels and production of the hormone estrogen.
In women, estrogen is involved in serotonin production—the neurotransmitter that makes people feel good—and zinc supplementation can increase the density of serotonin receptors in the brain. Have you picked up on the theme that zinc plays multiple roles in the body, affecting numerous chemical messengers that play complex, essential, interconnected parts in the body?
How To Test Zinc Level
Before you start popping zinc at random, take note that there is an upper limit to dietary zinc. Zinc toxicity has produced poor immune health and infertility, just as low zinc compromises the immune system. Scientists suggest you perform a zinc test to measure your level and then supplement accordingly. Once you start taking zinc, your levels will rise and you should do another test six to eight weeks later for best results.
The simplest way to test for zinc is a taste test that works because we know that taste and smell are dependent on there being adequate zinc in the body. To do this test, get zinc sulfate and put about 1-2 teaspoons in a cup and sip it, holding it in the mouth. If it tastes just like water, you are very zinc deficient. If you taste something slightly metallic, you are moderately zinc deficient. If it tastes disgusting—strongly metallic and unpleasant—your levels are probably adequate. This test is subject to individual taste perception and it is not 100 percent valid, but it is a good place to start.
Other test options are a serum zinc test, but there are factors that can cause inaccuracies such as fluctuations from meals, stress, diurnal variations, and complications from other nutrient deficiencies. A plasma zinc test is another option and it will pick up severe zinc deficiencies, but it won’t indicate a more moderate deficiency. It should not be relied on because even a moderate deficiency will negatively influence health.
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