Zinc is one of the most important dietary minerals that our body needs because it supports a lot of important functions in the human body. Zinc, like other important minerals such as magnesium, contributes directly in the activity of the enzymes. There are more than 300 enzymes that depend on zinc.
Roles and Benefits of zinc in our body
- Immune Function: Zinc is key to proper T cell and natural killer cell functions that helps boost our immune system by producing antibodies to fight infections. It fights off colds and sore throats and recovers from injury, illness, or surgery. It also helps in chemical detoxification.
- Skin Health: Zinc helps in healing wounds faster and maintains our skin healthy. According to a research done to young men by feeding them with foods low in zinc it caused some skin related health problems like acne, facial rash and foot fungus.
- Sexual Health: Zinc helps with growth hormone production as well as sex hormones. Having infertility, low sperm count, reduced testosterone levels, or prostate issues are some of the zinc deficiency symptoms in men. This type of health issue is usually encountered at an advanced deficiency of zinc. In folklore oysters & chocolate are an aphrodisiac, probably because both contain large amounts of zinc, especially oysters!
- Sensory Functions: Zinc help maintain our sense of taste and appetite in good. A study have showed that 15% of elderly people who lost their sense of taste was due to zinc deficiency. If you loss the sense of taste for a while, you should report this to your doctor as this may be one of the zinc deficiency symptoms.
Zinc is also critical in our vision. Though there is no evidence that age-related vision loss is due to zinc deficiency, there is a study that has shown that zinc levels in the retina decline in tandem with vision loss.
Common symptoms of zinc deficiency
Aside from the warning signs and symptoms of zinc deficiency mentioned above, here are some of the lists you need to check out if you are low with zinc:
- Bad breath
- Behavioral and psychiatric issues
- Connective tissue disease
- Delayed sexual maturation
- Fatigue
- Females could have menstrual issues
- Growth retardation
- Hair loss
- Impaired senses of smell and taste
- Infertility
- Inflammatory bowel disease
- Mal-absorption
- Males could also have prostate issues or testicular atrophy
- Males could have low sperm count, reduced testosterone levels or impotence
- Oversensitivity to environmental toxins
- Poor appetite
- Poor glucose tolerance
- Poor memory
- Poor vision at night or with low lighting
- Rheumatoid arthritis
- Skin lesions and skin issues, including eczema, psoriasis and acne
- Sleep issues
- Ulcers in the mouth
- White coating on the tongue
- White spots on the fingernails; the nails could be thin and could peel
Common Foods High in Zinc
Foods rich in zinc are meat; especially red meat, fish, poultry, and other seafood (shellfish especially). Oysters contain the highest zinc per serving than any other food, . Plants are also rich in zinc since they naturally absorb zinc from the soil, but plant-based foods specifically phytates are in general provide lower zinc to your diet due to dietary fiber and phytic acid which inhibits the absorption of zinc.
Here is a list of some foods containing Zinc broadly sorted from higher % of Zinc per gram of food to less:
- Seafood – particularly shellfish such as oysters, shrimps, crab and lobster
- Leafy greens – spinach
- Seeds – pumpkin, sunflower, chia and flaxseed
- Nuts – cashews, pine, pecans, almonds, walnuts
- Cocoa – dark chocolate (one of my favorite source of Zinc, get some high % chocolate, ideally 70%+ but I tend to get 85-90%)
- Mushrooms – shitake and crimini mushrooms
- Meat – Especially organ cuts such as liver from beef, lamb, pork, turkey and chicken
- Vegetables – beans, peas, broccoli, sprouts and tomatoes
- Eggs
- Avocados
- Garlic
The current recommended dietary allowances as per the Office of Dietary Supplements. for zinc are 11mg for males and 8mg for females above the age of 19.
Using Zinc supplements
While a lot of the food you eat might contain trace amounts of Zinc, unless you eat shellfish type food or organ meats (liver) you are probably deficient like me on the days you do not (cronmeter is an easy way to find out). Also, according to Dr. Mercola, nowadays zinc has become harder to be absorbed by our body due to genetically engineered crops that contain Glyphosate. Finally, if you do not eat either of those on an almost daily basis, you probably want to supplement with some low dose Zinc supplements of around 15mg. Zinc is very cheap and you will often see it in high doses of 50mg. If you take such high doses, be careful of not taking them on a constant daily basis… To make sure you get the best zinc supplement in terms of absorption, be sure to choose the chelated form of zinc as these are better absorbed. I personally prefer the “picolate or citrate” forms
Side Effects of Zinc overdosing
As long as you don’t exceed the upper tolerable intake levels of 40mg, you are probably safe from the bigger side effects of zinc supplementation, as per this table taken from the Office of Dietary Supplements. However, as I mention in my article on why you do not want to use a multivitamin, taking too much Zinc is more of a problem in how it will compete with other minerals to be absorbed by your body, such as copper. Also, in a similar mindset, if you take iron supplements, it will reduce how much zinc your body absorbs (or in a multivitamin, make the zinc that comes with Iron less useful, once again why you do not want to use a multivitamin!).
So to sum up potential zinc overdose symptoms & problems:
Higher intakes may cause: nausea, vomiting, cramps, discomfort, metallic taste in mouth, headache, and drowsiness. It can also impair the absorption of other nutrients essential to the body.
Sources:
http://www.whfoods.com/genpage.php?tname=nutrient&dbid=115
http://www.dummies.com/how-to/content/zinc-the-immune-system-nutrient.html
http://www.naturalnews.com/044633_zinc_nutritious_foods_mineral_deficiency.html
http://alanaturale.com/real-food/foods-that-contain-zinc/
http://articles.mercola.com/sites/articles/archive/2013/10/17/alzheimers-zinc-deficiency.aspx
http://articles.mercola.com/sites/articles/archive/2012/12/13/zinc-for-colds-and-flu.aspx
http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/