Zinc – Necessity or Nauseating?
Nothing hits home like our own experiments. My ‘case study’ (which I say tongue-in-cheek) alerted us to significant caution by the fourth ‘trial’ session. My ‘case study’ included myself and my husband, in which we tracked and learned about our own reaction to zinc lozenges.
The Cold-Zinc Connection
Why is zinc commonly taken? The Mayo Clinic, along with most health care sources recognizes evidence that zinc can reduce the length of colds. When lozenges (or syrup) are taken within 24 hours of cold symptoms starting, it can reduce the number of days you suffer with discomfort, or perhaps the degree of that discomfort.
Common, too, is the warning that internasal zinc (spray) has evidence suggesting it is linked to loss of smell. We can’t take this lightly as it can be long-term.
Suspected colds are the reason why I have a case study to report on. Unfortunately, people often have allergy symptoms mimicking a cold and the extra heap of zinc may be of little use. I will report my ‘findings’ later.
Most importantly, we need zinc more than “for a little cold.” And as we age, a “little cold” can take its toll.
What does the Body do with Zinc?
Zinc is considered an essential trace mineral; it’s “essential” to help make other helpful substances. It’s also essential that we consume zinc as the body doesn’t manufacture its own. As with many essential minerals, we don’t need a lot of zinc. Still, what we need it for is impressive. It isn’t the only substance that controls or benefits these actions, but here is a partial list (in no particular order) of how our body uses zinc.
|Aids digestion and metabolism||Helps wound healing|
|Boosts immunity & helps immune system||Protects against eye disease|
|Combats inflammation (slightly)||Benefits bone building|
|Maintains prostate glandular activity||Aids maintenance of Vit E in the blood|
|Ensures full benefits of amino acids,
our body’s building blocks
(as do other vit/minerals)
|Functions as a component of Insulin|
Not Enough Zinc
Zinc is an element in more than 100 Enzymes.
If we’re not getting enough zinc from our food (or supplement), the reactions are in direct comparison to the beneficial actions above. Rarely would the reduction of zinc be the total cause of disease or problems, but still adds to the burden. Reduced zinc can lead to:
|Chronic Fatigue||Prolonged Healing|
|Nerve dysfunction||Irregular menses|
|Poor development (growth)||Delayed sexual maturity|
|Loss of taste/appetite||Diabetes|
Synergy is well acknowledged (although not totally understood) in the world of literature on bodily nutrients. Luckily for us, balanced diets most often balance our nutrients. But then, many of us believe we eat a balanced diet until we start recounting what was on our plate and went into our mouths. (Me too.)
Zinc works both with, and because of, other substances. A short list includes some of these pairings.
- Copper, which aids formation of red blood cells and connective tissue (along with Vit C), needs zinc to work. A typically-suggested ratio of zinc to copper is 10:1 (zinc 10x more).
- Vit A is most effective when amalgamated with others, consider synergistic links between vitamins D, K2 and A and zinc.
- Vit E in the blood is maintained at proper levels by zinc.
- SOD (Superoxide Dismutase), a strong antioxidant, helps the body utilize zinc. Thus, zinc is sometimes lauded as having antioxidant properties. SOD, by the way, is manufactured naturally in the body (from foods like broccoli, cabbage, Brussel sprouts, grasses and sprouts, and many green plants). Manufacturers may disagree, but nutritionists would most likely tout food sources over supplements.
Interference is a 2-Way Street
Balance and cooperation are clear when considering the ‘Zinc Friends’ above. At other times, there is more a foe, and less friendly, relationship with zinc.
My personal opinion is that anything over 150 mg/day is “excessive,”
not just high, but excessive.
Unwarranted amounts of zinc (usually via supplements) can interfere with iron absorption. Thus, those with anemia tendencies may need to watch levels in a supplement, or excessive zinc-rich foods (see below). The anemia issues may be less about iron (or zinc) and more about copper deficiency association with anemia. Undue amounts of zinc are much more often associated with supplements.
More often it is inhibition of zinc that is at issue. This can be from foods and drink, supplements or medications.
Excessive fiber can reduce zinc – or inhibit its action. Truly it has to be a bit of overkill, and most of us probably need more, not less, fiber in our diets.
Here we see another fine-line relationship. We need to incorporate some circular thinking about the interaction of phosphorus and zinc in the body. Stay with me.
Consumption of large amounts of unnecessary daily junk food and sugary soda will increase phosphorus. Phosphorus works with calcium to build strong bones and teeth, stimulates muscular contraction and is needed for nerve transmission. But too much phosphorus will inhibit calcium uptake, one player in avoiding osteoporosis. Zinc metabolizes phosphorus and keeps the calcium uptake sufficient, but zinc may not succeed when the diet produces too much phosphorus from those sweet sodas and junk food.
(Congrats to you if you followed me all around that circle. Guess it could have been summarized by saying ‘avoid too much junk food and soda.’)
Drug Reactions and Foes
Many pharmaceutical drugs have contraindications with other drugs, food and herbal or nutrient supplements. Some can deplete the body of the same nutrient you are paying for in your supplement.
There may be more, but here a few common drugs that alter zinc levels:
- For infection and Antibiotic use (i.e., Tetracycline or Quinolone)
- For Allergies and inflammation (Cortisone)
- For High Blood Pressure (some Thiazide diuretics) can cause more zinc to be lost through urine. See What to Know about Blood Pressure Medications for YOU or a Loved One — (a Primer) — Aging with Pizzazz )
Conversely, zinc can reduce the effective action of Penicillamine (Rheumatoid drugs), such as Cuprimine or Depen.
I already noted that I believe 150 mg/day or above to be excessive. Then what amount is not overdoing it?
Common recommendations for adult zinc doses are 8-11 mg/day. The lower levels for women, upper for men. National Institute of Health, and Tuff’s professor Junaidah, list the upper level of daily use as 40 mg.
My previous multi tab had no zinc; my current one includes 4.5 mg (as zinc citrate), an amount which would almost certainly not have side effects. Additionally, I eat lots of nuts, seafood and plant food, so with my level of phytonutrients, I don’t give too much thought to needing zinc.
Zinc by any other Name?
I should mention here, that you may notice that there are several kinds of zinc in supplements. Two most common types are “Zinc Citrate” and “Zinc Gluconate” (the difference is their parent compound). Citrate is generally noted as having more side-effects (metallic taste, upset stomach and more). Gluconate has fewer side-effects (one being anosmia – loss of smell), and tends to be slightly more expensive. Both work comparably.
For seniors, moderately high levels of zinc (i.e., 60 mg/day for a few months) has been shown to reduce copper (important to numerous enzymes). Other research demonstrated that at higher levels of 80 mg/day (taken as zinc oxide), it can lead to eye disease in older groups (Age-Related Eye Disease Study – AREDS). While one might not pick ‘the oxide’ flavor of zinc (ok, it really doesn’t have flavor), it did take the subjects many years (over 6) before suffering with this condition.
(Zinc oxide used topically to prevent sunburn is the same substance as mentioned above. However, there doesn’t seem any concern of over-absorption through the skin that I have found to date.)
My Cold Products
I have two products which were the foundation of my case study. One contains a combination of zinc citrate and gluconate at 23 mg (it also contains Echinacea and extra Vit. C). The other product is a 50 mg chelated zinc gluconate.
Neither of these substances should be taken for more than a few days. I would certainly not take them more than 7 days, no matter my symptoms. Still, this type of zinc lozenge may work to reduce symptoms in some cases. Enough so to consider them.
Food Sources of Zinc
Hopefully, I’ve made it clear that this trace mineral is essential to us. Further, “over” consumption of zinc when obtained from phytonutrients in food is rare and has little draw-back. We can’t always say the same for supplements.
I doubt that any of us, certainly not me, can remember little details of what foods are rich in which substances. I can’t remember it, and I’ve studied it. Furthermore, I don’t care. What’s important to remember is consuming a good balanced diet, and possibly only using zinc supplementation on a rare occasion.
Nevertheless, to prove my point of how many good zinc-rich foods there are, here’s a partial list of some.
My Case Study
Here’s the deal from my POV. When taking high doses of zinc (like my 50 mg lozenge), as a minimal precaution – do NOT consume it on an empty stomach.
My husband and I have repeatedly felt nauseated (sometimes accompanied by indigestion) when turning to a zinc lozenge before a suspected cold. Fortunately, (or unfortunately for my research), the majority of those times we never got a cold. Thus, it’s hard to know if it was useful or not.
Unlike a kiss to a skinned-knee that “makes everything all better,” I would not jump to the conclusion that the zinc halted our colds. It is more likely that these events were following a hard day of pollen or outside allergy connections.
Worse along the lines of unknowns is that admittedly, I forgot to note which of my two lozenges was taken when. Did they both cause nausea? Who know? Frankly, I’m not in a rush to suffer signs and symptoms again in order to test my hypothesis further.
Other people have been known to suffer headaches, diarrhea and vomiting with high doses of zinc. To me, this indicates that if we’re smart, we don’t want to take these lozenges as a candy-substitute.
For me, I will stick to an adequate diet, pick multi(s) with low amounts of zinc and make certain I have a full stomach whenever taking a moderately-high-dose zinc lozenge. Better yet, would be not to feel cold symptoms coming on, but hey, we can’t have everything.
Since I was including him in my recounting,
I asked my husband if he thought I should try to end this
rather dry post with a joke?
He said “I don’t zinc so.”
Picture credits: Zinc- Periodic Table of Elements by Science Activism – marked as CC BY 2.0
Premo zinc yellow – cobalt blue – fuschia by It’s_all_about_color_ marked as CC BY 2.0