During the Covid era we saw an explosion of people using high dose zinc supplements to bolster their immune defenses. Post Covid, this high use of zinc continued with folks becoming somewhat afraid to discontinue.

Cue the Copper deficiency and Zinc induced Anemia. One of the lesser-known side effects of zinc is its ability to interfere with the absorption of other essential minerals, such as copper. Zinc and copper compete for absorption in the body, and too much zinc can lead to a copper deficiency. Copper deficiency then leads to a decrease in ceruloplasmin and subsequent development of anemia.

If you’ve been a chronic Zinc over user and struggling to maintain adequate iron stores – you may well find that your iron levels improve on less zinc because Hepciden (master regulator of iron homeostasis) isn’t being triggered into action.

Yes zinc is an essential mineral, absolutely essential to a thriving body however we really are discounting just how smart nature is and the intelligence of our design. Zinc status is tightly regulated in our body, not too much and not too little. Our body seeks Goldilocks status and it thinks very little of our mega daily doses of Zinc.

‘You can’t fool me’ our biology declares nonchalantly as it shakes its head at our 30mg Zinc supplement being popped yet another day. You see, our body will actually inhibit the absorption of zinc doses beyond 20mg. There is no point in taking a daily high dose zinc supplement because the body will simply reject most of it.

The more replete one’s zinc status, the LESS your body will allow in. The more deficient one is the MORE it will allow in, up to 92% of it will be absorbed vs 16–50%. In a nutshell what this means is that human zinc absorption is more efficient from low zinc diets.

If you want to maximise the bang for buck from your zinc supplement, maybe everyday is not the best approach. Ultimately your body will just refuse to participate and send it down the toilet in your poo. Dose wise what we are talking about here is above that 20mg mark. More than this is just a waste of money when taking daily.

Here’s thing – our body has an inbuilt mechanism to shut down zinc absorption when it is provided in too high amounts. This happens with one other mineral – Iron.

Both Iron and Zinc are tightly controlled and limited by a little something called Hepciden. When either mineral is consumed in too much abundance, the body literally blocks the entry. Hepciden closes down the export of zinc into the blood by down regulating our Zinc Transporter Proteins.

Zinc absorption declines with increased zinc consumption. Bam.

Zinc is the second most abundant micro-nutrient in the human body after iron. The adult human body contains somewhere in the vicinity of 2.6 g of zinc however most papers state this is likely a significant underestimation. Without doing an autopsy on every organ/tissue in the body it is neigh on impossible to accurately gauge.

Overview of zinc distribution and disease association in the human body

We don’t have dedicated storage compartments for zinc in the human body so zinc has to be continuously replenished by dietary intake, but only in logical amounts.  In zinc-deficient states the body puts a halt to fecal and urinal zinc losses and gets way smarter with its use. A healthy adult would expect to loose around 1-5mg of Zinc per day.

In detailed metabolic balance studies in rats, the efficiency of zinc absorption decreased from nearly 100% when a zinc-free diet was fed to less then 55% when 0.5 mg of zinc was fed daily. Each doubling of dietary zinc intake caused a fourfold increase in Endogenous Fecal Zinc Excretion. Basically the body dumps excess zinc into the gastrointestinal tract to have it removed quick stat.

“Four studies compared the response to different levels of zinc intake. When the zinc intake was reduced from 252 to 85 μmol/d in a study of six men (Wada et al. 1985), fractional zinc absorption increased from 25 to 49%. In another study, when zinc intake was reduced from 192 to 63 μmol/d, fractional absorption increased from 44 to 63% (Lee et al. 1993). A study of a reduction to a very low intake (85–12 μmol/d) caused fractional zinc absorption to increase to 93% (Taylor et al. 1991). Doubling the zinc intake from 109 to 224 to 472 μmol/d caused fractional absorption to decline from 47 to 32 to 21%; the LOWER the intake of zinc, the HIGHER the rate of fractional zinc absorption.” – The Journal of Nutrition Volume 130, Issue 5, May 2000.

So let’s use Foraged Wild Zinc as an example of this in practice – 2 capsules delivers 24.9mg of Zinc. Based on what we’ve just learnt above, taking 2 capsules a day wouldn’t be the smartest of use and your body would actually absorb more Zinc if you took it every second or third day. Alternatively, take only 1 capsule daily.

Our BioTrace Organic Zinc provides 15mg per capsule so that’s fine.