Is Metallothionine a Better Marker of Zinc Status Than Plasma Zinc?

Do you want beautiful, flawless, radiantly healthy skin? Want to stay healthy during cold season? Want to eat that bagel without your blood sugar spiking through the roof? Then it's time to think about zinc.

Zinc is critical to every aspect of our biology, but the first things to go when we run low are our skin health, our immune system, and our glucose tolerance. Zinc, moreover, is critical to antioxidant defense, so should be considered broadly protective against all of the degenerative diseases that occur with aging.

Wait, are you too young to care about aging? No problem. You at least want healthy skin, great sex, or a lean physique, so listen up.

Zinc-rich foods are harder to come by then you'd think. Nutritional databases can be wildly inaccurate if you don't adjust for inhibitors of zinc absorption in natural foods. And zinc supplements can be valuable, but they're not a panacea. In fact, used wrongly, they can quickly induce a deficiency of copper and other minerals that are just as critical to your health. 

The show notes can be found at chrismasterjohnphd.com/36. They contain recommendations for specific supplements.

This episode is brought to you by Kettle and Fire Bone Broth. Use the link kettleandfire.com/chris to get $10 off your first order.

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In this episode, you'll find all of the following and more: 

0:00:35 Cliff Notes; 11:40 The discovery of zinc deficiency on diets of whole wheat bread with small amounts of milk and potatoes, a quarter pound of clay, and no meat: dry skin, hypogonadism, lack of secondary sex characteristics, short stature, frequent infections; 17:25 The biochemical and physiological roles of zinc; 19:00 structural roles of zinc, with an emphasis on zinc finger motifs; interactions with vitamins A and D, thyroid hormone, adrenal hormones, and sex hormones 24:07 Catalytic roles of zinc, including the RNA polymerases that make it necessary for the production of every single thing in the body; 26:30 Interactions with vitamin A, from transport via retinol-binding protein (RBP) through activation by alcohol dehydrogenases to retinal and retinoic acid through creating vision via rhodopsin and regulating gene transcription via DNA-binding of the retinoic acid receptor; 29:20 Regulatory roles of zinc 32:25 Zinc and oxidative stress (necessity for hydrogen peroxide production in the thyroid gland and immune phagocytes, zinc release from zinc-thiolate clusters; protective effects of metallothionein exchanging zinc for other metals; negative effects of uncoupling of endothelial nitric oxide synthase [eNOS] on blood vessel function and oxidative stress; 42:45 Regulation at the cellular level (metallothionein, MT; ZIP and ZnT transporters) 44:20 Regulation of metallothionein (metal transcription factor-1 [MTF-1] through the metal response element [MRE] controlled primarily by zinc but also heavy metals, antioxidant response element [ARE] via Nrf1 and Nrf2, which provides regulation by oxidative stress and copper, glucocorticoid response element [GRE] which provides regulation by adrenal hormones and inflammation; 53:40 What happens when we eat zinc (effects of phyate, amino acids, calcium, organic acids, and iron) 1:01:00 Plasma zinc and the exchangeable zinc pool 1:06:00 Factors that affect plasma zinc status (variation according to meals, diurnal variation, stress, inflammation, menstruation) 1:10:25 Causes and effects of deficiency 1:14:20 Variations in soil zinc; 1:15:40 Balance of animal protein and phytate in the diet 1:19:00 Causes and effects of toxicity (especially with respect to copper deficiency) 1:27:20 What is the best marker of zinc status? 1:29:45 Plasma zinc as a marker of zinc nutritional status; 1:37:00 Copper deficiency markers as the most sensitive markers of zinc excess 1:38:10 Dietary strategies (animal foods, especially oysters, red meat, and cheese; soaking, sprouting, and fermenting to neutralize phytate) 1:40:35 Zinc supplementation on a plant-based diet (especially relevant to vegan diets but also to vegetarian diets) 1:42:25 Supplementation of zinc (what form? Citrate, acetate, gluconate, picolinate, oxide? What dose? When to take it?) 1:44:35  Recommendations for timing of diet and supplements across the day for best absorption 1:47:00 Wrapping up

Access the show notes, transcript, and comments here:

https://chrismasterjohnphd.substack.com/p/036-why-you-should-manage-your-zinc