To my chagrin, these lines recently appeared in a leading daily newspaper:
- Korean study reveals zinc rich foods could be the cause for osteoarthritis
- ‘Could seafood and red meat trigger arthritis? Zinc rich foods could cause joint pain, study finds’
- Reducing zinc levels could lead to new therapies for [a] common disease
- Zinc-rich food including seafood, cocoa & chicken could be causing the painful condition osteoarthritis
Two different studies state the opposite:
- Zinc Protects Articular Chondrocytes [cartilage cells] through Changes in Nrf2-Mediated Antioxidants, Cytokines and Matrix Metalloproteinases (Huang 2017)
- Zinc protects chondrocytes [cartilage cells] from monosodium iodoacetate-induced damage by enhancing ATP and mitophagy (Huang 2020)
While the entire newspaper article above implicates zinc as a possible cause of osteoarthritis, the comments section of the same article states that the author of scientific paper in question says ‘No evidence available to date clearly indicated that zinc plays a causal role in osteoarthritis’!!! There’s one big reason why doctors say – never trust Dr Google!
So, is zinc or zinc-rich-food good or bad for you?? Is zinc good or bad for cartilage health?? The short answer – as with anything else, too much zinc (in supplemental form) can be harmful to humans and animals, but sufficient zinc intake is vital for cartilage & much more.
For example, zinc activates > 300 enzymes, and is used in > 3000 human-proteins representing ~10% of all body proteins. Zinc is also vital for communication inside and between cells. By comparison, iron has just 1 one main protein to get iron into cells (DMT1), and one to get iron out (Ferroportin). Zinc on the other hand is so important that it has 14 different import proteins, 10 export proteins and 12 intracellular control proteins (metallothionines).
Mitochondria are cellular organelles, powering all cell processes. They keep cells including cartilage cells healthy. Happy mitochondria ensure chondrocytes make and maintain strong cartilage. The second study above details how scientists can quickly (in a couple of days) induce osteoarthritis by injecting a chemical called ‘monosodium-iodoacetate’ into animal joints. Monosodium-iodoacetate negatively effects 14 separate mitochondrial processes, precipitously lowering energy production, causing chondrocyte damage & death. Chondrocyte death results in inflammation, then cartilage quickly thins, and animals get pain & all other hallmarks of osteoarthritis. In both animals and humans, the likely root cause of osteoarthritis is poor energy production by mitochondria of joint cells.
Zinc supplementation of animals stops all 14 negative effects of Monosodium-iodoacetate, maintains mitochondrial function, and ‘almost completely reverse[s] the effects of monosodium-iodoacetate, suggesting [zinc’s] potential protective role against osteoarthritis progression.
For a person to have great mitochondrial function they need to be getting great nutrition, plus the appropriate hormonal signals from things such as cartilage specific exercise, appropriate sleep and even sunshine. Good cartilage needs the same things. A bad diet, inappropriate and too little exercise, poor sleep and not enough sun, are stressors that can lead to poor mitochondrial function, poor cartilage cell health and osteoarthritis. Zinc is an extremely important nutrient, sufficient intake of which will help prevent osteoarthritis, but it is just ‘one of many’ things that together as a team will support excellent joint health. The best source of zinc is oysters at 70mg per 100g.
Article Written + Submitted by:
Andreas Klein Nutritionist + Remedial Therapist from Beautiful Health + Wellness
P: 0418 166 269