From a Carnivore Diet Forum:
Colleen Bee writes:
Here is what I found on Dr. Axe: (Please note the risk of kidney stones hence the reason I would avoid plant foods high in oxylates and that can cause cancer).
I binge watch carnivore doctors, nutritionists so I must have heard the shorten of lifespan from one of them. And, according to Dr. Thomas Seyfried cancer is cell division out of control and oxidative stress is also a risk.
Vitamin C Overdose Dangers and Complications
In rare instances, such as in some cases reports, serious adverse reactions/side effects of vitamin C overdose have been found to include:
- Kidney stones
- Increased oxidative stress
- Excess iron absorption
- Vitamin B12 deficiency
- Erosion of dental enamel
- Birth defects
- Cancer
- Atherosclerosis
- Rebound scurvy
Reply by Dolev Gilmore:
Kidney stones: The research shows otherwise. If anything, vitamin C has been found to eliminate stone formation.
Oxidative stress: In cancer cells, vitamin C produces hydrogen peroxidase, and cancer cells don't have catalase to neutralize it. The oxidative stress damages or kills the cancer cells. Doesn't happen in regular cells. Other than that, how can he say such a thing? Vitamin C is well known as a vital antioxidant.
C helps non-heme iron absorption (meaning, from plants. "Excess" doesn't happen, except possibly in cases of hemochromatosis. But carnivore humans don't have to worry, since the iron is heme and vitamin C doesn't increase absorption.
B12 deficiency: Based on a terribly designed study somewhere around 1978, which was disproven a couple years later. Anyone researching this will easily find refutation.
Erosion of dental enamel: it's a concern if drinking it from powder in water. Those doing so should rinse their mouth after. Otherwise, no problem.
Birth defects: Bullsh*t.
Cancer: the opposite is true. It prevents and treats at high enough doses.
Atherosclerosis: What? Give me a possible process. Matthias Rath wrote a book called "Why Animals Don't Get Heart Disease", explaining that mammals make a whole lot of vitamin C in their livers, which prevents weakening of collagen in the arteries, which prevents the cracking which is patched up by cholesterol and fats. Also books by Owen Fonorrow and Dr. Thomas Levy show that vitamin C prevents atherosclerosis.
Rebound scurvy: a possible problem for people taking high doses, then getting hospitalized and having the doctors stop the vitamin C. People should take vitamin C every day of their lives.
Anyone making claims against vitamin C must explain why other mammals do not have all these problems, while they make multi-gram doses of vitamin C in their livers and inject it 24/7 into their bloodstreams, while increasing production to deal with any stress.
Dr. Axe obviously has an axe to grind.
I have heard that people that are living on a high carb diet would require significantly more vitamin C than carnivore diet as we don't have to worry as about extreme loads of oxalates. Unfortunately I do not remember the source (probably a podcast) or every detail of the particulars, but I was wondering if our vitamin requirements and thresholds would be significantly different from Carnivore vs Keto vs Vegan/Veg vs SAD etc. as each are different impacts and benefits to our systems. The problem with a single nutritional vitamin requirement standard doesn't account for the infinite ways we live and eat nor the environments that impact us.
Corey, your comment is very thoughtful, and it is cetain that different diets and many other factors affect the nutrient needs. It's called Biochemical Individuality, and there is a classic book by that name written by Roger Williams. You are totally correct about single requirement standards, but every human needs to take what people on this forum would consider high doses of vitamin C, because of our mutated gulanolactone oxidase gene, which in mammals is the final enzyme converting glucose to vitamin C. I've never prescribed less than 1,000 mg of vitamin C twice daily to anyone 12 years of age or older.
