[EvaH (OP)]

Mike and Pauline ask:

As believers and consumers of vitamin supplements, we are wondering if there is likely to be any conflict between the covid vaccine and vitamin C?

Can you help?

[Bored chemist]

If you, or your healthcare provider, is spending money on vitamin C then you can't spend it on treating covid.

[evan_au]

Prevention is better than cure.

Effect of Vaccination
If we continued with air travel, and had no COVID vaccine, everyone would eventually get COVID-19, and 1-2% of people would die from it.
- A vaccine is a good preventative measure (and until the vaccine is deployed, masks, social distancing, handwashing and quarantine can hold it at bay)

Effect of Vitamin C Supplementation
A therapeutic dose of vitamin C is above 10mg per day, or about 1 orange or 1 kiwifruit per week. This is for someone who is already suffering the disease scurvy.
- You need less than 10mg per day if you don't have the disease, and your internal stores of vitamin C take a month to get depleted. So 1 orange per week will prevent the disease.
- If you went a few months with no fresh fruit (like some early sea voyages), you would start showing symptoms after a month, and would have a small chance of dying after 2 months
- So eating some fruit is excellent prevention! (see list at the link below.)
- If you really can't get any fruit (eg you are living in a nuclear submarine and the fridge isn't working), a typical vitamin C pill has 1000mg (1 gram) of vitamin C. You could break it into 100 pieces (1 piece per day); 4 pills would last a year.

Interaction of COVID Vaccine & Vitamin C Supplements
The main interaction of the vaccine and Vitamin C sales is that, with the vaccine, the number of people alive to pay for Vitamin C pills will be 1-2% higher.
- Only, the people who believe "you need 1000mg of vitamin C every day" overlap considerably with the people who think that "during vaccination, the nurse will implant a computer chip designed by Bill Gates to control your brain via 5G", and they won't get vaccinated.

https://en.wikipedia.org/wiki/Scurvy#Prevention