Vitamin C should be manufactured by an FDA approved factory. It should always be manufactured to British, American & European Pharmacopoeias. Country of origin has no bearing whatsoever on the product, providing it meets this criteria.
Sometimes the public are misled into believing that there is “a better or purer” form of Vitamin C than what we have just mentioned. This is absolutely impossible and is usually said by small unregistered companies looking to make huge profits from vulnerable people. We regularly see companies selling Vitamin C powder at ridiculously highly inflated prices, for a product which is the same as ours or inferior to ours. There are numerous bogus companies making false claims and huge profits.