I'm sure many of my readers and patients take Vitamin C every day. There are many competing Vitamin C products out there and what do you look for in picking one? Vitamin C is ascorbic acid, found primarily in citric fruits but also found in corn, beets, and sago palm. The majority of the Vitamin C appearing on store shelves is made from corn and over 90% of the world's supply is manufactured by Hoffman La Roche, one of the largest pharmaceutical companies in the world. So no matter what brand you buy, if it is corn derived Vitamin C, chances are it came from HLR.
There is some concern that if you have a corn allergy, then corn-based vitamin C may bother you. I have never seen this in any patient, but it may still be a consideration in picking a product.
Taking pure ascorbic acid can give you some stomach acidity so many C products are buffered, often with calcium and magnesium salts. This takes up space and you will have to take more capsules to get the same dose of Vitamin C. For example, a teaspoon of pure ascorbic acid powder can contain 4000 mg of Vitamin C. One teaspoon of buffered Vitamin C powder will only contain about 1000 mg. of Vitamin C.
How does Vitamin C get absorbed? There is a specialized transport system in the GI tract which picks up Vitamin C and takes it into your blood stream. This system has a maximum load it can manage and when you have saturated this system, then all remaining Vitamin C you have taken goes out. This can lead to one of the common side effects of excess Vitamin C, namely loose stools.
Research at NIH, The National Institutes for Health, by Dr. Mark Levine, has shown that no matter how much oral vitamin C you swallow, there is maximum blood level you can attain which is lower than that achieved with intravenous administration. He found that giving 10 grams (10,000 mg) of Vitamin C IV results in a blood level 25 times higher than taking the same dose orally. The GI transport system likely saturates at oral doses of 3-4,000 mg daily.
What about ester C - a new player on the block? There is no independent evidence to show that this C is absorbed any better than plain old Vitamin C powder. So save your money.
The cheapest form of Vitamin C is still the pure ascorbic acid powder. This can be bitter to swallow as a powder as it is acidic. It can be mixed wih juice. One teaspoon will contain 4000 mg of pure Vitamin C. One pound of pure Vitamin C powder will supply 454 doses of 1000 mg for a cost often below $30.
Vitamin C is excreted by the kidney fairly quickly. So I always advise patients to take Vitamin C in at least two divided doses daily, one with breakfast and one with supper so as to maintain levels of vitamin C more evenly throughout the 24 hours.
What about Vitamin C and the common cold? Many people, including me, take Vitamin C daily to "ward off a cold". The evidence shows that Vitamin C will shorten the duration of cold symptoms but it is not clear if taking Vitamin C daily will actually reduce your chances of getting a cold virus from someone else.
What about kidney stones and Vitamin C? Opponents of Vitamin C (and there are many), contend that taking high doses of Vitamin C can produce kidney stones. I would respond with "show me the beef". There are no published cases of kidney stones occurring with high doses of Vitamin C in the world medical literature that I have found.
drBob
I'm sure many of my readers and patients take Vitamin C every day. There are many competing Vitamin C products out there and what do you look for in picking one? Vitamin C is ascorbic acid, found primarily in citric fruits but also found in corn, beets, and sago palm. The majority of the Vitamin C appearing on store shelves is made from corn and over 90% of the world's supply is manufactured by Hoffman La Roche, one of the largest pharmaceutical companies in the world. So no matter what brand you buy, if it is corn derived Vitamin C, chances are it came from HLR.
There is some concern that if you have a corn allergy, then corn-based vitamin C may bother you. I have never seen this in any patient, but it may still be a consideration in picking a product.
Taking pure ascorbic acid can give you some stomach acidity so many C products are buffered, often with calcium and magnesium salts. This takes up space and you will have to take more capsules to get the same dose of Vitamin C. For example, a teaspoon of pure ascorbic acid powder can contain 4000 mg of Vitamin C. One teaspoon of buffered Vitamin C powder will only contain about 1000 mg. of Vitamin C.
How does Vitamin C get absorbed? There is a specialized transport system in the GI tract which picks up Vitamin C and takes it into your blood stream. This system has a maximum load it can manage and when you have saturated this system, then all remaining Vitamin C you have taken goes out. This can lead to one of the common side effects of excess Vitamin C, namely loose stools.
Research at NIH, The National Institutes for Health, by Dr. Mark Levine, has shown that no matter how much oral vitamin C you swallow, there is maximum blood level you can attain which is lower than that achieved with intravenous administration. He found that giving 10 grams (10,000 mg) of Vitamin C IV results in a blood level 25 times higher than taking the same dose orally. The GI transport system likely saturates at oral doses of 3-4,000 mg daily.
What about ester C - a new player on the block? There is no independent evidence to show that this C is absorbed any better than plain old Vitamin C powder. So save your money.
The cheapest form of Vitamin C is still the pure ascorbic acid powder. This can be bitter to swallow as a powder as it is acidic. It can be mixed wih juice. One teaspoon will contain 4000 mg of pure Vitamin C. One pound of pure Vitamin C powder will supply 454 doses of 1000 mg for a cost often below $30.
Vitamin C is excreted by the kidney fairly quickly. So I always advise patients to take Vitamin C in at least two divided doses daily, one with breakfast and one with supper so as to maintain levels of vitamin C more evenly throughout the 24 hours.
What about Vitamin C and the common cold? Many people, including me, take Vitamin C daily to "ward off a cold". The evidence shows that Vitamin C will shorten the duration of cold symptoms but it is not clear if taking Vitamin C daily will actually reduce your chances of getting a cold virus from someone else.
What about kidney stones and Vitamin C? Opponents of Vitamin C (and there are many), contend that taking high doses of Vitamin C can produce kidney stones. I would respond with "show me the beef". There are no published cases of kidney stones occurring with high doses of Vitamin C in the world medical literature that I have found.
drBob