How much vitamin C do we really need?
The RDA for vitamin C is set at 90 mg per day for men and 75 mg per day for women. In addition to supporting immune function, this vitamin improves heart health, is a building block for collagen necessary for skin, gastrointestinal, and joint health, and has been shown to kill certain cancer cells, among other functions.
Also, in addition to getting vitamin C from food sources, you can take it orally in supplement form or give it intravenously. How you get it determines how much you need. When taken orally, which is typically how most of us get it, intestinal absorption, among other factors, determines how much is actually concentrated in the blood. It’s also important to note that stress depletes vitamin C and who isn’t stressed these days? Taken intravenously it prevents digestion and absorption is more effective.
According to cardiovascular research scientist and Pharmacy Ph.D. James DiNicolantounio, optimal doses can be as high as 1,250 mg twice daily, and while even 2.5 grams daily doesn’t necessarily produce complete saturation, it can still have benefits.
Keep in mind that vitamin C is a water-soluble vitamin, so it is not stored in fat cells. That is why it should be taken daily. Also part of what you take is excreted. Research has shown that the bioavailability was effective and complete for a single 200mg dose. dose. In those tested, vitamin C was not excreted below 100 mg. dose. Therefore, it was concluded that the minimum effective dose should be 200 mg daily. The optimal dose will probably be much higher.
For example: you would need to take 1250 mg. of vitamin C twice a day to reach 80 μm (μm represents the concentration in the blood); and 5 grams (5,000 mg) per day to achieve 250 μm. Therefore, even taking 2.5 grams a day does not necessarily result in fully saturated blood levels of vitamin C. It is also important to note that it is more effective to take it in divided doses throughout the day rather than one large dose for best results.
Years ago I had a bioimpedance test which revealed that my body needed much more vitamin C than it was currently taking. And I thought I was taking too much! Increase my intake in divided doses to 4000 mg. daily has helped me control some serious gum problems. When I’m fighting a cold or exposing someone who is, I usually up it to 1000mg. per hour throughout the day for one or two days.
Many naturopathic doctors recommend taking vitamin C throughout the day until you reach intestinal tolerance, that is, until you start to experience diarrhea, and then slightly reduce the effective amount for you.
My suggestion is that you pay attention to your body and use vitamin C on a daily basis. It doesn’t store, so you won’t overdose like you can with fat-soluble vitamins. Particularly during cold and flu season, it’s important to get enough of it on a daily basis.