“Vitamin C is absorbed in the small intestine where there is a group of different proteins that it can absorb,” Michelle explains. It’s easy enough – so what’s the problem with vitamin C absorption?
Well, there is a form of vitamin C (and many supplements) in food called ascorbic acid. According to Mitchell, the potential challenge with ascorbic acid (high levels) absorption is that it is easily saturated – take concentrated amounts of vitamin C at a time in this form and you are not likely to absorb excess.
However, there are important differences: when the gut is exposed to low levels of ascorbic acid (i.e., less than 400 mg), an active transport system absorbs vitamin C (i.e., carries nutrients through the gut and into the bloodstream, where This is what the body needs).
As soon as these active transports are overwhelmed, the passive diffusion begins to absorb the rest of the vitamin C (which is a fairly ineffective process). The truth is that absorption is not as easy as it may seem, and the fact is that there seems to be a limit to the absorption of ascorbic acid, which can make it difficult to reap all the benefits of high potency sources (if they feature the ascorbic acid form).
Also, Vitamin C is soluble in water, which means it dissolves in water (as the name implies), but this type of vitamin cannot be stored in your body for later use.
You may become more familiar with the process of fat-soluble vitamins – including D, E, A and K – which are absorbed and stored in tissues. Alternatively, extra water-soluble vitamins are eliminated, which allows you to start fresh every day.
Your body can control about 300 to 400 milligrams of pure ascorbic acid form vitamin C (which is a really beneficial, low-dose, multivitamin and other multi-ingredient complex) at a time, but higher doses are less absorbed, according to Michelle.
“It’s more than enough to absorb most of the vitamin C you get from food, but supplements can be a different story,” he explained. Due to the saturation phenomenon, the residue of that valuable vitamin C from an ascorbic acid supplement will, for example, theoretically be flushed down the toilet (i.e., you will urinate it).