When it comes to the best dosage of ascorbic acid supplementsit helps to understand how the nutrient is absorbed by the body.
“We have transport proteins in our small intestine that regulate how much ascorbic acid can pass through the gut [and] into the bloodstream, “explains Michels. And while there are multiple transport proteins that regulate how much ascorbic acid can cross over, they all become flooded when you take more ascorbic acid than they can handle (about 400 milligrams), he says.
As a result, “the rest of that vitamin C just gets pushed through your gastrointestinal tract and is lost [in the urine]”notes Michels. What a bummer.
Fortunately, it is possible to maximize your blood concentrations of vitamin C. If you’re taking pure ascorbic acid (ie, more than 300 to 400 milligrams per serving), the best plan is to break it up into two or three doses and spread them out throughout the day.
“This way, the transport proteins have [a lower] chance of being overwhelmed, and more vitamin C will get through the bloodstream, “says Michels.
It’s worth noting that most scientific studies, especially those on the link between vitamin C and immune function, involves doses at 500 or 1,000 milligrams — and sometimes higher. So, for higher doses, you’ll want to be extra mindful of the type of vitamin C in your supplement so you can optimize absorption.
That’s why mindbodygreen’s vitamin C potency + uses a clinically researched and highly bioavailable combo of vitamin C (a 1,000-milligram dose, to be exact), lipids (fatty acids from rice bran), and citrus bioflavonoids (phytonutrients from bitter orange). * So it’s a complex or trio, with C as the leading actor, and the lipids plus citrus bioflavonoids as the supporting actors.
When taken together, the lipids help vitamin C move through lipid membranes, while the citrus bioflavonoids help buffer the C from oxidation. * For the record, this translates into a 233% higher cellular absorption rate of vitamin C compared to pure ascorbic acid. * †
The upper limit of vitamin C is 2,000 milligrams a day (as per the National Academies), meaning it’s totally safe for most adults to take up that dose of vitamin C every day.
In fact, a Free Radical Biology & Medicine study found that higher doses of vitamin C can deliver additional health benefits—But be sure to get the green light from your health care provider before starting a high-potency vitamin C supplement. *