Can You Take Vitamin C Supplements With A Multivitamin?

Hello and thank you for your question!

You don't mention in your question exactly which multivitamin and vitamin C (ascorbic acid) supplement products you are looking at, so I'll answer this in a general sense.

For the vast majority of individuals, it's certainly safe to take a multivitamin containing vitamin C, along with a stand-alone vitamin C product.

I'll discuss more regarding vitamin C dosing in the next section, and how much vitamin C over the counter products generally contain, but it's important to note here that vitamin C is extremely well-tolerated, at a wide range of doses, and it's essentially impossible to overdose on it.

Now, there are recommendations on dosing for vitamin C, and a published 'tolerable upper intake level' (referred to as UL) for the vitamin, but there are more than a few studies that show taking high doses (even 'mega-doses') causes little, if any, harm (aside from perhaps some gastrointestinal issues and other rare, unconfirmed side effects).

Vitamin C is a water-soluble vitamin and if you consume more than your body can absorb, the excess is simply excreted in the urine, so most individuals don't have to worry about taking too much.

Vitamin C Dietary Recommendations

The recommended dietary allowance (RDA) of vitamin C varies per person.

For adults, the following are the recommendations set by the Food and Nutrition Board (FNB) at the Institute of Medicine (IOM):

• Adult women (aged 19 and older): 75 mg per day
• Adult men (aged 19 and older): 90 mg per day

Most vitamins and minerals also have a defined 'Tolerable Upper Intake Level (UL)', which is defined as the maximum daily intake unlikely to cause adverse health effects.

For Vitamin C, this amount is set at 2,000 mg per day.

Vitamin C In Multi-Vitamins & Supplements

Most multivitamins contain 45-200mg of vitamin C per serving while most stand-alone vitamin C supplements contain between 500-1,000mg per serving (although of course, this can vary).

Below, I've got the 'supplement facts' label for several popular multivitamins and stand-alone vitamin C products, from popular brands such as One-A-Day, Emegen-C, and Nature Made.

Here is a 'One A Day Men's' multivitamin that contains 99mg vitamin C per serving:

This Nature Made product contains 180mg vitamin C per serving:

Stand-alone vitamin C supplements almost always contain more vitamin C than what is contained in a multivitamin. As mentioned, this amount is usually between 500-1000mg per serving.

Below are the 'supplement facts' labels for two popular stand-alone vitamin C products, Emergen-C and Garden Of Life Raw Vitamin C.

This Emergen-C supplement contains 1,000mg vitamin C per serving:

One serving of Vitamin Code Raw vitamin C contains 500mg of vitamin C.

With the vast majority of multivitamin and vitamin C supplement products, even taking both together, you generally will still be under the recommended upper limit of vitamin C (which again, is 2,000mg).

For example, if you took one serving of the Nature-Made multivitamin and one serving of Emegen-C, that would only equate to 1,180mg of vitamin C.

Too Much Vitamin C?

As mentioned at the beginning of this answer, vitamin C is an extremely safe vitamin.

A number of studies have shown taking doses that far exceed the recommended upper limit of 2,000mg generally results in only mild (if any) side effects.

There have been some studies that linked consistent, daily, high doses of vitamin C with an increased risk of kidney stones, but the evidence for this is far from conclusive.

The National Institute of Health states the following regarding high doses of vitamin C:

Vitamin C has low toxicity and is not believed to cause serious adverse effects at high intakes. The most common complaints are diarrhea, nausea, abdominal cramps, and other gastrointestinal disturbances due to the osmotic effect of unabsorbed vitamin C in the gastrointestinal tract.

One of the reasons that vitamin C is so safe is that it is a water-soluble vitamin, and any excess that we do not absorb is excreted when we go to the bathroom.

In fact, even though vitamin C is well-absorbed when we take it by mouth, the amount we absorb significantly decreases the higher the dose we take.

One source states:

Approximately 87% of a 30 mg oral dose is absorbed, 80% of a 100 mg dose is absorbed, 63 % of a 500 mg dose is absorbed, and less than 50% of a 1250 mg does is absorbed.

So, the bottom line here is the more vitamin C you take, the less you absorb. So, even if you take more vitamin C than you intend to, you'll just excrete out that excess when you go to the bathroom.

Final Words

You can feel safe taking a multivitamin along with your vitamin C supplement.

I wanted to thank you again for reaching out!

Feel free to contact us again with any more questions.