The best vitamin C supplement

Ana Sanchez

Cold and flu season is upon us and stocking up on a good vitamin C supplement is one way to keep sickness at bay. Vitamin C is best known for boosting the immune system, but it's also a powerful antioxidant with many other benefits, including fighting inflammation.

Your body doesn't produce vitamin C on its own, so if you're not getting enough vitamin C through your diet, you'll want to consider a supplement. This shopping guide will help you navigate through all the types of vitamin C available and includes a few reviews at the end. Our top pick is Viva Naturals' Vitamin C, a premium vitamin that features added bioflavonoids for increased absorption.

Considerations when choosing vitamin C supplements

Types of vitamin C

Vitamin C comes either in a pure form or bound to minerals to create an "ascorbate" form. The following are the most common types of vitamin C supplements:

Ascorbic acid: Also called L-ascorbic and L-ascorbate, ascorbic acid is vitamin C in its purest form. It's the most bioavailable form, meaning it is readily absorbed by the body through the bloodstream.

Sodium ascorbate: Pure ascorbic acid can be too acidic for some people's stomach (and cause heartburn). If this is the case, opt for ascorbic acid that is attached to a sodium molecule, which minimizes the acidity. Be aware that sodium ascorbate forms of vitamin C will raise your levels of sodium if you're watching your salt intake.

Calcium ascorbate: This form binds ascorbic acid to calcium which, like sodium ascorbate, neutralizes the acidity. Calcium ascorbate is ideal for those who have extra-sensitive stomachs, are ill, or can't tolerate other forms of vitamin C.

Other mineral ascorbates: You may see ascorbic acid bound to additional minerals in multivitamins, like magnesium, chromium, zinc, manganese, and molybdenum. When you take any mineral ascorbate form (including sodium and calcium) pay attention to how much of the mineral you're ingesting and that the amount doesn't exceed the recommended daily allowance of that mineral.


Supplement form: Vitamin C supplements generally come in three different forms: pills (tablets and capsules), chewables, and powders. While no form is better than the other, be sure to check the amount of vitamin of C per serving, which varies. Powders are the most cost-effective form, but you also have to mix them with liquid, which can be inconvenient and messy.

Dosage: Vitamin C supplements range widely in dosage from 25 milligrams (mg) to 1,500 mg per unit. Doctors recommend taking smaller doses spread throughout the day and not exceeding 2,000 mg a day.

Sustained-release capsules: Also called delayed or timed, this feature means that the capsule or tablet doesn't release all its vitamin C at once. The body can only absorb so much vitamin C at one time, and if too much is introduced to your system, the absorption rate drops by 50%. Coated pills ensure that only small amounts of vitamin C are gradually introduced to your body.


Pill forms of vitamin C range in price from five to 20 cents per unit. Powder forms cost more upfront, between $12 to $20 per pound, but yield more doses per bottle.


Q. What's the recommended dosage of vitamin C?

A. The recommended daily amount (RDA) for adults is between 60 to 90 mg. The upper limit is 2,000 mg. Because it's a water-soluble vitamin, your kidneys will flush out excess amounts. However, taking too much can result in symptoms like stomach cramps, diarrhea, nausea, and vomiting.

Q. What is the benefit of bioflavonoids added to vitamin C supplements?

A. There are claims that bioflavonoids, the nutrients found in the rinds of citrus fruits, may increase the bioavailability of vitamin C. While these claims aren't substantiated, bioflavonoids have nutritional value and certainly won't hurt.

Vitamin C supplements we recommend

Best of the best: Viva Naturals' Premium Non-GMO Vitamin C

Our take: A high-quality, potent vitamin C supplement with added bioflavonoids.

What we like: Each vegetarian capsule boasts 1,000 mg of vitamin C. Pure L-ascorbic acid. Non-GMO and third-party tested for quality. Blend of bioflavonoids for increased absorption.

What we dislike: May cause heartburn and nausea in sensitive individuals.

Best bang for your buck: NOW Foods Vitamin C Sustained Release Tablets

Our take: Bargain-priced, potent vitamin C tablets featuring delayed release.

What we like: Each tablet contains 1,000 mg of vitamin C, costing five cents. Includes rose hips for an additional source of vitamin C. Sustained release so it slowly enters your body.

What we dislike: Tablets are too large for some consumers to swallow.

Choice 3: Garden of Life's Vitamin C Capsules

Our take: Vegetarian vitamin C capsules sourced from natural raw food.

What we like: Contains no binders or fillers. Includes bioflavonoids and added probiotics and enzymes for healthy digestion. Easy to swallow.

What we dislike: High-quality formula comes at a premium price tag.

Ana Sanchez is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money. BestReviews never accepts free products from manufacturers and purchases every product it reviews with its own funds.

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