test-Benefits of Vitamin C and The Best Vitamin C Supplements to Try
Immune Health
Benefits of Vitamin C and The Best Vitamin C Supplements to Try
Lindsey Toth, MS, RD • March 8, 2024

Vitamin C and its Benefits

Vitamin C is one of the most widely recognized nutrients. When most people think of vitamin C, their thoughts immediately jump to immune support. That’s completely expected, considering vitamin C is essential for supporting the body’s natural defense system, but it does so much more!

Vitamin C acts as a potent antioxidant that promotes cardiovascular health and supports the formation of collagen and L-carnitine as well as certain neurotransmitters.1 Vitamin C is also involved in protein metabolism, and it may help boost absorption of nonheme iron.1

Guide to Vitamin C by Swanson Health

Vitamin C Benefits

  • Vitamin C as an Antioxidant: Vitamin C provides important antioxidant support, helping protect cells from oxidative stress and the effects of free radicals, and it may also help regenerate other antioxidants within the body.1
  • Vitamin C for Heart Health: Research suggests that high intakes of foods rich in vitamin C may help support heart health. The cardiovascular benefits of vitamin C may be linked to its role as an antioxidant.1
  • Vitamin C Benefits for Weight Loss: People with adequate levels of vitamin C oxidize 30% more fat during moderate exercise than those with low vitamin C levels.2 And there is some correlation between vitamin C levels and body mass.2 Some researchers believe that low levels of vitamin C may cause us to be more resistant to losing fat.2
  • Benefits of Vitamin C for Skin: Higher intakes of vitamin C may be associated with healthy aging benefits, including reduced wrinkle formation and reduced dryness.3 These benefits may be due, in part, to the role of vitamin C in healthy collagen synthesis.1 You may also gain skin benefits from vitamin C serums or topical vitamin C skin creams like Swanson Premium Vitamin C Cream.
  • Vitamin C and L-Carnitine: L-Carnitine is an amino acid that plays a role in energy production. Our bodies produce it naturally, but low vitamin C levels have been linked to lower production of this important amino acid.4
  • Vitamin C and Neurotransmitters: Vitamin C is required for your body to carry out the enzymatic reaction that synthesizes the neurotransmitter norepinephrine from dopamine, and low vitamin C levels may increase vulnerability to free radicals and the effects of oxidative damage.5
  • Vitamin C and Protein Metabolism: Vitamin C plays a role in breaking down proteins in the body.1
  • Vitamin C Benefits for Men: Vitamin C is a popular supplement for men due to many of the benefits mentioned above, including skin benefits, heart health, protein metabolism and antioxidant support, but one study suggests vitamin C may positively impact sexual health as well.6

Which Type of Vitamin C is Best?

Given the many benefits of vitamin C, it isn’t surprising that vitamin C supplements are popular. But if you’ve compared vitamin C supplements, you've probably noticed that there are several different forms of vitamin C supplements out there, and you may wonder which form of vitamin C is best. Choosing the best nutritional supplements often comes down to bioavailability­, which is how much of the nutrient you ingest versus how much of it your body actually absorbs. So, which type of vitamin C is absorbed best?

The Types of Vitamin C

The form of vitamin C most frequently used in supplements is ascorbic acid, which has a bioavailability that is equivalent to the vitamin C that naturally occurs in foods like orange juice and broccoli.1

Other types of vitamin C include:

Some studies have shown minor differences in absorption rates between the various types of vitamin C, but the body of research surrounding vitamin C supplementation reflects high absorption no matter which form you choose.1 These findings, paired with the low cost of ascorbic acid, has led researchers to conclude that ascorbic acid is the preferred type of vitamin C supplement.1 But keep in mind that if you opt for mineral ascorbates, you may get more than just vitamin C. Always check product labels to see how much vitamin C and other minerals are in each dose so you can factor that into your overall supplementation routine.

Synthetic vs. Natural Ascorbic Acid

Ascorbic acid occurs naturally in many fruits and vegetables, like amla fruit and oranges, so you can get your daily vitamin C intake from foods too. But if you have trouble meeting your daily intake requirements of vitamin C from food alone, ascorbic acid supplements can help you fill that gap. There are no bioavailability differences between the ascorbic acid in your morning glass of orange juice and synthetic ascorbic acid in vitamin C supplements. They are chemically identical.1,7

So, whether you get your vitamin C from red bell peppers (surprisingly high in vitamin C!) or a supplement, you’re set. But, remember that foods high in vitamin C often contain other healthy nutrients as well and supplements are intended to be taken in addition to a well-balanced diet. Here are some healthy foods that are high in vitamin C.

Foods High in Vitamin C1

  • Red peppers (95 mg per 1/2 cup)
  • Orange juice (93 mg per 3/4 cup)
  • Oranges (70 mg in one medium orange)
  • Grapefruit juice (70 mg per 3/4 cup)
  • Kiwifruit (64 mg in one medium kiwi)
  • Green peppers (60 mg in 1/2 cup)
  • Broccoli (51 mg per 1/2 cup of cooked broccoli)
  • Strawberries (49 mg per 1/2 cup)
  • Brussels sprouts (48 mg per 1/2 cup)
  • Many other fruits and vegetables

Vitamin C Dosage: How Much Vitamin C Should I Take?

The amount of vitamin C you take as a supplement will depend on how much you already get from your diet. The minimum recommended daily intake of vitamin C for healthy adults is between 65 mg and 90 mg per day, and smokers need 35 mg more per day than nonsmokers. Here are the recommended dietary allowances (RDAs) of vitamin C for each age group from the National Institutes of Health (NIH) Office of Dietary Supplements.

Recommended Dietary Allowances (RDAs) for Vitamin C1

  • 0-6 months (40 mg)
  • 7-12 months (50 mg)
  • 1-3 years (15 mg)
  • 4-8 years (25 mg)
  • 9-13 years (45 mg)
  • 14-18 years (75 mg for males, 65 mg for females)
  • 19+ (90 mg for males, 75 mg for females)
  • Pregnant females between 14-18 (80 mg)
  • Nursing females between 14-18 (115 mg)
  • Pregnant females 19+ (85 mg)
  • Nursing females 19+ (120 mg)
  • Smokers (add 35 mg to above dosages)

Very High Doses of Vitamin C

You might think that taking high doses of vitamin C would mean you absorb more of it, but that isn’t necessarily the case. The body carefully controls the amount of ascorbic acid circulating in your system throughout the day, excreting any excess once you meet your body’s needs. Ingesting extremely high doses of more than 1,000 mg will not equate to more bioavailable ascorbic acid in the body.

There are exceptions, however. At the direction of a doctor, smokers and those regularly exposed to secondhand smoke, people with a severely limited diet, and individuals with health conditions that inhibit absorption of vitamin C may need increased supplementation. In those cases, liposomal vitamin C may help.

Liposomal Vitamin C

For those who need very high doses of vitamin C, liposomal vitamin C may be an option. Liposomes are tiny microscopic “bubbles” formed by phospholipids that act as carriers to deliver active agents right into cells and tissues. This is meant to provide optimal bioavailability for those who need very high doses.

Top Vitamin C Supplements

Vitamin C supplements are available in many forms, from vitamin C tablets or pills to vitamin C powders, liquid vitamin C supplements or liposomal vitamin C. Here are some vitamin C supplement options from Swanson Health.

Swanson Premium Vitamin C with Rose Hips
A high-potency source of vitamin C with rose hips. Rose hips have bioflavonoids that promote the vitamin's absorption and enhance its antioxidant potency. Each capsule supplies 1,000 mg of vitamin C with 15 mg of rose hips extract.

Swanson Ultra Ultimate Vitamin C Formula
Swanson Ultra® Ultimate Vitamin C Formula is guaranteed to deliver reliable vitamin C nourishment. With 500 mg of ascorbic acid per capsule from a proprietary buffered complex that includes zinc ascorbate and chromium ascorbate, Ultimate Vitamin C Formula makes it easy to take without stomach upset.

Swanson Premium Super Stress Vitamin B-Complex with Vitamin C
This vitamin C combination supplement is specifically formulated to replenish the nutrients that are most in demand during high-stress times. Each capsule combines a generous supply of B-complex vitamins with the powerful antioxidant protection of high-potency vitamin C.

Swanson Premium 100% Pure Vitamin C Powder
Our 100% Pure Vitamin C Powder is the perfect way to get this essential vitamin for those who have trouble swallowing pills or simply enjoy the convenience of mixing supplements into beverages and smoothies. This water-soluble vitamin dissolves easily, letting you turn almost any beverage into a vitamin-C powerhouse.

Supplementing vitamin C doesn’t have to be confusing. Fortunately, vitamin C is one of the most straightforward nutrients with plenty of options for getting your daily dose.

You be well, now.


Lindsey Bristol, Swanson Health Products

About Lindsey Toth, MS, RD

Lindsey is a nationally recognized registered dietitian and nutritionist with a soft spot for pie. She empowers people to take charge of their health by finding the balance between the pleasure and nourishment in food. Her philosophy is that you should take care of your body because it’s the only permanent home you have. It’s what inspired her to pursue a career in nutrition.

*These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.


1. Vitamin C Fact Sheet. National Institutes of Health. Read source

2. Strategies for healthy weight loss. National Library of Medicine. Read source

3. Why is Topical Vitamin C Important for Skin Health?. Harvard Health Publishing. Read source

4. L-Carnitine. Oregon State University. Read source

5. Cognitive Function In-Depth. Oregon State University. Read source

6. High-dose ascorbic acid. Science Direct. Read source

7. The Bioavailability of Different Forms of Vitamin C. Oregon State University. Read source