How Much Vitamin C Should You Take Per Day?

Quick Health Scoop

• Vitamin C plays a key role in supporting a healthy immune system^†
• If you eat a healthy, balanced diet with plenty of fruits and vegetables, you probably get enough Vitamin C every day. If not, consider a Vitamin C supplement
• Most adults need 65 to 90 mg of Vitamin C per day
• Taking mega-doses of Vitamin C through supplements might cause health issues

Whether it’s the dead of winter or the heat of summer, the importance of a well-functioning immune system is a critical component of staying healthy. That’s why you might turn to Vitamin C (also known as ascorbic acid), an essential nutrient and antioxidant, that supports your healthy immune system and helps neutralize damaging free radicals. And because your body can’t make Vitamin C, you need to get it from your diet and possibly supplements.^†

But you might be asking yourself, “How much Vitamin C should I take?” And, in the quest to support your healthy immune system, you might wonder just how much Vitamin C is too much? Read on to learn how you can safely put the mighty Vitamin C to work for you in just the right dose.^†

How Many MG Of Vitamin C Do You Need Per Day?

You might be surprised to learn that the recommended dietary allowance (RDA) of Vitamin C for adults is probably lower than you think. A quick reminder about what RDA is: The RDA is set by the Food and Nutrition Board of the National Academies of Sciences, which establishes principles and guidelines of adequate dietary intake. While Dietary Reference Intake (DRI) is the general term for a set of reference values used to plan and assess nutrient intakes of healthy people, the Recommended Dietary Allowance (RDA) is the average daily level of intake sufficient to meet the nutrient requirements of nearly all (97–98%) healthy individuals; often used to plan nutritionally adequate diets for individuals. 

The recommended daily amount for adult men is 90 mg/day, but goes up to 125 mg/day for smokers, as smoking increases the need for more antioxidant support. While healthy women generally need 75 mg of Vitamin C per day, the recommendation goes up for women who smoke (110 mg/day) and for pregnant or breastfeeding women (85 mg to 120 mg per day).^{2, †}

It’s important to know also that Vitamin C is a common nutrient shortfall. This means that a percentage of Americans are not reaching the recommended intake requirements of Vitamin C from diet alone – almost half.[6] For common shortfall nutrients, like Vitamin C, increasing your intake from food and/or supplements is a way to help you fill in potential nutritional gaps of these essential nutrients.

Learn More: How Much Vitamin C Should a Pregnant Woman Take?

How Much Vitamin C Is Too Much?

A Tolerable Upper Intake Level (UL) was set for Vitamin C at 2,000 mg per day for most adults to prevent healthy adults from experiencing the unpleasant side effects noted below. However, people with certain health issues (such as chronic liver or kidney conditions, gout, or a history of calcium-oxalate kidney stones) should limit their intake to a maximum of 1,000 mg a day.²

What Are Possible Side Effects of Too Much Vitamin C?

If you eat too many foods with Vitamin C, it probably won’t be harmful. But if you take mega-doses of Vitamin C through supplements, they might cause the following health issues:¹

• Abdominal cramps
• Diarrhea
• Headache
• Heartburn
• Insomnia
• Nausea
• Vomiting

How Much Vitamin C Is In An Orange?

While you might typically turn to oranges as your go-to Vitamin C food source, you can get this immune-supporting nutrient in other fruits and vegetables, too. For example, take a look at these Vitamin C-rich food sources:^{3, †}

• Sweet Yellow Peppers (1/2 cup): 137 mg
• Guava (1 medium): 126 mg
• Kale (1 cup, raw): 80 mg
• Kiwi (1 medium): 71 mg
• Broccoli (1/2 cup, cooked): 51 mg
• Brussels Sprouts (1/2 cup, cooked): 49 mg
• Lemons (1 medium): 83 mg
• Papaya (1 cup): 87 mg
• Strawberries (1 cup): 89 mg
• Orange (1 medium): 70 mg

Tip: Did you know that excessive heat can destroy Vitamin C in food? To get as much Vitamin C from these foods as possible, eat them raw or lightly cooked. Try cooking them for shorter periods of time, preferably through steaming or microwaving, which limits the loss of nutrients in the cooking process.⁴

Realistically, if you eat a healthy, balanced diet with plenty of fruits and vegetables, you probably get enough Vitamin C in your daily diet. However, if you don’t consume these types of foods every day, a Vitamin C supplement can be helpful.

Learn More: Vitamin D Immune System Benefits

The Bottom Line

Vitamin C helps support your healthy immune system and helps to neutralize damaging free radicals as an antioxidant. If you eat a nutritious, balanced diet, you should get what you need every day. And taking mega-doses of Vitamin C can actually cause some negative side effects. But if you don’t regularly eat Vitamin C-rich foods, consider taking a Vitamin C supplement to close the nutritional gap.^†

† 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.

References

1. Mayo Clinic. “Is it possible to take too much vitamin C?” March 18, 2020. Accessed on: October 2, 2020. https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/vitamin-c/faq-20058030#:~:text=For%20adults%2C%20the%20recommended%20daily,Nausea 

2. Harvard Health Publishing. “By the way, doctor: What's the right amount of vitamin C for me?” April 3, 2019. Accessed on: October 7, 2020. https://www.health.harvard.edu/staying-healthy/whats-the-right-amount-of-vitamin-c-for-me 

3. US Department of Agriculture. FoodData Central. Accessed January 26, 2023. https://fdc.nal.usda.gov/

4. Academy of Nutrition and Dietetics. “How Vitamin C Supports a Healthy Immune System” March 22, 2019. Accessed on: October 6, 2020. 

5. Linus Pauling Institute. “Vitamin C.” December 2018. Accessed on: October 6, 2020. https://lpi.oregonstate.edu/mic/vitamins/vitamin-C

6. Reider, C.A.; Chung, R.-Y.; Devarshi, P.P.; Grant, R.W.; Hazels Mitmesser, S. “Inadequacy of Immune Health Nutrients: Intakes in US Adults, the 2005–2016 NHANES.” Nutrients 2020, 12, 1735.