Let’s Talk Vitamin C

You’ve probably heard that vitamin C supports your immune system. This essential micronutrient seems to be everywhere! And it’s a good thing because, unlike most mammals, humans can’t synthesize vitamin C on their own.1 Also, vitamin C is water-soluble, which means the body quickly loses this essential vitamin through urine, so it’s important to make vitamin C a daily part of your diet.1

Having extremely low levels of vitamin C for prolonged periods can result in scurvy, a historical disease linked to pirates and sailors who faced long journeys at sea without fresh fruits and vegetables. While cases of scurvy in the United States are rare, a recent study reported that 31% of the US population are not meeting the daily recommended intake of vitamin C.1 Greater than 6% of the US population are severely vitamin C deficient, while low levels of vitamin C, associated with weakness and fatigue, were observed in 16% of Americans.2 As a whole, 20% of the US population showed marginally low levels of this essential micronutrient.2

How much vitamin C do I need?

The US recommended daily dietary allowance of vitamin C is 75 mg for women and 90 mg for men.3 Experts recommend an estimated 200 mg of vitamin C daily for favorable health benefits.4 Adults can take up to 2,000 mg of vitamin C per day; however, high doses of vitamin C may cause diarrhea, nausea, and stomach cramps.5 Due to the varying health needs of individuals, it’s always a good idea to work with your healthcare practitioner to ensure that you are getting the right amounts of micronutrients in your daily diet.

Where can you find this marvelous, multifaceted micronutrient?

Ready to add vitamin C to your daily regimen? Talk to your healthcare practitioner about how much would be right for you.

For other general wellness topics, please visit the Metagenics blog.


1. Granger M et al. Adv Food Nutr Res. 2018;83:281-310.
2. Schleicher RL et al. Am J Clin Nutr. 2009;90(5):1252-1263.
3. https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/. Accessed August 3, 2021.
4. Frei B et al. Crit Rev Food Sci Nutr. 2021;52(9):815-829. 
5. Hathcock JN et al. AM J Clin Nutr. 2005;81(4)736-745.
6. Ashor AW et al. Eur J Clin Nutr. 2017;71(12):1371-1380.
7. Mason SA et al. Free Radic Biol Med. 2016;93:227-238.
8. Chen S et al. Clin J Pain. 2016;32(2):179-185.
9. Carr AC et al. J Transl Med. 2017;15(1):77.
10. Dionne CE et al. Pain. 2016; 157(11):2527-2535.
11. Chin KY et al. Curr Drug Targets. 2018;19(5):439-450.
12. Ratajczak AE et al. Nutrients. 2020;12(8):2263.
13. Dixit S et al. ACS Chem Neurosci. 2015;6(4):570-581.
14. Monacelli F et al. Nutrients. 2017;9(7):670.
15. Johnston CS et al. J of Nutr. 2007;137(7):1757–1762.
16. Johnston CS et al. Nutr Metab (Lond). 2006;3(35):1743-7075.
17. Moores J. Br J Community Nurs. 2013;Suppl:S6-S11.
18. Carr AC et al. Nutrients. 2017;9:1211.
19. Shaw G et al. Am J Clin Nutr. 2017;105(1):136-143.
20. Ratajczak AE et al. Nutrients. 2020;12(8):2263.
21. Ashor AW et al. Nutr Res. 2019;61:1-12.
22. Moser MA et al. Int J Mol Sci. 2016;17(8):1328.
23. Wu JR et al. J Cardiovasc Nurs. 2019;34(1):29-35.
24. Akolkar G et al. Am J Physiol Heart Circ Physiol. 2017;313(4):H795-H809.
25. Cook JD et al. Amer J Clin Nutr. 2001;73(1):93-98.
26. Saunders AV et al. Med J Aust. 2013;199(S4):S11-S16.
27. Amr M et al. Nutr J. 2013;12:31.
28. Consoli DC et al. J of neurochem. 2021;157(3):656-665.
29. Bajpai A et al. J Clin Diagn Res. 2014;8(12):CC04-CC7.
30. Koizumi M et al. Nutr Res. 2016;36(12):1379-1391.
31. Whyand T et al. Respir Res. 2018;19(1):79.
32. Azuma A et al. Tairyoku Kagaku Japanese J of Phys Fit and Sports Med. 2019;68(2):153-157.

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