What it is
Vitamin C is a water-soluble vitamin.
What it does
Vitamin C is a coenzyme for chemical reactions involved in protein metabolism (most notably, collagen synthesis). It also functions as a general antioxidant.
The recommended intake for vitamin C is 110mg per day for men and 95mg per day for women who aren’t pregnant or lactating. Pregnancy and lactation can increase intake requirements for vitamin C.
The safe upper limit for vitamin C intake is 2000mg per day.
Likelihood of tracking completeness: Very low
Vitamin C is not a nutrient that food manufacturers are required to disclose on nutrition labels. The vast majority of food and beverage manufacturers do not voluntarily list vitamin C content on nutrition labels, so most branded products in the MacroFactor database lack information on vitamin C. So, if you’d like to accurately track your vitamin C intake, you’ll need to make a point of mostly tracking “common foods,” which come from research-grade databases that have full nutrient reporting.
For more on when you can track using branded foods versus common foods when you’re trying to accurately monitor your intake of particular nutrients, you should check out this article.
Likelihood of insufficient intake: Low
Most adults in developed countries consume adequate amounts of vitamin C.
For more on nutrients with a greater likelihood of insufficient or excessive intake, you should check out this article.
Signs of deficiency/insufficiency
Vitamin C deficiency leads to a disease called scurvy (no, scurvy is not just an adjective used by pirates). Early signs of scurvy include general fatigue and gum irritation. As the disease progresses, the symptoms are what you’d expect for poor collagen synthesis, including connective tissue disorders, skin spots resulting from broken capillaries, impaired wound healing, and bleeding gums. Advanced scurvy can be fatal.
Acerola cherries, peppers, watercress, guava, most berries, citrus fruits, kiwis, and cruciferous vegetables are all great sources of vitamin C.
If you’d like to learn more about micronutrients generally, there’s a five-part series on the MacroFactor website you might enjoy.