Vitamin C’s association with scurvy is so historically dominant that its broader biology tends to get overlooked. A 2025 comprehensive review in Molecules lays out just how much vitamin C actually does in the body — as an antioxidant, an enzyme cofactor, and a nutrient whose deficiency is quietly more common in specific populations than most people assume, even in wealthy countries.
What Vitamin C Actually Does
Ascorbic acid is a cofactor for enzymes involved in collagen biosynthesis, hormone synthesis, immune function, iron absorption, and carnitine metabolism (carnitine transports fatty acids into mitochondria for energy production). It’s also a genuine antioxidant — it donates electrons to neutralize free radicals and reactive oxygen species, protecting lipids, proteins, and DNA from oxidative damage, and even helps regenerate vitamin E’s antioxidant capacity once it’s been used up.
The Collagen Connection
Vitamin C is an essential cofactor for prolyl and lysyl hydroxylase — the enzymes that cross-link collagen molecules into their stable triple-helix structure. Without adequate vitamin C, this cross-linking fails, which is the direct biochemical cause of scurvy’s connective-tissue symptoms: gum disease, poor wound healing, and fragile blood vessels. Vitamin C also increases collagen gene expression itself, meaning it doesn’t just help assemble collagen — it helps produce more of it.
Who’s Actually at Risk of Deficiency
Since the body can’t synthesize vitamin C on its own, intake depends entirely on diet. The review highlights specific risk factors: geography (countries with limited access to fresh produce, like Finland and Russia, show higher deficiency prevalence), socioeconomic disadvantage, smoking and alcohol use (both accelerate vitamin C depletion via increased oxidative stress), and chronic conditions including obesity, cardiovascular disease, diabetes, and cancer. A 2023 study found scurvy occurring in pediatric populations on processed diets lacking fresh produce — a reminder that scurvy isn’t purely historical.
Beyond Deficiency Prevention
The review covers vitamin C’s studied roles in cardiovascular disease, cancer, infections, and neurodegenerative disease — with an important caveat: the evidence quality varies substantially by area, and some studies contradict each other. One area of active research interest: at high (pharmacological) concentrations, vitamin C can act as a pro-oxidant rather than antioxidant, a property being studied specifically for its potential in cancer treatment, including as a way to potentiate chemotherapy drugs like gemcitabine.
How Much Is Enough
Adequate daily intake is generally around 90 mg for men and 75 mg for women, though pregnant and breastfeeding women need more, and smokers need an additional 35 mg/day due to increased vitamin C turnover from smoking-related oxidative stress. Consistent intake of around 200 mg/day through diet and supplements is described as important for sustaining adequate levels — notably higher than the minimum needed just to prevent scurvy.
The Bottom Line
Vitamin C’s role goes well beyond scurvy prevention — it’s genuinely central to collagen production, iron absorption, and the body’s antioxidant defenses, and deficiency risk is real and measurable in specific modern populations, not just a historical curiosity. The review’s own framing is balanced: vitamin C “remains a necessary vitamin that should be consumed daily,” while its broader therapeutic potential in areas like cancer and cardiovascular disease still needs larger, longer studies to confirm.
References
[1] Alberts, A.; Moldoveanu, E.-T.; Niculescu, A.-G.; Grumezescu, A.M. “Vitamin C: A Comprehensive Review of Its Role in Health, Disease Prevention, and Therapeutic Potential.” Molecules 2025, 30, 748. https://doi.org/10.3390/molecules30030748 (open access)
