Vitamin C in health, disease prevention and treatment
What it found
Vitamin C is needed for collagen, immunity and iron absorption, and studies suggest it may help in some conditions, but results are mixed and more research is needed.
The evidence comes from people, animals and lab tests.
What they found
Studies in people
Heart disease studies
Studies on vitamin C and heart disease have had conflicting results. Some found no link to lower coronary artery disease risk, while others suggested a lower risk. A 2021 analysis found that genetically predicted vitamin C blood levels did not influence major heart disease, suggesting supplements may not help prevent it.
Blood pressure in diabetes
In a 6-week trial of 24 people with type 2 diabetes, 1000 mg per day of vitamin C lowered blood pressure and oxidative stress markers and increased nitric oxide. Another study in 2018 had similar results.
Cancer prevention
Vitamin C from food was linked to an 18% lower chance of developing lung cancer, but supplements did not show this benefit. A genetic analysis found no clear evidence linking vitamin C levels to several cancers.
Studies in people and animals
Collagen and scurvy
Vitamin C is needed for collagen synthesis. Severe deficiency causes scurvy, which has affected sailors and soldiers historically and still occurs in vulnerable groups. In 18 children with scurvy from processed diets, symptoms resolved within 4 to 16 weeks after 100 to 250 mg per day.
Brain and nerve effects
In mouse models, vitamin C improved cognitive activity in schizophrenia and Alzheimer's disease. In people, low vitamin C levels in plasma and cerebrospinal fluid are linked to advanced Alzheimer's, but supplements have not been shown to prevent Parkinson's disease.
Infections and immunity
Vitamin C supports immune cells and may help fight infections. In lab tests, it inhibited the growth of bacteria such as Pseudomonas aeruginosa, Staphylococcus aureus and Escherichia coli, and viruses like herpes simplex and rabies. In people, 1 g per day for 28 days increased T lymphocyte proliferation.
What the authors conclude
“However, VIC remains a necessary vitamin that should be consumed daily to maintain optimal health and prevent deficiencies that can lead to scurvy and its associated complications.”
Also in their conclusions
- They conclude that vitamin C is a necessary vitamin that should be consumed daily to maintain optimal health and prevent deficiencies that can lead to scurvy.
- They state that further studies on larger samples and over a longer period are needed to demonstrate the therapeutic potential of this nutrient.
- They advise that efforts to combat vitamin C deficiency should prioritize increasing access to fresh produce and promoting public health initiatives targeting high-risk populations.
How it was done
The authors wanted to review the importance of vitamin C in improving quality of life and preventing diseases such as chronic diseases, cardiovascular diseases and cancer, and its use in treating infections, neurodegenerative diseases and cancer.
They analysed English-language publications, mainly from the last seven years, including reviews, meta-analyses, preclinical studies, clinical trials and observational studies, searched in scientific databases using keywords such as vitamin C, cardiovascular diseases, immune system and cancer treatment.
What it can’t tell you
- Many findings come from animal or lab studies, which cannot show what happens in people.
- Some studies in people are observational and can show links but not cause and effect.
- The review notes that some studies contradict each other, so the overall picture is not clear.
Who paid
- Conflicts
- The authors declare no conflicts of interest.
- Authors work at
- Carol Davila University of Medicine and Pharmacy, Romania; National University of Science and Technology Politehnica Bucharest, Romania; Research Institute of the University of Bucharest-ICUB, Romania
The paper
- Title
- Vitamin C: A Comprehensive Review of Its Role in Health, Disease Prevention, and Therapeutic Potential
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Studies in people · animals · lab
- Summarised from
- Full text
- Cite
- Alberts A, Moldoveanu ET, Niculescu AG, Grumezescu AM (2025). Vitamin C: A Comprehensive Review of Its Role in Health, Disease Prevention, and Therapeutic Potential. Molecules (Basel, Switzerland). doi:10.3390/molecules30030748Free full textPubMed 39942850DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error