Vitamin C Deficiency and Scurvy: Early Warning Signs and Who Is at Risk

Vitamin C deficiency can develop quietly over weeks or months, and its most severe form, scurvy, is entirely preventable with adequate dietary intake. Understanding who is vulnerable and what symptoms to watch for is the first step toward protecting your health.

What Vitamin C Does in the Body

According to the NIH Office of Dietary Supplements (ODS), vitamin C is required for the biosynthesis of collagen, an essential component of connective tissue that plays a vital role in wound healing. It is also needed to make L-carnitine and certain neurotransmitters, and it is involved in protein metabolism. Beyond those structural roles, vitamin C acts as an important physiological antioxidant that limits damage from free radicals and helps regenerate other antioxidants, including alpha-tocopherol (vitamin E). The evidence for these core physiological functions is rated strong by the NIH ODS.

Vitamin C also supports immune function and enhances the absorption of nonheme, or plant-based, iron. The NIH ODS rates the evidence for both of these roles as strong as well.

How Much Do You Need?

The NIH ODS reports the following Recommended Dietary Allowances for adults aged 19 and older: 90 mg per day for men and 75 mg per day for women. The Tolerable Upper Intake Level for healthy adults is 2,000 mg per day. Intakes above that upper limit raise the risk of gastrointestinal effects such as diarrhea and cramps. Note that lower upper limits apply to children and adolescents, and the upper limit does not apply to people receiving vitamin C for medical treatment under a physician's care.

Smokers require an additional 35 mg per day above the standard recommendation because smoking increases oxidative stress and depletes vitamin C more rapidly.

Early Warning Signs of Deficiency

Because collagen synthesis depends directly on vitamin C, the earliest symptoms tend to involve connective tissue. Deficiency typically develops after several weeks of very low intake. Early signs can include:

• Fatigue and general weakness, often among the first symptoms to appear
• Irritability or low mood
• Small, pinpoint bleeding under the skin (petechiae) around hair follicles
• Dry, rough, or bumpy skin texture
• Gums that bleed easily, especially when brushing teeth
• Slow healing of minor cuts or bruises
• Joint pain or swelling

If intake remains very low for months, the condition can progress to scurvy, which involves more pronounced bleeding of the gums, loosening of teeth, swollen and painful joints, and severe fatigue. Scurvy is a medical emergency that requires clinical evaluation and treatment. If you suspect you or someone you care for may have scurvy, contact a healthcare provider promptly.

Who Is Most at Risk?

Certain groups face a meaningfully higher risk of inadequate vitamin C intake or absorption.

People Who Smoke

Smokers have lower blood levels of vitamin C than nonsmokers at the same intake level, which is why the NIH ODS recommends an additional 35 mg per day for this group. Secondhand smoke exposure may also lower levels, though data are less definitive.

People With Limited Food Access or Poor Dietary Variety

Vitamin C is found almost exclusively in fruits and vegetables. People who rely heavily on processed foods, have limited access to fresh produce, or follow very restrictive diets are at elevated risk. This includes some older adults in institutional care settings and individuals experiencing food insecurity.

People With Certain Medical Conditions

Conditions that impair nutrient absorption, such as inflammatory bowel disease or some gastrointestinal surgeries, can reduce how much vitamin C the body retains. People on dialysis for kidney disease also lose vitamin C during treatment sessions. Anyone managing a chronic condition should ask their clinician whether routine monitoring of vitamin C status is appropriate.

Infants Fed Exclusively Boiled or Evaporated Milk

Heat destroys vitamin C. Infants who receive only boiled or evaporated cow's milk rather than breast milk or properly formulated infant formula are at risk. Breast milk from a well-nourished mother provides adequate vitamin C.

People With Alcohol Use Disorder

Heavy alcohol use is associated with poor dietary intake overall and with lower absorption of several nutrients, including vitamin C.

Food Sources First

Most people can meet their daily needs through food. Rich sources include citrus fruits, kiwi, strawberries, bell peppers, broccoli, Brussels sprouts, and tomatoes. Cooking reduces vitamin C content, so eating some raw fruits and vegetables each day is a practical strategy.

Should You Take a Supplement?

For healthy people who eat a varied diet, a supplement is generally not necessary. For those who struggle to meet needs through food, a standard supplement providing up to the daily recommended amount is considered safe. The NIH ODS states that for healthy people, vitamin C from food and supplements is safe up to the Tolerable Upper Intake Level of 2,000 mg per day for adults.

As with any supplement, consult a clinician or pharmacist before starting one, especially if you take prescription medications. Two interactions are worth noting. First, it is uncertain whether high-dose vitamin C and other antioxidants protect or harm tumor cells or alter the effectiveness of chemotherapy or radiation therapy. Anyone undergoing cancer treatment should consult their oncologist before taking vitamin C supplements, especially in high doses. Second, vitamin C combined with other antioxidants may reduce the rise in HDL cholesterol produced by combination niacin and simvastatin therapy. Clinicians should monitor lipid levels in people taking both statins and antioxidant supplements.

Vitamin C supplements are not intended to diagnose, treat, cure, or prevent any disease, and these statements have not been evaluated by the FDA.

What the Research Does and Does Not Show

It is worth being clear about what the science supports. The NIH ODS rates the evidence as insufficient that taking vitamin C supplements prevents the common cold in the general population, reduces cancer risk, or prevents cardiovascular disease. Evidence that regular supplementation modestly shortens cold duration is rated moderate. Evidence that vitamin C reduces the risk of age-related cataract or macular degeneration is rated limited. These distinctions matter when weighing whether supplementation makes sense for you personally, and that conversation is best had with a healthcare provider who knows your full health picture.

When to See a Doctor

If you notice unexplained bruising, bleeding gums, wounds that are slow to heal, or persistent fatigue, speak with a clinician. A blood test can assess your vitamin C status. Self-diagnosing deficiency or starting high-dose supplementation without guidance is not recommended, particularly if you have any ongoing health condition or take medication.