What will happen to my body if I drink vitamin C every day?

October 27, 2025 •

4 min read

According to the National Institutes of Health, vitamin C is a vital nutrient that the body cannot produce on its own and must obtain from the diet. So, what will happen to my body if I drink vitamin C every day, and how does this daily habit impact overall health, especially when consuming more than the required amount?

Quick Summary

Daily vitamin C intake supports immune function, collagen synthesis, and iron absorption. As a water-soluble vitamin, excess amounts are typically excreted, but high doses can cause gastrointestinal issues and increase the risk of kidney stones. Optimal levels are best obtained through a balanced diet.

Key Points

Supports Vital Bodily Functions: Daily vitamin C intake is crucial for collagen synthesis, wound healing, and maintaining healthy skin, bones, and blood vessels.
Acts as a Potent Antioxidant: The vitamin protects cells from oxidative stress caused by free radicals, which can contribute to chronic diseases and aging.
Enhances Iron Absorption: It significantly improves the absorption of iron, especially non-heme iron from plant sources, which is beneficial for preventing iron deficiency.
Offers Limited Cold Protection: Regular, preventive intake may slightly shorten cold duration or lessen symptoms for some, but it will not prevent you from getting a cold.
Presents Risks at High Doses: Consuming significantly more than recommended daily amounts can cause unpleasant side effects, including digestive issues like diarrhea, nausea, and stomach cramps.
Increases Kidney Stone Risk: Excessive intake, particularly from supplements, raises the risk of kidney stone formation due to increased oxalate excretion.
Best Sourced from Food: The optimal way to get enough vitamin C is through a healthy, balanced diet rich in fruits and vegetables, which provide a broader range of nutrients.

The Importance of Daily Vitamin C Intake

Consuming a sufficient, daily amount of vitamin C is essential for numerous bodily functions. Known also as ascorbic acid, this water-soluble vitamin is a powerful antioxidant that helps protect your cells from the damage caused by free radicals. Free radicals are unstable molecules that contribute to aging and the development of chronic conditions like heart disease and cancer. By neutralizing these molecules, vitamin C helps maintain overall cellular health.

One of vitamin C's most critical roles is its involvement in the production of collagen, the main structural protein found in connective tissues. This protein is vital for maintaining healthy skin, strong bones, and healthy cartilage, tendons, and ligaments. Collagen is also crucial for healing wounds and forming scar tissue. This means a consistent daily intake can support skin elasticity and aid the body's repair processes.

Beyond its role in structural integrity, vitamin C significantly enhances the absorption of non-heme iron, the type of iron found in plant-based foods. This is particularly important for people who follow a plant-based diet or those with iron deficiency anemia. A daily dose of vitamin C, whether from food or a supplement, can help ensure your body efficiently absorbs this vital mineral.

Vitamin C and the Common Cold

For many years, vitamin C has been a popular go-to remedy for fighting the common cold. However, research has largely debated the idea that it can prevent you from getting sick. While taking a vitamin C supplement regularly may not significantly reduce your risk of catching a cold, some evidence suggests it might slightly shorten the duration or lessen the severity of your symptoms. It's a key component of the immune system, helping white blood cells function effectively and protecting them from damage, but it's not a definitive cure or preventative.

Potential Risks of Excessive Daily Intake

Because vitamin C is water-soluble, your body cannot store large excess amounts; any unabsorbed vitamin C is typically excreted through urine. This makes overdosing much less likely than with fat-soluble vitamins. However, consuming high doses—especially from supplements—can still lead to unpleasant side effects. Consuming amounts exceeding typical daily needs can trigger adverse reactions.

Common side effects of excessive intake, often from supplement use, include:

Gastrointestinal Distress: Diarrhea, nausea, stomach cramps, bloating, and heartburn are common complaints as the unabsorbed vitamin C ferments in the gut.
Kidney Stones: For some individuals, particularly those with a history of kidney issues, high amounts of vitamin C can increase the risk of kidney stone formation. Vitamin C increases the amount of oxalate in the urine, which can contribute to stone formation.
Increased Iron Absorption: While beneficial for iron-deficient individuals, those with hereditary hemochromatosis (a condition of iron overload) can experience dangerous tissue damage from excessive iron absorption triggered by high vitamin C intake.
Interference with Medications: High doses of vitamin C can potentially interfere with certain medications, including anticoagulants like warfarin and some chemotherapy drugs.

Sourcing Your Daily Dose: Food vs. Supplements

While supplements are a convenient way to boost intake, obtaining vitamin C from whole foods is generally considered the best approach. Fruits and vegetables are not only packed with vitamin C but also offer a range of other beneficial vitamins, minerals, antioxidants, and fiber. Most people who eat a varied and balanced diet will have no trouble meeting their daily needs.

Here are some excellent food sources of vitamin C:

Citrus Fruits: Oranges, grapefruits, lemons.
Berries: Strawberries, blueberries, raspberries.
Cruciferous Vegetables: Broccoli, Brussels sprouts, kale.
Peppers: Bell peppers (especially red).
Other Fruits: Kiwi fruit, cantaloupe, tomatoes.

Comparing Adequate and Excessive Vitamin C Intake


Aspect	Adequate Daily Intake (meeting recommended needs)	Excessive Daily Intake (consuming significantly more than recommended)
Immune System	Supports normal immune function and white blood cell activity.	Does not provide significant extra immunity beyond adequate levels.
Antioxidant Effect	Protects cells from oxidative damage caused by free radicals.	Can potentially act as a pro-oxidant at very high concentrations, though effects in humans are unclear.
Collagen Production	Essential for synthesis, supporting skin, bones, and wound healing.	No additional benefit; body simply uses what is needed.
Iron Absorption	Enhances absorption of plant-based iron.	Can cause excessive iron buildup in those with hemochromatosis.
Digestive Impact	Well-tolerated with no significant gastrointestinal effects.	Can lead to diarrhea, nausea, cramps, and heartburn.
Kidney Health	No increased risk of kidney stones in healthy individuals with typical intake.	Increased risk of kidney stone formation, particularly in susceptible people, with high intake.

Conclusion

Drinking vitamin C every day, in amounts that meet dietary needs, is a healthy practice that provides a wealth of benefits, from supporting your immune system and boosting collagen production to enhancing iron absorption. However, consistently consuming significantly more than the recommended daily amount offers no additional benefits and carries a risk of unpleasant side effects, particularly for the digestive and urinary systems. For most healthy individuals, the best way to maintain optimal vitamin C levels is by consuming a balanced diet rich in fresh fruits and vegetables. While supplements can be a convenient tool, they should be used judiciously and in consultation with a healthcare provider to avoid potential complications, especially in cases of pre-existing health conditions.

Here is a link to the NIH Office of Dietary Supplements for more information.

Frequently Asked Questions

For most adults, aiming to meet the recommended dietary allowance (RDA) is appropriate. This can often be achieved through a balanced diet rich in fruits and vegetables.

Yes, for most people, a healthy and varied diet provides all the vitamin C needed. Excellent sources include citrus fruits, bell peppers, strawberries, broccoli, and kale.

The most common early signs of excessive vitamin C intake are digestive issues such as nausea, diarrhea, stomach cramps, and heartburn.

Yes, there is a Tolerable Upper Intake Level (UL) for adults. Consuming more than this amount regularly, especially from supplements, is not recommended and increases the risk of side effects.

No, taking vitamin C every day does not prevent you from catching a cold. However, regular intake might slightly reduce the duration or severity of cold symptoms in some people.

Yes, in certain individuals, particularly those predisposed to them, high intake of vitamin C can increase the risk of kidney stone formation.

No, getting vitamin C from food is generally preferable. Whole foods provide a mix of other beneficial nutrients, such as fiber and additional antioxidants, that supplements lack.