Vitamin C and zinc together are one of the most common pairings on the supplement shelf, and for good reason: both nutrients play a part in normal immune function, but they do different jobs. Vitamin C is a water-soluble antioxidant that immune cells collect in high amounts. Zinc is a mineral that hundreds of enzymes depend on, including those that help immune cells develop. For most healthy adults, taking them together is safe. Here is what each one does, how much you need and how to combine them sensibly.
Key takeaways
- Vitamin C and zinc support normal immune function in different ways, so they complement rather than duplicate each other.
- Most adults need 75 to 90 mg of vitamin C and 8 to 11 mg of zinc a day.
- The upper limits for adults are 2,000 mg of vitamin C and 40 mg of zinc a day from all sources.
- There is no known harmful interaction between vitamin C and zinc, so they can be taken together.
What does vitamin C do in the body?
Vitamin C, also called ascorbic acid, is a vitamin your body cannot make, so it has to come from food or supplements. It dissolves in water, and the body keeps only a modest reserve, so a steady daily intake matters. According to the NIH Office of Dietary Supplements, vitamin C:
- Acts as an antioxidant. It helps protect cells from everyday oxidative stress and helps recycle vitamin E.
- Supports normal immune function. White blood cells collect vitamin C at levels many times higher than in the blood, and a 2017 review describes its role in several types of immune cells and in the skin barrier.
- Helps make collagen. Collagen is the protein that gives structure to skin, blood vessels, tendons and the lining of the gut.
- Helps you absorb iron from plants. Vitamin C improves the uptake of the type of iron found in beans, lentils and leafy greens.
What does zinc do in the body?
Zinc is a trace mineral, needed in small amounts but involved almost everywhere. It helps hundreds of enzymes do their work. For the immune system, zinc matters because immune cells need it to develop and to signal properly. A 2017 review called zinc a "gatekeeper" of immune function for this reason. Zinc also helps the body build proteins and DNA, supports normal skin renewal, and plays a part in taste and smell.
Like vitamin C, zinc has no special storage system in the body, which is why a daily intake matters. For a deeper look at zinc forms and food sources, see our guide to zinc explained.
Vitamin C vs. zinc at a glance
| Vitamin C | Zinc | |
|---|---|---|
| Type | Water-soluble vitamin | Trace mineral |
| Main jobs | Antioxidant, collagen, iron uptake, immune cells | Enzymes, immune cell development, proteins and DNA |
| Adult daily need | 75 to 90 mg (smokers need 35 mg more) | 8 to 11 mg |
| Adult upper limit | 2,000 mg a day | 40 mg a day |
| Top food sources | Peppers, citrus, kiwi, broccoli, strawberries | Oysters, beef, crab, pumpkin seeds, beans |
| Too much can cause | Diarrhea, nausea, stomach cramps | Nausea; low copper with long-term high intake |
Most adults need 75 to 90 mg of vitamin C and 8 to 11 mg of zinc a day. The upper limits for adults are 2,000 mg of vitamin C and 40 mg of zinc a day from all sources.
Should you take vitamin C and zinc together?
There is no known harmful interaction between vitamin C and zinc, so they can be taken together. Vitamin C and zinc support normal immune function in different ways, so they complement rather than duplicate each other. That is why so many formulas pair them.
A few practical points help:
- Follow the label's timing. Some zinc products are best with food, others before a meal. Use the directions on the product you take.
- Watch other minerals. High doses of zinc can compete with copper for absorption over time, which is why the upper limit is set at 40 mg.
- Space zinc from certain medicines. The NIH notes zinc can reduce the absorption of some antibiotics (quinolones and tetracyclines) and penicillamine. Ask your pharmacist how far apart to take them.
- Skip zinc nasal sprays. The NIH warns that intranasal zinc has been linked to a loss of the sense of smell.
Is more vitamin C better?
Not really. Your body absorbs most of the vitamin C you take at everyday amounts, but absorption drops sharply at high single doses. The NIH notes that at intakes above 1 gram a day, less than half is absorbed, and the rest leaves the body. Very high intakes can also upset the stomach. Adequate, steady intake is the goal, not megadosing.
The same thinking applies to zinc. Taking more than 40 mg a day for long periods can lower copper levels and, in turn, affect immune function, which is the opposite of what people want.
What does research say about vitamin C, zinc and colds?
This is the question most people have, so it is worth being precise. A 2013 Cochrane review of vitamin C found that regular supplements did not reduce how often people in the general population caught colds, though colds were slightly shorter in people taking vitamin C every day. Research on zinc has mostly looked at lozenges and syrups taken at the first sign of symptoms, with mixed results. Both bodies of research use specific forms and amounts, and they describe study findings, not what any one supplement will do for you.
The clearer message from the research is about adequacy: people who fall short on either nutrient have less to work with. Food first, then a sensible supplement to fill gaps, is the approach most experts support.
How to get vitamin C and zinc from food
Many people can meet their needs through food. Good everyday choices, with approximate amounts from the NIH food tables:
- Red bell pepper, half a cup raw: about 95 mg of vitamin C
- Orange, one medium: about 70 mg of vitamin C
- Kiwifruit, one medium: about 64 mg of vitamin C
- Broccoli, half a cup cooked: about 51 mg of vitamin C
- Beef, 3 ounces cooked: about 4 mg of zinc
- Pumpkin seeds, 1 ounce: about 2 mg of zinc
- Chickpeas or lentils, half a cup cooked: about 1.3 mg of zinc
Vitamin C is sensitive to heat, so raw or lightly cooked fruit and vegetables keep more of it. Zinc from plant foods is absorbed less well because of natural compounds called phytates, so people who eat mostly plants may need more.
Where Immune+ fits
If you want vitamin C and zinc in a broader daily formula, Immune+ includes both. Each 2-capsule serving of Immune+ provides 180 mg of vitamin C (as ascorbic acid) and 16 mg of zinc (as zinc oxide). Against the daily values, that is 200% for vitamin C and 146% for zinc, and well below both upper limits. The formula adds European elderberry extract, vitamins E and B6, echinacea, garlic, turmeric, L-glutamine and Lactobacillus acidophilus.
Immune+ supports a healthy immune system and helps maintain antioxidant defenses.* The suggested use is two veggie capsules once a day, 20 to 30 minutes before a meal with an 8 fl oz glass of water. Every amount is on the label, with no proprietary blend, and every batch is third-party tested by an outside lab for purity and potency. Read more on our Our Standards page or browse our immune support collection.
The Immune+ label also advises: Pregnant or nursing mothers, children under the age of 18, and individuals with a known medical condition should consult a physician before using this or any dietary supplement. Do not exceed recommended dose.
Frequently asked questions about vitamin C and zinc
Can I take vitamin C and zinc at the same time?
Yes. There is no known harmful interaction between them, and many formulas combine the two. Follow the timing on your product's label and keep your total from all sources under the upper limits.
How much vitamin C and zinc should I take a day?
Most adults need 75 to 90 mg of vitamin C and 8 to 11 mg of zinc a day. The adult upper limits are 2,000 mg of vitamin C and 40 mg of zinc from food and supplements combined.
What is the difference between vitamin C and zinc?
Vitamin C is a water-soluble vitamin and antioxidant that also helps make collagen and absorb plant iron. Zinc is a trace mineral that hundreds of enzymes need, including those that help immune cells develop.
Can you take too much zinc?
Yes. Long-term intake above 40 mg a day can lower copper levels and cause other problems. Add up the zinc in every supplement you take, including multivitamins.
How much vitamin C and zinc is in Immune+?
Each 2-capsule serving of Immune+ has 180 mg of vitamin C and 16 mg of zinc. The suggested use is two veggie capsules once a day, 20 to 30 minutes before a meal.
Related reading from our Wellness Hub
- Zinc Explained: What It Does, Food Sources and Where Immune+ Fits
- Elderberry vs. Echinacea: How Two Immune Botanicals Differ
- Does Sleep Affect Your Immune System? What the Research Shows
Sources
- NIH Office of Dietary Supplements - Vitamin C: Fact Sheet for Health Professionals
- NIH Office of Dietary Supplements - Zinc: Fact Sheet for Health Professionals
- Carr AC, Maggini S. Vitamin C and Immune Function. Nutrients. 2017.
- Wessels I, et al. Zinc as a Gatekeeper of Immune Function. Nutrients. 2017.
- Hemilä H, Chalker E. Vitamin C for preventing and treating the common cold. Cochrane Database Syst Rev. 2013.
Individual results vary.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
