Strengthening your immune system with Vitamin C-rich food and supplements can help to protect you against illness. Vitamin C is one of the most potent immune boosters available.

Most people are familiar with the popular saying, “an apple a day keeps the doctor away”, and realize the many health benefits provided by vitamin C such as helping prevent or shorten colds and flu; however, many still underestimate this incredible super nutrient’s impact.

Vitamin C is an Antioxidant

Vitamin C is an antioxidant, a naturally occurring chemical found in certain foods that acts as an invisible shield for our bodies, protecting us against cancer, heart disease, aging and infection. (2)

Vitamin C (L-ascorbic acid) is a water-soluble vitamin, meaning that it dissolves in the fluids found in cells and tissues of your body. This means it plays an integral part in creating collagen as well as other proteins involved in tissue repair as well as producing certain hormones (3).

As an antioxidant, vitamin C plays an integral part in keeping harmful molecules called free radicals at bay. Free radicals can form when your body breaks down food or is exposed to toxic chemicals or pollutants such as cigarette smoke; free radicals can damage cells and promote chronic inflammation that contributes to many illnesses (4).

Your immune system relies on vitamin C to function optimally. Furthermore, vitamin C aids the body’s absorption of iron which it needs for red blood cell production and creating connective tissues (5).

Studies show that vitamin C helps your immune system fight infections like the common cold and flu more effectively, as well as reduce duration and severity of viral illnesses like chicken pox or shingles (6)

Vitamin C plays an integral part of your immune system by aiding its operation and supporting new white blood cell production, the primary means of defense against infection. Furthermore, Vitamin C strengthens skin barriers against bacteria penetration as well as increasing amounts of ionized calcium in your blood stream (7)

Lower levels of vitamin C have been associated with an increased risk of diseases, including cancer, cardiovascular disease and age-related macular degeneration. Adequate amounts are especially essential if being treated for cancer or suffering other serious medical issues like chronic renal failure – so be sure to talk to your physician about safe dosage recommendations to suit your condition(8)

It Boosts Energy Levels

Vitamin C is a water-soluble nutrient your body uses to form blood vessels, cartilage and collagen in bones. Additionally, it acts as an antioxidant, providing cells protection from disease caused by radiation exposure from sunlight as well as free radicals linked to cardiovascular disease and cancers. Vitamin C also plays an essential role in biological reactions like producing flavonoids synthesis as well as aiding non-heme iron absorption from foods (see Iron). Finally, Vitamin C boosts energy by increasing absorption of glucose into brain tissue as well as increasing red blood cell production – helping your cells remain protected and protected.

Although Vitamin C has long been considered beneficial for immune function, evidence to back this claim remains inconsistent. Studies conducted on asthmatic subjects revealed that while Vitamin C may reduce symptoms of bronchial hyperresponsiveness, it did not improve FEV1 outcomes – the primary measure of pulmonary function. Other research, however, indicates it can shorten colds by decreasing duration and severity symptoms.

It Helps to Prevent Colds

When we think of vitamin C, our minds often drift to oranges or the supplements claiming to increase immunity. But you might be amazed to find out all of its other uses! Registered dietitian Devon Peart, RD emphasizes its power for prevention as much as its ability to speed recovery from illness.

Research on Vitamin C supplementation has not demonstrated its ability to prevent colds in general populations; however, it appears to decrease symptoms when taken early on during a cold. Studies indicate that taking small amounts of Vitamin C every day prior to becoming sick could cut down its duration and severity by an estimated 10%; meaning a cold that would typically last 10 days will likely pass in 9!

Vitamin C can also be used as a treatment for colds once symptoms appear. Unfortunately, however, its use after initial symptoms have started doesn’t seem to make much difference to how long you will remain sick compared to something like flu vaccination which has been proven to reduce cold and flu attacks by 50 percent or more.

Maintaining appropriate levels of Vitamin C in your body is crucial, since your skin relies on it as an immune barrier against bacteria and pathogens entering. According to a 2023 study published in Mucosal Immunology, individuals with lower vitamin C levels were more vulnerable to infections than those who maintained normal levels.

Staying hydrated with Vitamin C means including fresh fruits and veggies in your diet regularly, such as dark leafy greens, tomatoes, berries and other fast snacks such as smoothies. Keep hummus or other low-fat dips available so that raw veggies can be quickly transformed into filling snack options that provide essential vitamins and minerals. Or for an afternoon pick-me-up try sipping vegetable juice!

It Helps to Prevent Cancer

Conventional wisdom held that vitamin C was an effective cancer preventative, by mopping up volatile oxygen free radicals before they caused damage to delicate DNA strands. A Johns Hopkins study published this week in Cancer Cell suggests this might not always be the case – at least not in ways we expected.

Researchers discovered that vitamin C interfered with tumor cells’ ability to absorb and utilize oxygen, thus starving cancerous cells of oxygen and possibly leading them to die off. Furthermore, high doses of Vitamin C taken either intravenously (IV) or orally have shown to significantly slow or stop cancer cell growth.

While most clinical trials have failed to demonstrate that vitamin C in its oral form can prevent or treat cancer, researchers are exploring whether IV vitamin C could provide an alternative therapy. They’ve discovered that high doses given intravenously can produce blood levels 100 – 500 times greater than when taken orally by bypassing normal digestive pathways and excretion pathways and reaching its maximum concentration within the body; where it may kill cancerous cells while supporting white blood cells that fight them off.

The University of Iowa team found that some types of cancer cells respond more favorably to high-dose vitamin C treatment than others, suggesting they could predict which patients could gain benefit from such an approach. Researchers discovered that cancer cells with lower concentrations of an enzyme called catalase responded better; those with higher levels were less receptive.

Though this research is exciting, its implementation remains early days for this form of therapy. People living with cancer should continue to consume adequate dietary sources of vitamin C while consulting their doctor before supplementation is considered. High doses IV vitamin C could result in dangerously low potassium levels in the body as well as interactions with certain chemotherapy drugs including protease inhibitors such as indinavir (Crixivan) and rifampicin (Rifadin). (PDQ is provided as a service by the National Cancer Institute).