Vitamin C: Essential Protection for the Winter and Beyond

In an era of astounding scientific breakthroughs—where healthy babies are crafted from the genes of three parents and we use CT scans to analyze 99- million-year-old baby bird hatchlings preserved in amber—we can sometimes forget the simple things. That includes the well-known goodness of vitamin C, famous for preventing the fatal disease scurvy in 18th century sailors and for winning the unbridled enthusiasm of two-time Nobel winner Linus Pauling.

Vitamin C—also known as ascorbic acid—is one of those essential nutrients that we cannot synthesize ourselves. It is a water soluble molecule and must be obtained from our diet or from supplements. It is absorbed in our small intestine about 2-3 hours after we consume it, and distributed from the blood through the entire extracellular space, though it is most highly concentrated in the liver, brain, and skeletal muscle.1 Vitamin C has been shown to be important in immune function, wound healing, mood, allergies, and more.2,3,4

Vitamin C works its magic as an “electron donor”—when it donates electrons, it offers energy to fifteen different enzymes that are crucial for many functions in mammals.5 When an oxidized molecule gains an electron, it not only gains energy—it is then stabilized and called “reduced.” By donating electrons to oxidized molecules, vitamin C can function as a powerful antioxidant.6 In fact, vitamin C is one of the most potent water-soluble antioxidants in the body.7 The vitamin not only scavenges free radicals, it also reduces lipid peroxidation of cellular membranes, and supports other important antioxidants, including vitamin E and glutathione.8,9 It is essential for collagen synthesis, as well as the synthesis of carnitine and important neurotransmitters.10

You might think you get enough vitamin C from your diet—after all, it is abundant in foods ranging from strawberries to oranges, grapefruits, papaya, broccoli, kale and more. However, low dietary intake and plasma concentrations of the vitamin are surprisingly common. One survey of over 7,000 Americans found that 8.2% of males and 6% of females had such low concentrations of vitamin C in their blood they could actually experience symptoms of scurvy.11 In addition, the vitamin is depleted by smoking, serious illness, and heart attacks.12,13

Increasing our vitamin C intake can have many beneficial effects. The vitamin can help prevent, as well as decrease the severity of infections, particularly the common cold. Vitamin C along with zinc has been shown to reduce symptoms of the common cold over a five day period.14 Nearly 150 animal studies have shown that vitamin C may alleviate or prevent infections caused by bacteria, viruses, and protozoa. It has been shown to reduce the number of colds in physically active people by half, and shorten the duration of colds as well; also helping to prevent pneumonia in two studies.15 In addition, case reports suggest it may help ameliorate outbreaks of herpes zoster (commonly called shingles), as well as reduce the painful neuralgia associated with it.16,17

Vitamin C can improve the function of the immune system’s first line of defense, natural killer cells.18Neutrophils, which when activated produce oxidants such as ozone and hydrogen peroxide that kill pathogenic bacteria, rapidly absorb vitamin C, increasing their concentrations as much as ten times.19

Vitamin C may be necessary for a healthy response to stress. It is necessary to help our adrenal glands synthesize several hormones and neurotransmitters. In fact, the adrenals are one of the organs with the highest concentration of vitamin C, and they actually secrete the vitamin in response to the stress hormone, adrenocorticotrophic hormone (ACTH).20

Stress can impact mood, so it’s not surprising to learn that vitamin C is also important in balancing mood. The vitamin enhances the production of the feel-good, energizing neurotransmitter norepinephrine.21Deficiency of vitamin C has been linked to lower levels of metabolites of two major mood-enhancing neurotransmitters, dopamine and serotonin.22 Low plasma ascorbic acid levels correlate with major depression.23 Vitamin C also appears to reduce anxiety and depression in double-blind, randomized, placebo-controlled trials.24,25 The vitamin has even been shown to improve mood in hospitalized patients.26

When we take conventional vitamin C by mouth as a supplement, absorption actually decreases with increasing dosage due to gastrointestinal saturation. A liposomal delivery form can circumvent that loss and enable effective high-level dosing without intravenous therapy.27,28 In addition, sodium ascorbate, a mineral salt of ascorbic acid, is buffered and generally better tolerated than regular ascorbic acid supplements by those with gastrointestinal sensitivity.

Vitamin C’s diverse benefits show just how versatile and fundamental this simple, water-soluble molecule really is. As an electron donor, vitamin C is essential to the exchange of energy throughout your body. It is also necessary for recycling and recharging other antioxidants to control free radical damage. No wonder it impacts everything from your immune system to your mood.


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