Vitamin C, or ascorbic acid, is one of the most important water-soluble vitamins. Unlike other animals who can produce it themselves, humans don’t. It’s carried to the body’s tissues but not stored in the body, so we need to take it in daily via food or supplementation, or both.
Our main dietary source of vitamin C is from many fruits and vegetables, most notably citrus fruits. Not eating enough can lead to a vitamin C deficiency, with a slew of unpleasant symptoms. At the extreme, a deficiency of vitamin C can cause scurvy, which particularly affected sailors until the end of the 18th century and is characterized by swollen, bleeding gums and slow wound healing.
While rare in developed countries today, vitamin C deficiency still affects about one in twenty people. Those most at risk include:
- low-income individuals
- those who abuse alcohol
- those with limited food variety
- individuals with certain chronic diseases, including some cancer patients
Signs of vitamin C deficiency can take months to develop, and some are very subtle. The most common first signs are often low energy, fatigue, and weakness. Other signs of vitamin C deficiency include:
- rough, bumpy skin
- easy bruising
- slow wound healing
- painful, swollen joints
- weak bones
- bleeding, inflamed gums
- immune deficiency
- poor mood
- unexplained weight gain
- general inflammation in the body
Vitamin C plays multiple roles to support and maintain health and has many different benefits.
In the 1970s, Nobel prize winner Linus Pauling found that vitamin C boosts immunity, and could treat or even prevent the common cold. In my personal experience, when I feel a cold coming on, I take copious amounts of my homemade elderberry syrup, which is high in vitamin C and has been used as a cold and flu tonic for centuries. I also wallop it with high doses of supplemental C (5,000-10,000 mg a day) and it will often stop a cold in its tracks before it has even begun.
Not only is vitamin C effective to treat and prevent colds, but it is a powerful antioxidant, contributing to immune defense overall. Vitamin C deficiency results in impaired immunity and higher susceptibility to infections, including both respiratory and whole-body infections.
As an antioxidant, vitamin C is a strong detoxifier. It can neutralize and remove environmental pollutants, as well as damage from UV radiation and other pollutants. One study found that high-dose vitamin C accelerated the excretion of lead, one of the most toxic heavy metals.
Glutathione, another master detoxifier, works in conjunction with vitamin C. Adequate levels of vitamin C intake increases glutathione levels, protecting against oxidative stress in the body. It also helps reduce the risk of macular degeneration, Parkinson’s disease, and other neurogenerative disorders.
Vitamin C also has the ability to reduce chronic inflammation, which has been linked to a number of different degenerative conditions, including diabetes, obesity, and hypertension/high blood pressure.
Collagen is the primary protein in the body, contributing to glowing skin, healthy hair and nails, supple joints, and strong bones and muscles. To support collagen production, you need optimal vitamin C levels, as vitamin C interacts with amino acids to produce collagen. Lower vitamin C levels are associated with aged and photodamaged skin. Consuming significant amounts of vitamin C can improve elasticity, slow wrinkling, and offers other skin benefits as well.
My homemade skin repair serum is made with essential oils for skin support added to a base of rosehip oil, which is very rich in vitamin C. Rosehip oil is extremely nourishing to the skin, and reduces the appearance of scars and other skin damage. In South America, it is even used in hospitals to treat the wounds of burn victims.
Researchers have found that vitamin C also plays a role in joint health, preventing knee osteoarthritis, the most common form of arthritis that includes joint pain and swelling.
Vitamin C increases the bioavailability of iron, the main role of which is to increase the body’s ability to carry oxygen through the blood. When I was pregnant, I was told to cook my spinach in a cast-iron pan for maximal absorption of both iron and vitamin C.
Particularly in the form of fresh-squeezed juices, vitamin C also enhances the gut’s ability to absorb calcium.
(Sidenote: calcium and iron hinder each other’s absorption, so if supplementing, make sure not to take those two at the same time, or when eating, avoid eating dairy and spinach at the same time, for example.)
Some researchers have found that high-dose intravenous vitamin C for sepsis, an extreme reaction to infections in the body that can cause organ failure and death, has incredible recovery results.
We can see that there are many important roles vitamin C plays in the body, from immune health to detoxification to collagen production and more. To get these and other benefits, we need to make sure we’re getting enough colorful fruits and vegetables. Cooking or drying significantly reduces vitamin C content, so eat them raw when possible.
Some of the best foods rich in vitamin C include:
- citrus fruits
- red bell peppers
- brussels sprouts
- red cabbage
- sweet potatoes
So what’s the right amount of vitamin C to take?
The RDA is somewhere between 65-90 mg a day, but studies have shown that even up to 10,000 mg a day is fine.
The fact is, vitamin C is neither toxic nor harmful, so you can’t overdose on it. Any excess vitamin C in the body is excreted out in your urine. At worst case, high doses might cause a little digestive upset or diarrhea, but those seem a small price to pay for the amazing benefits vitamin C offers.