Vitamin C is a water-soluble vitamin that is naturally found in certain foods. Unlike other mammals, this antioxidant cannot be naturally produced or synthesized by humans because of a mutation in the GULO (gulonolactone oxidase) gene, therefore it needs to be added to our diets through foods and dietary supplements. Although it has many uses and benefits, Vitamin C is known best for treating the common cold1.
Other Names for Vitamin C
Vitamin C is also known as L-ascorbic acid, and more commonly referred to as ascorbic acid. However, it's important to understand that ascorbic acid is an isolated part of vitamin C; it's not the entire vitamin. If purchasing vitamin C as a dietary supplement, do your research to figure out if it is the synthetic version of ascorbic acid made in a laboratory, which is mostly derived from genetically modified (GMO) corn and rice starch, and doesn't offer the full spectrum of the nutrients and enzymes of vitamin C in its natural form. Read the label and choose products that offer vitamin C made from real superfoods.
Health Benefits of Vitamin C
Vitamin C has been found to have four main health benefits in the prevention and treatment of the following conditions:
- Common Cold: Studies2 have found that vitamin C may shorten the duration of the common cold and reduce symptom severity.
- Cancer: Research3 suggests that higher consumption of fruits and vegetables that contain vitamin C can reduce oxidative damage to cells, which may lead to cancer. Specifically, vitamin C seems to adversely affect4 lung, breast, colon or rectum, stomach, oral cavity, larynx or pharynx, and esophagus cancer.
- Cardiovascular Disease: Foods rich in vitamin C and dietary supplements have been shown to lower the chances of coronary heart disease risk5 and prevent stroke.
- Cataracts and Age-Related Macular Degeneration (AMD): Vitamin C may prevent or slow the development of these conditions, which are the primary causes of loss of vision in older adults.
Vitamin C is vital to the production of bones, teeth, skin, cartilage, blood vessels, ligaments and tendons. It facilitates the healing process of wounds and cuts and fights free radicals that cause aging.
Although studies offer mixed results on the effectiveness of vitamin C, it may be due to the fact that different doses were administered in each particular studies. Commonly, vitamin C is used to treat the following conditions:
- Gum Disease
- Human Immunodeficiency Virus (HIV) Disease
- Stomach Ulcers
- Bladder Infections
- Acne and Skin Conditions
- Stress and Fatigue
Daily Recommended Allowance
The National Institutes of Health (NHI) offers the following guide for the daily recommended allowance of vitamin C:
|0–6 months||40 mg*||40 mg*|
|7–12 months||50 mg*||50 mg*|
|1–3 years||15 mg||15 mg|
|4–8 years||25 mg||25 mg|
|9–13 years||45 mg||45 mg|
|14–18 years||75 mg||65 mg||80 mg||115 mg|
|19+ years||90 mg||75 mg||85 mg||120 mg|
|Smokers||Individuals who smoke require 35 mg/day more vitamin C than nonsmokers.|
* Adequate Vitamin C Intake (AI)
Generally, vitamin C is safe to take for everyone in the recommended amounts. Side effects may include nausea, vomiting, headache, heartburn and stomach cramps. It may be unsafe to take doses higher than 2,000 mg per day, which may lead to diarrhea and kidney stones.
How to Use Vitamin C
There are a multitude of ways to use vitamin C for health benefits. You can add vitamin C-rich foods to your diet, purchase dietary supplements with a food-based vitamin C spectrum (via capsules, tablets or powder), utilize vitamin C injectables, buy vitamin C-fortified foods or utilize vitamin C serums and creams for the skin. Some even add vitamin C powder to bath water to remove harmful chemicals and toxins.
Because vitamin C is a water-soluble vitamin, only a certain portion of its nutrients get absorbed into the bloodstream, with the rest being excreted through the urine. A source6 reported that an average of 200 mg of vitamin C was the maximum absorbed.
To help the body increase the bioavailability of vitamin C, it's recommended to take smaller doses orally. In the book, Nutrition Almanac, writer John D. Kirschmann writes that 80 percent of the vitamin is absorbed for doses under 250 mg, and 50 percent is absorbed for doses over that amount.
Vitamin C Deficiencies
Vitamin C deficiency is not common in the U.S. because most people eat a balanced diet full of fruits and vegetables. Only 7 percent of Americans7 do not get the required amounts of vitamin C. If deficiency is a concern, a doctor can perform lab work to determine vitamin C levels.8
Symptoms of Vitamin C Deficiency Include:
- Keratosis Pilaris: bumpy, "chicken skin"
- Bent or corkscrew hair growth
- Perifollicular Hemorrhage: red spots around hair follicles on the skin
- Easily bruised skin
- Wounds that take longer than usual to heal
- Swollen Joints
- Bleeding Gums
- Poor Immunity
- Albuminuria: increased protein in the urine
- Tyrosinemia: a genetic disorder in infants
- Atrial Fibrillation: regular heartbeat
- Helps with iron absorption
Risk Factors for Vitamin C Deficiency
Below are risk factors that can lead to a Vitamin C deficiency:
- Poor diet
- Intestinal problems that prohibit the absorption of vitamins
- Medications that prohibits the absorption of vitamins
- Chronic illness, such as cancer and kidney disease
- Severe Mental Illness
- Eating Disorders
Foods That Contain Vitamin C
There are many fruits and vegetables that contain natural forms of vitamin C, which include:
- Citrus fruits and fresh juices, such as orange and grapefruit
- Red and green bell peppers
- Green peas
- Strawberries, Raspberries, Blueberries and Cranberries
- Winter squash
Heating or cooking fruits or vegetables can lead to the depletion of vitamin C. To avoid this, try to purchase raw, organic and fresh foods, or grow them yourself. If cooking these raw ingredients is a necessity, steaming is the best option to preserve the nutrients found in Vitamin C.
It's important to discuss any changes in your health routine with your doctor. Prior to adding supplements or increasing vitamin doses, it can be beneficial to perform lab work to assess current levels and discuss the best options with a medical professional.