Vitamin C

Vitamin C (scientifically referred to as ascorbic acid) is one of the thirteen essential vitamins required for bodily health. For years, various brands of orange juice have touted their products as excellent sources of vitamin C in their advertisements, and since the 1990s, manufacturers of vitamin supplements have promoted vitamin C as a booster of the immune system. Unlike vitamin D, which the body naturally produces, vitamin C is not produced by the body and can only be obtained through consumption of foods, beverages, and supplements. Among the best sources of vitamin C are tropical and citrus fruits, strawberries, and tomatoes. Other vitamin C-rich foods include broccoli, spinach, peas, and cauliflower. Persons who suffer from lack of vitamin C intake may develop mild to severe health defects, depending on how long they have been deprived of this essential component.

Background

The recommended daily allowance (RDA) for vitamin C, which has been established by the US federal government, is 90 mg for adult males and 75 mg for adult females. However, pregnant and lactating women are recommended to up their vitamin C intake to 85 and 120 mg per day, respectively, while smokers are recommended to increase their consumption of vitamin C by 35 mg per day, regardless of sex. In the United States, fruit juices and cereals are often fortified with vitamin C, which increases the levels of the vitamin in these products. Vitamin C serves to help maintain the body’s immune system, which fights off infections, as well as producing the protein collagen (which is found in skin, bone, tendons, and blood vessels). Vitamin C is also essential in freeing the body of free radicals, which are harmful byproducts that are produced when the body metabolizes oxygen. Free radicals cause damage to the membranes of cells if they are not removed. Additionally, vitamin C helps the body absorb iron, a mineral that helps with bodily growth and proper functioning of cells.

Lack of sufficient vitamin C intake leads to a medical condition known as scurvy, which is relatively easy to treat but can lead to serious health consequences and death if left untreated for a prolonged period of time. Scurvy typically develops when a person obtains less than 10–15 mg of vitamin C in their diet for several weeks. Early symptoms of scurvy include feelings of tiredness, mood swings, weight loss, and sore gums. These early symptoms are frequently mistaken for a common cold, but if scurvy persists for many weeks or a few months, much more serious complications often develop, such as swollen and bleeding gums, loosening of the teeth, skin that bruises and easily bleeds, a weakened immune system, gingivitis, and excessively dry skin and hair.

Scurvy was a serious concern for sailors during the sixteenth, seventeenth, and eighteenth centuries, when long journeys across oceans for weeks or months on end limited their opportunities to eat fresh fruits and vegetables that would have provided them with vitamin C. Today scurvy is a relatively rare disease, especially in the industrialized world, although it still occurs. For example, the British Broadcasting Corporation reported that an eight-year old Welsh child died of scurvy in December 2011, drawing attention to a disease that had not garnered significant media coverage in decades. Doctors treat scurvy by prescribing patients with supplements that contain approximately 3–4 times the recommended daily allowance for vitamin C for a certain period of time.

Overview

Research has revealed that cooking vegetables may lower some of the vitamin C content in these foods. As such, consuming vegetables raw ensures that the maximum level of vitamin C is obtained. One of the most important aspects of vitamin C is that it is a water-soluble vitamin, meaning that it dissolves in water and the body will eventually flush out vitamin C in urine. As a result, people need to continually obtain vitamin C through their diet on a regular basis (preferably daily).

Although most of the health dimensions pertaining to vitamin C have historically focused on problems caused by lack of vitamin C, excessive intake of this vitamin also has negative effects. Clinical studies indicate that humans can usually consume up to 2,000 mg of vitamin C daily with no harmful side effects. However, vitamin C intake greater than this amount can result in severe abdominal cramping, diarrhea, acidic urine, and nausea. These traits can be overcome by simply consuming less vitamin C.

During the 1980s, 1990s, and early 2000s, drug and medicine manufacturers often marketed vitamin C supplements as a low-cost but highly effective method of preventing colds and flus. However, scientific studies in the 2010s and 2020s have refuted such claims. Vitamin C supplements do nothing to prevent an individual from getting sick, although high levels of vitamin C consumption over a lengthy period of time might help to slightly reduce or lessen the severity of a cold or flu. This effect is not seen if vitamin C intake begins only after the cold begins.

Another major area of debate that has surrounded vitamin C for many years has revolved around the extent, to any, that it plays in preventing cancers from developing. This remains a hotly debated and controversial medical topic, as both sides have pointed to various clinical studies that they claim support their position.

Bibliography

Higdon, Jane. "Vitamin C." Linus Pauling Institute Micronutrient Information Center, Oregon State University, 2018, lpi.oregonstate.edu/mic/vitamins/vitamin-C. Accessed 14 Nov. 2024.

Johnson, Larry E. "Vitamin C Toxicity." Merck Manual Professional Version, Aug. 2024, www.merckmanuals.com/en-ca/professional/nutritional-disorders/vitamin-deficiency-dependency-and-toxicity/vitamin-c-toxicity. Accessed 14 Nov. 2024.

"Vitamin C." MedlinePlus, US National Library of Medicine, 19 Jan. 2023, medlineplus.gov/ency/article/002404.htm. Accessed 14 Nov. 2024.

"Vitamin C: Fact Sheet for Health Professionals." Office of Dietary Supplements, National Institutes of Health, 26 Mar. 2021, ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/. Accessed 14 Nov. 2024.