The Scientific Name: Ascorbic Acid
Vitamin C is the common name for the essential nutrient scientifically known as ascorbic acid. The term “ascorbic” itself is derived from the Greek a- (meaning “no”) and scorbutus (meaning “scurvy”), directly referencing its ability to prevent and cure this historical disease. Humans, unlike most other mammals, cannot synthesize their own vitamin C and must obtain it from their diet. Its classification as a vitamin was cemented in the 1930s following its isolation and synthesis.
The Discovery and History
The search for the cause of scurvy was a long and arduous process, primarily involving observations by naval surgeons. In the mid-1700s, British naval physician Sir James Lind famously demonstrated that citrus fruits could cure the disease in sailors, though the underlying reason remained unknown for over 150 years. It was Albert Szent-Györgyi's research into biological oxidation that ultimately led to the isolation of the active compound, which he initially called “hexuronic acid.” After a collaboration with J.L. Svirbely, it was definitively proven that this substance was the elusive vitamin C, and it was officially named ascorbic acid in 1933. For his contributions, Szent-Györgyi was awarded the Nobel Prize in Medicine in 1937.
The Function of Ascorbic Acid in the Body
As a powerful antioxidant, ascorbic acid protects cells from damage caused by free radicals, unstable molecules created during normal bodily processes and environmental exposure. Beyond its antioxidant properties, it is an essential co-factor for many enzymes and plays a crucial role in several biological functions:
- Collagen Synthesis: Ascorbic acid is vital for the hydroxylation of proline and lysine, two amino acids necessary for forming a stable, triple-helical structure of collagen. Collagen is the most abundant protein in the body, providing structural integrity to skin, bones, cartilage, and blood vessels. Deficiency leads to weakened connective tissues, a hallmark of scurvy.
- Immune System Support: It helps stimulate the function of various immune cells, such as neutrophils and lymphocytes, enhancing the body's overall defense system. Levels of vitamin C in the blood and immune cells decline rapidly during infection and stress, highlighting its importance during these times.
- Iron Absorption: Ascorbic acid significantly enhances the absorption of nonheme iron from plant-based foods by reducing it to a more soluble form in the small intestine. This is particularly important for individuals on vegetarian or vegan diets.
- Neurotransmitter Synthesis: It is a co-factor for the enzyme dopamine-beta-hydroxylase, which converts dopamine to norepinephrine, a crucial neurotransmitter for nerve function.
Dietary Sources of Vitamin C
Since the human body cannot produce ascorbic acid, it must be obtained from dietary intake. The best sources are fresh fruits and vegetables, as high temperatures during cooking can destroy the vitamin. Excellent sources include:
- Citrus fruits (oranges, grapefruit)
- Red and green bell peppers
- Kiwifruit
- Strawberries
- Broccoli
- Brussel sprouts
- Tomatoes
- Potatoes
- Papaya
Forms of Ascorbic Acid: A Comparison
Ascorbic acid is available in various supplemental forms, each with unique properties. While natural sources are generally preferred, supplements can be useful for those with increased needs or inadequate dietary intake.
| Feature | Natural Ascorbic Acid (from food) | Synthetic Ascorbic Acid (supplements) |
|---|---|---|
| Bioavailability | Excellent; accompanied by other nutrients like flavonoids. | Equivalent to natural form in simple ascorbic acid, but can vary with other formulations. |
| Cost | Varies based on seasonal produce availability. | Generally inexpensive for basic ascorbic acid; higher for specialized blends. |
| Absorption Rate | Absorbed along with dietary components, which may slow intake. | Can be rapid, especially with high-dose supplements, leading to urinary excretion of excess. |
| Effectiveness | Highly effective at preventing deficiency and providing a full spectrum of benefits. | Effectively raises blood vitamin C levels; some studies question if it provides the same breadth of benefits as whole food sources for certain conditions. |
| Side Effects (high dose) | Very low risk of side effects from food, as intake levels are self-limiting. | High doses (>2,000 mg/day) can cause gastrointestinal upset, cramps, and diarrhea. |
Deficiency and Associated Symptoms
Severe and prolonged deficiency of ascorbic acid leads to scurvy, a disease historically linked to malnutrition. Symptoms appear after several weeks of very low intake and can include:
- General weakness, fatigue, and irritability
- Widespread bruising (due to capillary fragility)
- Swollen, bleeding gums and loose teeth
- Poor wound healing and reopening of old wounds
- Dry, rough, or scaly skin
- Joint and muscle pain
- Corkscrew hairs, and skin hemorrhages around hair follicles
While frank scurvy is rare in developed countries, mild deficiency can still occur in certain populations, such as smokers, those with limited dietary variety, and individuals with alcohol dependence. Fortunately, scurvy is easily treated with oral vitamin C supplementation and increased dietary intake.
Conclusion
Vitamin C, or ascorbic acid, is a fundamental micronutrient that is indispensable for human health. Its anti-scorbutic properties have been known for centuries, though its chemical identity was only confirmed in the 20th century. The compound’s role as a potent antioxidant and a key co-factor in crucial processes like collagen and neurotransmitter synthesis makes it vital for maintaining healthy skin, strong immunity, and overall well-being. By understanding what is the name of vitamin C known as and its many functions, individuals can better appreciate the importance of consuming fresh, nutrient-rich foods to ensure adequate daily intake.
To learn more about the history and discovery of ascorbic acid, you can read about the work of Albert Szent-Györgyi on the American Chemical Society website.
