Vitamin C, or ascorbic acid, is a water-soluble vitamin. This means that it dissolves in water and is delivered to the body’s tissues but is not well stored, so it must be taken daily through food or supplements. Even before its discovery in 1932, nutrition experts recognized that something in citrus fruits could prevent scurvy, a disease that killed as many as two million sailors between 1500 and 1800.
In this article, you will learn about the most common things about Vitamin C with Pritish Kumar.
Vitamin C plays a role in controlling infections and healing wounds, and is a powerful antioxidant that can neutralize harmful free radicals. It is needed to make collagen, a fibrous protein in connective tissue that is weaved throughout various systems in the body: nervous, immune, bone, cartilage, blood, and others. The vitamin helps make several hormones and chemical messengers used in the brain and nerves.
RDA: The Recommended Dietary Allowance for adults 19 years and older is 90 mg daily for men and 75 mg for women. For pregnancy and lactation, the amount increases to 85 mg and 120 mg daily, respectively. Smoking can deplete vitamin C levels in the body, so an additional 35 mg beyond the RDA is suggested for smokers.
UL: The Tolerable Upper Intake Level is the maximum daily intake unlikely to cause harmful effects on health. The UL for vitamin C is 2000 mg daily;
taking beyond this amount may promote gastrointestinal distress and diarrhea.
Only in specific scenarios, such as under medical supervision or in controlled clinical trials, amounts higher than the UL are sometimes used.
Vitamin C and Health
There is interest in the antioxidant role of vitamin C, as research has found the vitamin to neutralize free radical molecules, which in excess can damage cells. Vitamin C is also involved in the body’s immune system by stimulating the activity of white blood cells.
Although some epidemiological studies that follow large groups of people over time have found a protective effect of higher intakes of vitamin C (from food or supplements) from cardiovascular disease and certain cancers, other studies have not. Randomized controlled trials have not found a benefit of vitamin C supplements on the prevalence of cardiovascular disease or cancer. The inconsistency of the data overall prevents the establishment of a specific vitamin C recommendation above the RDA for these conditions.
Age-related vision diseases
Vitamin C has also been theorized to protect from eye diseases like cataracts and macular degeneration. Human studies using vitamin C supplements have not shown a consistent benefit, though there appears to be a strong association between a high daily intake of fruit and vegetables and decreased risk of cataracts.
The common cold
Despite being a popular fix, vitamin C’s cold-fighting potential hasn’t panned out. Reviews of several studies show that megadoses (greater than 500 mg daily) of supplemental vitamin C have no significant effect on the common cold, but may provide a moderate benefit in decreasing the duration and severity of colds in some groups of people.
Small trials suggest that the amount of vitamin C in a typical multivitamin taken at the start of a cold might ease symptoms, but for the average person, there is no evidence that megadoses make a difference, or that they prevent colds.
Fruits and vegetables are the best sources of this vitamin.
- Citrus (oranges, kiwi, lemon, grapefruit)
- Bell peppers
- Cruciferous vegetables (broccoli, Brussels sprouts, cabbage, cauliflower)
- White potatoes
|Food||Milligrams (mg) per serving||Percent (%) DV*|
|Red pepper, sweet, raw, ½ cup||95||106|
|Orange juice, ¾ cup||93||103|
|Orange, 1 medium||70||78|
|Grapefruit juice, ¾ cup||70||78|
|Kiwifruit, 1 medium||64||71|
|Green pepper, sweet, raw, ½ cup||60||67|
|Broccoli, cooked, ½ cup||51||57|
|Strawberries, fresh, sliced, ½ cup||49||54|
|Brussels sprouts, cooked, ½ cup||48||53|
|Grapefruit, ½ medium||39||43|
|Broccoli, raw, ½ cup||39||43|
|Tomato juice, ¾ cup||33||37|
|Cantaloupe, ½ cup||29||32|
|Cabbage, cooked, ½ cup||28||31|
|Cauliflower, raw, ½ cup||26||29|
|Potato, baked, 1 medium||17||19|
|Tomato, raw, 1 medium||17||19|
|Spinach, cooked, ½ cup||9||10|
|Green peas, frozen, cooked, ½ cup||8||9|
Signs of Deficiency
Vitamin C deficiency is rare in developed countries but may occur with a limited diet that provides less than 10 mg daily for one month or longer.
In developed countries, situations at greatest risk for deficiency include eating a diet restricted in fruits and vegetables, smoking or long-term exposure to secondhand smoke, and drug and alcohol abuse. The following are the most common signs of a deficiency.
- Scurvy, the hallmark disease of severe vitamin C deficiency, displays symptoms resulting from loss of collagen that weakens connective tissues:
- Skin spots caused by bleeding and bruising from broken blood vessels
- Swelling or bleeding of gums, and eventual loss of teeth
- Hair loss
- Delayed healing of skin wounds
- Fatigue, malaise
- Iron-deficiency anemia due to decreased absorption of non-heme iron
Vitamin C improves the absorption of non-heme iron, the type of iron found in plant foods such as leafy greens. Drinking a small glass of 100% fruit juice or including a vitamin-C-rich food with meals can help boost iron absorption.
Vitamin C can be destroyed by heat and light. High-heat cooking temperatures or prolonged cook times can break down the vitamin. Because it is water-soluble, the vitamin can also seep into cooking liquid and be lost if the liquids are not eaten. Quick heating methods or using as little water as possible when cooking, such as stir-frying or blanching, can preserve the vitamin. Foods at peak ripeness eaten raw contain the most vitamin C.