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Vitamin C

What is Vitamin C?

Vitamin C (ascorbic acid and ascorbate) is a water-soluble vitamin found in many fruits mainly citrus fruit and vegetable sources. Many dietary supplements and topical serums of vitamin C are sold in the market to treat melasma, wrinkles on the face, and other skin problems.

Vitamin C (ascorbic acid) sources in dietary fruits, citrus fruits and vegetables with supplement, uses, deficiency

Humans do not synthesize their own vitamin C and must acquire it from dietary sources and supplements. It is an antioxidant and essential nutrient required for the functioning of several enzymes and maintaining our immune system.

The name vitamin C always refers to the l-enantiomer of ascorbic acid and its oxidized form dehydroascorbate (DHA).

Vitamin C ascorbic acid and dehydroascorbic acid sources and supplements with uses, benefits, and deficiency

Ascorbic acid is a weak acid structurally related to glucose. In biological systems, ascorbic acid can be found only at low pH but in solutions above pH 5 is predominantly found in the ionized form of ascorbic acid such as ascorbate.

Sources of Vitamin C

The richest natural sources of vitamin C are fruits and vegetables but it is widely taken as a dietary supplement. It dissolves in water and is delivered to cells of our body but is not well stored. Hence we must take it daily through food or supplements.

Ascorbic acid is sensitive to light and heat. Therefore, high heat cooking temperatures or prolonged cooking times can break down the vitamin.

The vitamin can also seep into cooking liquid because it is a water-soluble vitamin. It may be lost if the liquids are not eaten. Therefore, quick heating methods and using little water may preserve this vitamin.

The most common fruits and vegetable sources of this vitamin are given below in the table,

(mg / 100g)
(mg / 100g)
Camu camu 2800 Kale 120
Rosehip 426 Broccoli 90
Guava 228 Green bell pepper/capsicum 80
Strawberry 60 Cauliflower 48
Papaya 60 Cabbage, spinach 30
Orange, lemon 53 Potato 20
Mango 28 Tomato 14
Cranberry 13 Onion 7.4
Blueberry, grape 10 Carrot, asparagus 6

Recommended Amounts

RDA’s recommended dietary allowance of vitamin C for adults (19 years and older) is 90 mg daily for men and 75 mg for women. It may be increased during pregnancy and lactation. The recommended amount during pregnancy is 85 mg daily and for lactation 120 mg daily.

Smoking can decrease the ascorbic acid levels in our bodies. Therefore, an additional 35 mg beyond the RDA suggestion may be used for smokers. The Tolerable Upper Intake Level set by the U.S. National Academy of Sciences is 2000 mg daily. Beyond this level may promote gastrointestinal distress and diarrhea.

Vitamin C supplements

It may be found in either natural or synthetic vitamin C or ascorbic acid. Tablets and capsules are probably the most popular forms but they may also come in crystalline powdered, effervescent, and liquid forms. It comes in doses ranging from 25 mg to 1,000 mg.

Buffered vitamin C is a highly absorbable form found together with the buffering minerals magnesium, potassium, and calcium. In this way, we use higher doses of this vitamin without any stomach upset.

The most commonly used supplement molecules are ascorbic acid, sodium, and calcium ascorbate. The best way to take this vitamin supplement is 2 – 3 times per day with meals. Some studies suggest that adults should take 250 – 500 mg twice a day for any beneficial results.

Always talk to your doctor before taking a higher dose of this vitamin on a daily basis and before giving it to your child.

Vitamin C for Skin

Ascorbic acid is a water-soluble vitamin and nutrient that plays an important role in keeping your skin healthy. It is an antioxidant that fights against harmful toxic materials that come in contact with your skin either from external sources or from inside the body. Vitamin C may give the following main benefits for your skin:

  • Reduce undereye circles
  • Collagen production
  • Treats hyperpigmentation
  • Hydrates skin
  • Reduces redness

Reduce Undereye Circles

Dark circles under your eyes are common problems among people of all ages of the world. They are mainly caused by aging, genetics, allergies, or not getting enough sleep.

Many clinical studies and research show that vitamin C helps to reduce and prevent dark circles under your eyes by strengthening the skin under the eyes.

Collagen Production

Vitamin C is absolutely essential for producing collagen in the human body. Collagen is a fibrous protein in connective tissue that use to maintain the nervous, immune, bone, cartilage, blood, and other systems in our body.

The fibrous protein collagen is the building block of skin, hair, muscles, and tendons. Therefore, it keeps our skin looking youthful and smooth.

Treats Hyperpigmentation

Hyperpigmentation is a common problem that develops darker spots on the skin and is caused mainly by overexposure to the sun’s ultraviolet (UV) rays and environmental stresses.

Various study shows that the antioxidant properties of ascorbic acid reduce unwanted dark spots and prevent signs of aging caused by sun damage. It also helps to inhibit the production of tyrosinase, an enzyme useful in the production of melanin which prevents hyperpigmentation.

Hydrates Skin

Hydration is an important factor in keeping your skin healthy and youthful-looking. Without sufficient moisture, the top layer of skin starts to dry out. It leads to itchy, scaly skin and aging signs. Ascorbic acid retains water in the skin and maintenance your skin from becoming dry and oily.

Vitamin C derivative, magnesium ascorbyl phosphate is used in various skin care products that hydrate your skin. Various other supplements containing this vitamin showed significant and sustainable improvements in skin hydration.

Reduces Redness

Vitamin C has anti-inflammatory properties and helps to reduce the redness and swelling from your skin that comes with acne. The results are more pronounced when you use vitamin A and vitamin C topically.

Uses of Vitamin C

Vitamin C is one of many antioxidants that help to protect our cells against the effects of free radicals. These free radicals are produced during the breakdown of food or when our bodies are exposed to tobacco smoke and radiation coming from the sun or other sources.

Free radicals might play a role in heart disease, cancer, and other medical conditions. The buildup of free radicals in our bodies over time is responsible for signs of aging. It also helps our body to absorb and store non-heme iron. This vitamin helps to make various hormones and chemical messengers that are used in our brains and nerves.

We need to get vitamin C from our diet because our body doesn’t produce and store it. It is found in many fruits and vegetables or we use oral supplements in the form of capsules and chewable tablets.

The use of vitamin C for specific medical conditions is given below,

Vitamin C for Scurvy

Scurvy is the most common disease that causes due to vitamin C deficiency. It may cause anemia, bleeding gums, bruising, and poor wound healing.

Scurvy is easily treated by adding some vitamin C to your diet such as fresh fruits, vegetables, and supplements until you feel better. Most people feel better within 48 hours and make a full recovery within 2 weeks.

Heart Disease

Some studies have suggested that vitamins E and C may reduce the risk of heart disease but larger clinical trials may not show beneficial effects. It does not lower cholesterol levels or reduce the overall risk of a heart attack but it may help protect arteries against damage.

The American Heart Association does not recommend the way to take any vitamin to prevent heart disease.

High Blood Pressure

Population-based studies show that people who eat fruits and vegetables rich in vitamin C and antioxidants can reduce the risk of high blood pressure. Therefore, eating foods rich in ascorbic acid is an important factor for your overall health especially if you are at risk for high blood pressure.

For the treatment and prevention of high blood pressure, your diet physicians most frequently recommend taking lots of antioxidants that come from various fruits and vegetables.


Eating a diet rich in fruits and vegetables might lower the risk of breast, colon, and lung cancers. There is no evidence that vitamin C present in such fruits and vegetables reduces the risk of cancer.

Taking oral vitamin C capsules and chewable tablets doesn’t appear to offer the same benefit as dietary implementation gives.

Common Cold

We have the popular belief that taking oral vitamin C supplements (capsules and chewable tablets) may prevent the common cold but scientific evidence doesn’t support that theory. Taking this vitamin supplement regularly produces only a small reduction in the duration of a cold.

Iron Deficiency

Vitamin C improves the absorption of non-heme iron found in plant foods such as leafy greens.

Drinking a small glass of fruit juice or food supplements that contain this vitamin can help to boost iron absorption. It reduces iron to form a more soluble ferrous state which is more easily absorbed.

Eye diseases

Taking oral vitamin C supplements in combination with zinc, beta-carotene, and vitamin E seems to protect the eyes against developing age-related macular degeneration (AMD). AMD is a leading cause of legal blindness in people over 55 in the United States.

Some studies suggest that people who have higher levels of vitamin C and other antioxidants in their diets have a lower risk of developing age-related macular degeneration (AMD).

Vitamin C Deficiency

Like other vitamins and minerals, it is an essential nutrient for our good health. Therefore, we consume vitamin C reached foods and supplements regularly to prevent deficiency. Deficiency is relatively rare in developed countries due to the availability of fresh vitamin C reached foods and supplements but it still affects roughly 7% of adults in the United States.

The most common risk factors for such deficiency are poor diet, alcoholism, anorexia, severe mental illness, smoking, and medication.

Scurvy is a most common disease that forms due to vitamin C deficiency. Without this vitamin, collagen made by the body is too unstable to perform its biological function. The deficiency also inhibits the activity of several other enzymes in the body.

The 15 most common signs and symptoms of vitamin C deficiency might include:

  1. Rough and bumpy skin
  2. Developing corkscrew-shaped body hair
  3. Bright red hair follicles
  4. Red spots or lines of fingernails
  5. Dry and damaged skin
  6. Easy bruising
  7. Slowly healing wounds
  8. Painful and swollen joints
  9. Weak bones
  10. Bleeding in gums and tooth loss
  11. Poor immunity system
  12. Developing iron deficiency anemia
  13. Fatigue and poor mood
  14. Unexpected weight gain
  15. Chronic inflammation and oxidative stress

Side Effects of Vitamin C

It is a water-soluble vitamin and dietary excesses are not absorbed. Any excesses in the blood are rapidly excreted through urine. Therefore, it shows very low toxicity. More than two to three grams of supplements may cause indigestion, particularly during an empty stomach.

Taking sodium ascorbate and calcium ascorbate forms of this vitamin may minimize the side effects. High levels of vitamin C intake may cause nausea, abdominal cramps, diarrhea, and excessive absorption of iron.