Diff: Vitamin C
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'''Vitamin C''', also known as ascorbic acid, is a water-soluble vitamin that plays a crucial role in various physiological processes within the human body. It is renowned for its antioxidant properties, which contribute to immune system function, collagen synthesis, and overall health. Since the human body cannot produce vitamin C on its own, it must be obtained through diet or supplementation. |
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==Overview== |
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Water-Soluble Vitamin: |
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Essential Nutrient: Vitamin C is an essential nutrient, meaning it must be obtained from external sources like food or supplements. |
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Heat-Sensitive: Vitamin C is sensitive to heat and is easily destroyed during cooking and food processing. |
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Antioxidant Properties: |
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Free Radical Scavenger: Vitamin C acts as an antioxidant, neutralizing harmful free radicals and protecting cells from oxidative stress. |
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Collagen Synthesis: |
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Connective Tissue Formation: Vitamin C is vital for the synthesis of collagen, a protein essential for the structure of skin, blood vessels, bones, and other connective tissues. |
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==Functions of Vitamin C== |
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Immune System Support: |
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White Blood Cell Function: Vitamin C enhances the function of white blood cells, contributing to immune system strength. |
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Antiviral Properties: It may help reduce the severity and duration of respiratory infections. |
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Wound Healing: |
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Collagen Production: Vitamin C is essential for the formation of collagen, a key factor in wound healing and tissue repair. |
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Iron Absorption: |
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Facilitates Iron Uptake: Vitamin C enhances the absorption of non-heme iron from plant-based sources in the digestive tract. |
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Antioxidant Network: |
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Regenerates Vitamin E: Vitamin C regenerates vitamin E, another antioxidant, maximizing the body's antioxidant network. |
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'''Vitamin C''', also called ascorbic acid, is a water-soluble vitamin found in many fruit and vegetables. Humans cannot make it, so it has to come from food or supplements. It is needed for collagen formation, normal wound healing, immune function, iron absorption, and protection of cells from oxidative damage. |
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Neurotransmitter Synthesis: |
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Because vitamin C is water-soluble, the body does not store large reserves. Regular intake from food is therefore more useful than occasional large doses. |
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Dopamine and Norepinephrine: Vitamin C is involved in the synthesis of neurotransmitters like dopamine and norepinephrine. |
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==Sources of Vitamin C== |
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Fruits and Vegetables: |
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== Functions == |
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Vitamin C helps several normal body processes: |
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Citrus Fruits: Oranges, lemons, grapefruits. |
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* '''Collagen formation''': collagen is needed in skin, gums, blood vessels, bone, cartilage, and connective tissue. |
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* '''Wound healing''': collagen production is part of normal repair after injury. |
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* '''Iron absorption''': vitamin C improves absorption of non-haem iron from plant foods. |
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* '''Antioxidant activity''': vitamin C helps limit oxidative damage in cells. |
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* '''Immune function''': it supports several immune cell functions, although it is not a cure for infections. |
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* '''Enzyme reactions''': vitamin C is involved in making some hormones and neurotransmitters. |
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Berries: Strawberries, blueberries, raspberries. |
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== Food Sources == |
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Good food sources include: |
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Kiwi, Mango, Pineapple: Tropical fruits rich in vitamin C. |
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* Citrus fruit such as oranges and grapefruit. |
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* Strawberries and blackcurrants. |
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* Kiwi fruit. |
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* Peppers. |
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* Broccoli. |
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* Brussels sprouts. |
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* Potatoes. |
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* Leafy green vegetables. |
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Bell Peppers, Broccoli, Brussels Sprouts: Vegetables with high vitamin C content. |
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Vitamin C can be reduced by prolonged storage, boiling, or repeated reheating. Steaming, microwaving, or eating some fruit and vegetables raw can preserve more of it. |
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Supplements: |
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== Intake == |
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UK NHS guidance says adults aged 19 to 64 need 40 mg of vitamin C a day and should normally be able to get that amount from a varied diet. U.S. NIH guidance uses different recommended amounts, including 90 mg a day for adult men and 75 mg a day for adult women, with higher suggested intake for smokers. |
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Ascorbic Acid Supplements: Available in various forms, including tablets, capsules, and chewable tablets. |
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==Recommended Daily Intake== |
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Varied Requirements: Recommended dietary allowances vary by age, sex, and life stage. For adults, the recommended intake is generally around 90 mg for men and 75 mg for women. |
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==Deficiency and Excess== |
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Deficiency Symptoms: |
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The difference between national figures reflects different reference systems. It does not mean that one orange or one supplement dose has the same meaning in every diet. |
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Scurvy: A condition characterized by fatigue, swollen and bleeding gums, joint pain, and anaemia. |
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== Deficiency == |
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Severe vitamin C deficiency causes scurvy. Features can include tiredness, swollen or bleeding gums, easy bruising, poor wound healing, joint pain, and anaemia. Deficiency is uncommon in people with a varied diet, but risk is higher with very limited food intake, eating disorders, alcohol dependence, smoking, some gastrointestinal conditions, and severe food insecurity. |
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Excess Intake: |
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Milder low intake may not cause obvious symptoms at first. Diet history, symptoms, and sometimes blood tests can be used to assess suspected deficiency. |
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Tolerance Limits: Excessive intake can lead to digestive issues, and very high doses may cause diarrhoea. |
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==Interactions and Considerations== |
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Iron Absorption: |
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== Supplements == |
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Most people can meet their needs from food. Supplements may be useful when diet is limited or deficiency risk is high, but high-dose products are often unnecessary. |
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Enhanced Absorption: Vitamin C enhances the absorption of non-heme iron but may increase the risk of iron overload in individuals with hereditary hemochromatosis. |
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Large doses can cause diarrhoea, nausea, stomach cramps, and other digestive symptoms. People with kidney stone risk, kidney disease, iron overload conditions such as haemochromatosis, or complex medication regimens may need extra caution with high-dose supplements. |
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Medication Interactions: |
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== Common Claims == |
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Vitamin C is often marketed for colds, immunity, skin, tiredness, and general health. Evidence is mixed. Regular vitamin C supplements may slightly shorten cold duration in some studies, but taking vitamin C after cold symptoms start has not consistently shown the same benefit. Claims about preventing cancer, heart disease, or infections should be read carefully because diet, dose, population, and study type matter. |
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Aspirin and Antacids: Long-term use of aspirin or antacids may decrease vitamin C levels. |
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==Research and Health Benefits== |
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Cardiovascular Health: |
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Food sources are usually the simplest route because they provide fibre, potassium, folate, and other nutrients alongside vitamin C. |
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Heart Disease Prevention: Some studies suggest that vitamin C may contribute to cardiovascular health by reducing the risk of heart disease. |
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== See Also == |
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* [[Common_Medical_Terms]] |
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* [[Omega-3_fatty_acids]] |
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* [[Selenium]] |
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Cancer Prevention: |
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== References == |
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* [https://111.wales.nhs.uk/vitaminsandminerals/ NHS 111 Wales: Vitamins and minerals] |
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* [https://www.nhsinform.scot/healthy-living/food-and-nutrition/eating-well/vitamins-and-minerals/ NHS inform: Vitamins and minerals] |
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* [https://ods.od.nih.gov/factsheets/VitaminC-Consumer/ NIH Office of Dietary Supplements: Vitamin C consumer fact sheet] |
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* [https://ods.od.nih.gov/factsheets/VitaminC-HealthProfessional/ NIH Office of Dietary Supplements: Vitamin C health professional fact sheet] |
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Anticancer Properties: Research explores the potential role of vitamin C in preventing certain cancers. |
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[[Category:Nutrition]] |
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[[Category:Medicine]] |