Vitamin C : An Immune Supporter

Vitamin C, also known as ascorbic acid, is an essential nutrient that keeps the body functioning. It is a water-soluble vitamin well known for its role in supporting a healthy immune system. Some animals can make their own vitaminC. Unlike other animals, humans cannot synthesize vitaminC on their own. Therefore, you must get enough of it from foods or supplements to maintain good health. It helps strengthen your immune system, aids collagen production and wound healing, and acts as an antioxidant to protect your cells from free radical damage. It’s water-soluble and found in many fruits and vegetables, including oranges, strawberries, kiwi fruit, bell peppers, broccoli, kale, and spinach.
Good sources of vitaminC are fresh fruits and vegetables, especially citrus fruits.

How does it work?

Vitamin-C is required for the proper development and function of many parts of the body. It also plays an important role in maintaining proper immune function. Research shows vitaminC is essential for the growth and repair of tissue all over the body. VitaminC helps heal wounds and repair and maintain healthy bones, teeth, skin and cartilage — a type of firm tissue that covers the bones.

Vitamin C : An Immune Supporter

Vitamin C is essential for overall health and wellness, and the nutrient may particularly benefit certain conditions.
The vitamin is especially helpful for immune health, as it supports your immune system’s cellular function. In fact, vitaminC supplements may help prevent infection, while a deficiency of the vitamin appears to make you more susceptible to infection. For example, some research suggests that although regular vitaminC intake likely won’t prevent you from catching a cold, it may reduce the duration or severity of cold symptoms.
A review of 31 studies found that consuming 1–2 grams of vitaminC daily reduced cold duration by 18% in children and 8% in adults. In addition, it’s known that vitaminC increases iron absorption. Thus, individuals with iron deficiency might benefit from increasing their vitaminC intake.
Hence regularly getting 1–2 grams of vitaminC per day may reduce the duration of common cold symptoms and boost your immune system. It might also help prevent iron deficiency anemia.
VitaminC helps encourage the production of white blood cells known as lymphocytes and phagocytes, which help protect the body against infection. VitaminC helps these white blood cells function more effectively while protecting them from damage by potentially harmful molecules, such as free radicals. VitaminC is an essential part of the skin’s defense system. It’s actively transported to the skin, where it can act as an antioxidant and help strengthen the skin’s barriers. Studies have also shown that taking vitaminC may shorten wound healing time.

Health Benefits

According to research from the Centers for Disease Control and Prevention (CDC), an estimated 7.1% of the U.S. population can be classified as being vitaminC deficient. Those with severe vitaminC dietary deficiency can develop scurvy, characterized by bruising, bleeding gums, weakness, fatigue, and rash.
Outside of a known deficiency, vitaminC is believed by some to aid in the treatment or prevention of numerous diseases, including colds, asthma, bronchitis, cancer, chronic pain, cataracts, gastritis, glaucoma, heart disease, high blood pressure, osteoarthritis, and Parkinson's disease.
Although the evidence supporting these claims is generally weak, there have some been several promising findings in recent years.

• May reduce your risk of chronic disease

VitaminC is a powerful antioxidant that can strengthen your body’s natural defenses. Antioxidants are molecules that boost the immune system. They do so by protecting cells from harmful molecules called free radicals. When free radicals accumulate, they can promote a state known as oxidative stress, which has been linked to many chronic diseases. Studies show that consuming more vitaminC can increase your blood antioxidant levels by up to 30%. This helps the body’s natural defenses fight inflammation.

• May help manage high blood pressure

The benefits of vitaminC in treating hypertension (high blood pressure) have long been touted, although the actual effects are not nearly as robust as once thought. High blood pressure puts you at risk of heart disease, the leading cause of death globally.
Studies have shown that vitaminC may help lower blood pressure in both those with and without high blood pressure. An animal study found that taking a vitaminC supplement helped relax the blood vessels that carry blood from the heart, which helped reduce blood pressure levels. Moreover, an analysis of 29 human studies found that taking a vitaminC supplement reduced systolic blood pressure (the upper value) by 3.8 mmHg and diastolic blood pressure (the lower value) by 1.5 mmHg, on average, in healthy adults.
In adults with high blood pressure, vitaminC supplements reduced systolic blood pressure by 4.9 mmHg and diastolic blood pressure by 1.7 mmHg, on average. According to a 2012 study from Johns Hopkins University, high doses of vitamin C—around 500 milligrams daily—produced only small reductions in the systolic (upper) blood pressure but had little effect on the diastolic (lower) blood pressure.

• May lower your risk of heart disease

Heart disease is the leading cause of death worldwide. Many factors increase the risk of heart disease, including high blood pressure, high triglyceride or LDL (bad) cholesterol levels, and low levels of HDL (good) cholesterol.
Vitamin C is often erroneously lauded for its ability to fight heart disease. Much of the misperception has been fueled by vitamin C's antioxidant properties.
For example, an analysis of 9 studies with a combined 293,172 participants found that after 10 years, people who took at least 700 mg of vitaminC daily had a 25% lower risk of heart disease than those who did not take a vitaminC supplement. Interestingly, another analysis of 15 studies found that consuming vitaminC from foods — not supplements — was linked to a lower risk of heart disease.
However, scientists were unsure whether people who consumed vitaminC-rich foods also followed a healthier lifestyle than people who took a supplement. Thus, it remains unclear whether the differences were due to vitaminC or other aspects of their diet.
Another analysis of 13 studies looked at the effects of taking at least 500 mg of vitaminC daily on risk factors for heart disease, such as blood cholesterol and triglyceride levels. The analysis found that taking a vitamin C supplement significantly reduced LDL (bad) cholesterol by approximately 7.9 mg/dL and blood triglycerides by 20.1 mg/dL.
In short, it seems that taking or consuming at least 500 mg of vitamin C daily may reduce the risk of heart disease. However, if you already consume a vitamin-C-rich diet, then supplements may not provide additional heart health benefits.

• May reduce blood uric acid levels and help prevent gout attacks

Gout is a type of arthritis that affects approximately 4% of American adults. It’s incredibly painful and involves inflammation of the joints, especially those of the big toes. People with gout experience swelling and sudden, severe attacks of pain. Gout symptoms appear when there is too much uric acid in the blood. Uric acid is a waste product produced by the body. At high levels, it may crystallize and deposit in the joints.
Interestingly, several studies have shown that vitamin C may help reduce uric acid in the blood and, as a result, protect against gout attacks. For example, a study including 1,387 men found that those who consumed the most vitamin C had significantly lower blood levels of uric acid than those who consumed the least. Another study followed 46,994 healthy men over 20 years to determine whether vitamin C intake was linked to developing gout. It found that people who took a vitamin C supplement had a 44% lower gout risk. Additionally, an analysis of 13 studies found that taking a vitamin C supplement over 30 days significantly reduced blood uric acid.

• Vision loss

There is evidence that vitamin C may slow the progression of macular degeneration, an aging-related eye disorder characterized by vision loss. A 2001 study in the Archives of Ophthalmology reported that people at high risk of the disease who took 500 milligrams of vitamin C per day, along with beta-carotene, vitamin E and zinc, slowed the progression of macular degeneration by 25% and the loss of visual acuity by 19%. A 2014 review from Tufts University further concluded that taking 135 milligrams of vitamin C daily can prevent certain types of cataracts and that doses of over 300 milligrams could reduce the risk by no less than 57%.

• Protects your memory and thinking as you age

Dementia is a broad term used to describe symptoms of poor thinking and memory. It affects over 35 million people worldwide and typically occurs among older adults. Studies suggest that oxidative stress and inflammation near the brain, spine, and nerves (altogether known as the central nervous system) can increase the risk of dementia.
Vitamin C is a strong antioxidant. Low levels of this vitamin have been linked to an impaired ability to think and remember. Moreover, several studies have shown that people with dementia may have lower blood levels of vitamin C. Furthermore, high vitamin C intake from food or supplements has been shown to have a protective effect on thinking and memory as you age.
Vitamin C supplements may aid against conditions like dementia if you don’t get enough vitamin C from your diet. However, additional human studies are needed to understand the effects of vitamin C supplements on nervous system health.

• Help prevent iron deficiency

Iron is an important nutrient that has a variety of functions in the body. It’s essential for making red blood cells and transporting oxygen throughout the body. Vitamin C can help improve the absorption of iron from the diet. Vitamin C assists in converting iron that is poorly absorbed, such as plant-based sources of iron, into a form that is easier to absorb. This is especially useful for people on a meat-free diet, as meat is a major source of iron.
In fact, simply consuming 100 mg of vitamin C may improve iron absorption by 67%. As a result, vitamin C may help reduce the risk of anemia among people prone to iron deficiency. In one study, 65 children with mild iron deficiency anemia were given a vitamin C supplement. Researchers found that the supplement alone helped control their anemia.
If you have low iron levels, consuming more vitamin-C-rich foods or taking a vitamin C supplement may help improve your blood iron levels.

What’s the recommended intake?

The Institute of Medicine (IOM) has developed a set of reference values for specific nutrient intake levels, including for vitamin C. One set of guidelines is known as the Recommended Dietary Allowance (RDA) and considers average daily nutrient intake from both foods and supplements. RDA recommendations for specific gender and age groups should meet the nutrient needs of 97–98% of healthy individuals.
Here are the RDAs for vitamin C :

Life stage	RDA
Kids (1–3 years)	15 mg
Kids (4–8 years)	25 mg
Adolescents (9–13 years)	45 mg
Teens (14–18 years)	65–75 mg
Adult women (aged 19 and older)	75 mg
Adult men (aged 19 and older)	90 mg
Pregnant women (aged 19 and older)	85 mg
Breastfeeding women (aged 19 and older)	120 mg

Do I need a vitamin C supplement?

As a general rule, it is always best to get your nutrients from food rather than pills. With that being said, taking a daily vitamin C supplement won't cause you any harm and can bolster your RDA if you happen to fall short.
If you don't think you're getting enough vitamin C in your diet, don't hesitate to supplement at the recommended dosages. At the same time, increase your intake of the following foods rich in vitamin C:

• Red pepper (raw): 95 milligrams per 1/2-cup serving
• Orange juice: 90 milligrams per 3/4-cup serving
• Orange: 70 milligrams per one medium fruit
• Kiwi: 64 milligrams per one medium fruit
• Green pepper (raw): 60 milligrams per 1/2-cup serving
• Broccoli (cooked): 51 milligrams per 1/2-cup serving
• Strawberries (sliced): 49 milligrams per 1/2-cup serving
• Brussel sprouts (cooked): 48 milligrams per 1/2-cup serving
• Tomato juice: 33 milligrams per 1/2-cup serving
• Cantaloupe: 29 milligrams per 1/2-cup serving