All About That Wonderful Vitamin C
Vitamin C is a water-soluble vitamin needed for the growth and repair of tissues in all parts of the body. It is necessary to form collagen, an important protein used to make skin, scar tissue, tendons, ligaments, and blood vessels.
Vitamin C is one of many antioxidants. Antioxidants are nutrients that block some of the damage caused by free radicals, which are by-products that result when our bodies transform food into energy. The build- up of these by-products over time is largely responsible for the aging process and may contribute to the development of various health conditions such as cancer, heart disease, and a host of inflammatory conditions like arthritis. Antioxidants also help reduce the damage to the body caused by toxic chemicals and pollutants such as cigarette smoke.
Vitamin C deficiency can lead to dry and splitting hair; gingivitis and bleeding gums; rough, dry, scaly skin; decreased wound-healing rate, easy bruising; nosebleeds; weakened enamel of the teeth; swollen and painful joints; anemia; decreased ability to ward off infection; and, possibly, weight gain because of slowed metabolic rate and energy expenditure. The body does not manufacture vitamin C on its own, nor does it store it. It is therefore important to include plenty of vitamin C-containing foods in one’s daily diet.
Low levels of vitamin C have been associated with a variety of conditions including hypertension, gallbladder disease, stroke, and atherosclerosis (the build-up of plaque in blood vessels that can lead to heart attack and stroke). Eating adequate amounts of vitamin C in the diet (primarily through lots of fresh fruits and vegetables) may help reduce the risk of developing some of these conditions. As an anti-oxidant, vitamin C plays an important role in protecting against the following:
• Heart Disease: Some studies suggest that vitamin C may help protect blood vessels from the damaging effects that lead to or result from the presence of atherosclerosis. For example, those with low levels of vitamin C may be more likely to have a heart attack, stroke, or peripheral artery disease, all potential outcomes of atherosclerosis. In terms of damage that can cause atherosclerosis, some studies have shown that vitamin C helps prevent oxidation of LDL (bad) cholesterol – a process that contributes to plaque buildup in the arteries.
• High Cholesterol: Information from several studies, involving only small numbers of people, suggest that vitamin C (3 glasses of orange juice per day or up to 2000 mg per day as a supplement) may help decrease total and LDL cholesterol and triglycerides, as well as increase HDL levels (the good kind of cholesterol).
• High Blood Pressure: Free radicals, the damaging by-products of metabolism mentioned earlier, are associated with higher blood pressure in studies of animals and people. Many clinicians recommend foods rich in vitamin C, particularly if you are at risk for high blood pressure.
• Common Cold: There have been a few studies suggesting that taking large doses of vitamin C supplements at the onset of cold or flu symptoms, or just after exposure to one of these viruses, can shorten the duration of the cold or ward it off altogether. Some experts suggest that vitamin C may only be useful in case of a cold if you have low levels of this nutrient to begin with. Another possibility is that the likelihood of success may be very individual – some improve, while others do not. If you are amongst the 67% of people who believe that vitamin C is helpful for your colds, there may be power in your conviction. In other words, your experience is probably more important than what the research is stating.
• Osteoarthritis: Vitamin C is essential for normal cartilage. Plus, free radicals can be produced in the joints and have been implicated in many degenerative changes in the aging body, including destruction of cartilage and connective tissue that lead to arthritis. Antioxidants appear to offset the damage caused by free radicals.
• Obesity and Weight Loss: Studies suggest that obese individuals may have lower vitamin C levels than non-obese individuals. Researchers speculate that insufficient amounts of vitamin C may contribute to weight gain by decreasing metabolic rates and energy expenditures. Many sensible weight loss programs will be sure to include foods rich in vitamin C, such as plenty of fruits and vegetables.
• Cataracts: Studies have shown that vitamin C may slow or even stop the progression of cataracts in the elderly. A recent study, for example, of women from the Nurses’ Health Study (a very large, important study that has followed women over many years) showed that women under 60 years of age who had high dietary intake of vitamin C or who had used vitamin C supplements for 10 years or more had significantly reduced chances of developing cataracts.
• Diabetes: Vitamin C may be helpful for people with diabetes in a number of ways. First, some studies suggest that people with diabetes have high levels of free radicals and low levels of antioxidants, including vitamin C. This imbalance may contribute to the fact that those with diabetes are at greater risk for developing conditions such as high cholesterol and atherosclerosis. Secondly, insulin (which is low in type 1 diabetics and does not function properly in type 2 diabetics) helps cells in the body take up the vitamin C that they need to function properly. At the same time, lots of circulating blood sugar (glucose), as is often the present in diabetics, prevents the cells from getting the vitamin C that they need, even if eating lots of fruits of vegetables. For this reason, taking extra vitamin C in the form of supplements may be helpful in those with diabetes.
Studies suggest that vitamin C may also be helpful for:
• Boosting immune system function
• Maintaining healthy gums
• Slowing progression of Parkinson’s disease
• Treating allergy-related conditions, such as asthma, eczema, and hay fever
• Relieving pain from pancreatitis; vitamin C levels are often low with this condition
• Reducing effects of sun exposure, such as sunburn or redness and even, possibly, skin cancer
• Alleviating dry mouth, particularly from antidepressant medications.
• Healing burns and wounds
Dietary Sources: Since vitamin C is not produced by the body, it must be obtained from fruits and vegetables. Some excellent sources of vitamin C are oranges, green peppers, watermelon, papaya, grapefruit, cantaloupe, strawberries, kiwi, mango, broccoli, tomatoes, brussels sprouts, cauliflower, cabbage, and citrus juices or juices fortified with Vitamin C. Raw and cooked leafy greens (turnip greens, spinach), red and green peppers, canned and fresh tomatoes, potatoes, winter squash, raspberries, blueberries, cranberries and pineapple are also rich sources of Vitamin C. Vitamin C is sensitive to light, air, and heat, so it is best to eat fruits and vegetables raw, or minimally cooked in order to retain their full vitamin C content.
Available Forms: You can purchase either natural or synthetic vitamin C, also called ascorbic acid, in a wide variety of forms. Tablets, capsules, and chewable tablets are probably the most popular, but vitamin C also comes in powdered crystalline, effervescent, and liquid forms. Vitamin C can be purchased in dosages ranging from 25 mg to 1,000 mg.
Precautions: It is important to drink plenty of fluids when taking supplemental vitamin C because it has a diuretic effect. During periods of stress (either emotional or physical), urinary excretion of vitamin C is increased. Extra vitamin C through vitamin C rich foods as well as supplements is often recommended to keep the immune system working properly during these times. While vitamin C is generally non-toxic, in high doses it can cause diarrhea, gas, or stomach upset.