Benefits of Vitamin C

Vitamin C is one of the safest and most effective nutrients, experts say. It may not be the cure for the common cold (though it's thought to help prevent more serious complications). But the benefits of vitamin C may include protection against immune system deficiencies, cardiovascular disease, prenatal health problems, eye disease, and even skin wrinkling. A recent study published in Seminars in Preventive and Alternative Medicine that looked at over 100 studies over 10 years revealed a growing list of benefits of vitamin C.

"Vitamin C has received a great deal of attention, and with good reason. Higher blood levels of vitamin C may be the ideal nutrition marker for overall health," says study researcher Mark Moyad, MD, MPH, of the University of Michigan. "The more we study vitamin C, the better our understanding of how diverse it is in protecting our health, from cardiovascular, cancer, stroke, eye health [and] immunity to living longer." "But," Moyad notes, "the ideal dosage may be higher than the recommended dietary allowance." How Much Vitamin C Is Enough? Most of the studies Moyad and his colleagues examined used 500 daily milligrams of vitamin C to achieve health results. That's much higher than the RDA of 75-90 milligrams a day for adults. So unless you can eat plenty of fruits and vegetables, you may need to take a dietary supplement of vitamin C to gain all the benefits, Moyad says. He suggests taking 500 milligrams a day, in addition to eating five servings of fruits and vegetables. "It is just not practical for most people to consume the required servings of fruits and vegetables needed on a consistent basis, whereas taking a once-daily supplement is safe, effective, and easy to do," Moyad says. He also notes that only 10% to 20% of adults get the recommended nine servings of fruits and vegetables daily. Moyad says there is no real downside to taking a 500-milligram supplement, except that some types may irritate the stomach. That's why he recommends taking a non-acidic, buffered form of the vitamin.

"The safe upper limit for vitamin C is 2,000 milligrams a day, and there is a great track record with strong evidence that taking 500 milligrams daily is safe," he says. Still, American Dietetic Association spokeswoman Dee Sandquist, RD, suggests doing your best to work more fruits and vegetables into your diet before taking supplements. "Strive to eat nine servings of fruits and vegetables daily, because you will get a healthy dose of vitamin C along with an abundance of other vitamins, minerals, and phytochemicals that are good for disease prevention and overall health," she says. While a cup of orange juice or a half-cup of red pepper would be enough to meet your RDA for Vitamin C, here are all the foods and beverages you'd need to consume to reach 500 milligrams (mg): Cantaloupe, 1 cup: 59 mg Vitamin COrange juice, 1 cup: 97 mgBroccoli, cooked, 1 cup: 74 mgRed cabbage, 1/2 cup: 40 mgGreen pepper, 1/2 cup, 60 mgRed pepper, 1/2 cup, 95 mgKiwi, 1 medium: 70 mgTomato juice, 1 cup: 45 mg

Benefits of Vitamin A

Vitamin A, also called retinol, helps your eyes adjust to light changes when you come in from outside and also helps keep your eyes, skin and mucous membranes moist. Vitamin A mostly comes from animal foods, but some plant-based foods supply beta-carotene, which your body then converts into Vitamin A. It also has antioxidant properties that neutralize free radicals in the body that cause tissue and cellular damage.
Early information from scientific studies suggests that beta-carotene might help people who already have Coronary Artery Disease (CAD). The American Heart Association doesn't recommend taking supplements of beta-carotene until more is known, however.
Nutritionists categorize vitamins by the materials that a vitamin will dissolve in. There are two categories: water-soluble and fat-soluble vitamins. Fat-soluble vitamins—vitamins A, D, E and K—are stored in the fat tissues of the body for a few days to up to six months. If you get too much of a fat-soluble vitamin, it can be stored in your liver and may sometimes cause health problems. Vitamin A is a fat-soluble vitamin.
Some people take mega-doses of fat-soluble vitamins, which can lead to toxicity. Eating a normal diet of foods rich in these vitamins won't cause a problem. Remember, you only need small amounts of any vitamin. In the case of vitamin A, overconsumption has been linked with an increased risk of fractures in postmenopausal women.
Some health problems can make it hard for a person's body to absorb these vitamins. If you have a chronic health condition, ask your doctor about whether your vitamin absorption will be affected.
How Much Vitamin A Is Enough?It's recommended that women consume 800 mcg and men consume 1000 mcg of vitamin A daily.
Sources of Vitamin A
Top sources of vitamin A include:
Beef liver
Egg yolk
Cheddar cheese
Fortified milk
Top sources of beta-carotene include:
Sweet potato
Carrots
Pumpkin
Cantaloupe
Broccoli
Apricots
Spinach and collard greens
Can You Have Too Much or Too Little?Vitamin A deficiency is rare in the United States, but it can cause night blindness, eye inflammation, diarrhea and other problems. Overconsumption of vitamin A can cause nausea, irritability and blurred vision in its mild form. In addition, the palms of the hands and the bottoms of the feet can turn orange if a person has a high intake of Vitamin A. Vitamin A toxicity can cause growth retardation, hair loss and enlarged spleen and liver in its more severe form. Vitamin A overdose can also cause birth defects and has been linked to increased risk of bone fractures in some people.
Vitamin StorageIf you want to get the most vitamins possible from your food, refrigerate fresh produce, and keep milk and grains away from strong light. Vitamins are easily destroyed and washed out during food preparation and storage. If you take vitamin supplements, store them at room temperature in a dry place that's free of moisture.