Vitamin C can then disarm the free radicals. Antioxidants are able to neutralize marauders such as free radicals by giving up some of their own electrons. When a vitamin C or E molecule makes this sacrifice, it may allow a crucial protein, gene, or cell membrane to escape damage. This helps break a chain reaction that can affect many other cells.
Each of the nutrients that has antioxidant properties also has numerous other aspects and should be considered individually. The context is also important—in some settings, for example, vitamin C is an antioxidant, and in others it can be a pro-oxidant.
Articles and advertisements have touted antioxidants as a way to help slow aging, fend off heart disease, improve flagging vision, and curb cancer. And laboratory studies and many large-scale observational trials the type that query people about their eating habits and supplement use and then track their disease patterns have noted benefits from diets rich in certain antioxidants and, in some cases, from antioxidant supplements.
But results from randomized controlled trials in which people are assigned to take specific nutrients or a placebo have failed to back up many of these claims. One study that pooled results from 68 randomized trials with over , participants found that people who were given vitamin E, beta carotene, and vitamin A had a higher risk of death than those who took a placebo.
There appeared to be no effect from vitamin C pills and a small reduction in mortality from selenium, but further research on these nutrients is needed.
These findings suggest little overall benefit of the antioxidants in pill form. On the other hand, many studies show that people who consume higher levels of these antioxidants in food have a lower risk of many diseases. The bottom line? Eating a healthy diet is the best way to get your antioxidants. This holiday season alone, millions of people will turn to HelpGuide for free mental health guidance and support. So many people rely on us in their most difficult moments.
Can we rely on you? All gifts made before December 31 will be doubled. Cookie Policy. Essential nutrients for your body Every day, your body produces skin, muscle, and bone. Micronutrients with a big role in the body Vitamins and minerals are often called micronutrients because your body needs only tiny amounts of them.
Here are a few examples of diseases that can result from vitamin deficiencies: Scurvy. Old-time sailors learned that living for months without fresh fruits or vegetables—the main sources of vitamin C—causes the bleeding gums and listlessness of scurvy.
In some developing countries, people still become blind from vitamin A deficiency. A deficiency in vitamin D can cause rickets, a condition marked by soft, weak bones that can lead to skeletal deformities such as bowed legs.
Partly to combat rickets, the U. Some examples of these benefits: Strong bones. A combination of calcium, vitamin D, vitamin K, magnesium, and phosphorus protects your bones against fractures. Prevents birth defects. Taking folic acid supplements early in pregnancy helps prevent brain and spinal birth defects in offspring.
Healthy teeth. The mineral fluoride not only helps bone formation but also keeps dental cavities from starting or worsening. The difference between vitamins and minerals Although they are all considered micronutrients, vitamins and minerals differ in basic ways.
Interacting—in good ways and bad Many micronutrients interact. A closer look at water-soluble vitamins Water-soluble vitamins are packed into the watery portions of the foods you eat. Absorption of fat-soluble vitamins. Food containing fat-soluble vitamins is ingested. The food is digested by stomach acid and then travels to the small intestine, where it is digested further. Bile is needed for the absorption of fat-soluble vitamins. This substance, which is produced in the liver, flows into the small intestine, where it breaks down fats.
Nutrients are then absorbed through the wall of the small intestine. It is usually better to get the nutrients you need from food, rather than a pill. Most older people can get all the nutrients they need from foods.
He or she may recommend a vitamin or dietary supplement. If you do need to supplement your diet, look for a supplement that contains the vitamin or mineral you need without a lot of other unnecessary ingredients. Read the label to make sure the dose is not too large.
Avoid supplements with mega-doses. Your doctor or pharmacist can recommend brands that fit your needs. Sodium is another important mineral. Whenever you add salt to your food, you're adding sodium.
We all need some sodium, but too much over time can lead to high blood pressure , which can raise your risk of having a heart attack or stroke.
How much sodium is okay? People 51 and older should reduce their sodium intake to 2, mg each day. That is about one teaspoon of salt and includes sodium added during manufacturing or cooking as well as at the table when eating.
Preparing your own meals at home without using a lot of processed foods or salt will allow you to control how much sodium you get. If you make this change slowly, you will get used to the difference in taste.
Eating more fresh vegetables and fruit also helps — they are naturally low in sodium and provide more potassium. Get your sauce and dressing on the side and use only as much as you need for taste. Read about this topic in Spanish. Food and Drug Administration toll-free druginfo fda. Dietary Guidelines for Americans DietaryGuidelines usda. NIA scientists and other experts review this content to ensure it is accurate and up to date.
Vitamins and minerals are two of the main types of nutrients that your body needs to survive and stay healthy. Find information on some of the essential vitamins recommended for older adults and how to get the recommended amount within your diet. If you are over age 70, you need at least 20 mcg IU , but not more than mcg 4, IU. If you are age 51—70, you need at least 15 mcg IU each day, but not more than mcg 4, IU.
You can get vitamin D from fatty fish, fish liver oils, fortified milk and milk products, and fortified cereals. Vitamin B12 2. You can get this vitamin from meat, fish, poultry, milk, and fortified breakfast cereals. Some people over age 50 have trouble absorbing the vitamin B12 found naturally in foods.
They may need to take vitamin B12 supplements and eat foods fortified with this vitamin. See Table 1 for a comparison of vitamins and minerals. Calcium is necessary for strong bones and health, is needed for blood to clot, and helps nerves to send messages and muscles to contract.
People of all ages are encouraged to meet their recommended dietary allowance for calcium Online Table 2 , particularly those at highest risk for low calcium intake from food: children 9 years and older, adolescent girls, adult women, and adults 51 years and older. Iron, which is necessary for transporting oxygen in the blood and important for generating energy from nutrients, is an essential mineral naturally present in some foods, such as lean meats and seafood, nuts, beans, and fortified foods.
Groups at risk of an iron deficiency include pregnant women, infants and young children, teenage girls, and premenopausal women. If your blood iron level is low, your doctor might recommend an iron supplement. Take an iron supplement as directed to avoid overdosing, which can lead to serious adverse effects. It is especially important that iron supplements be stored out of reach of children, as an iron overdose in children can be highly toxic—even fatal.
Vitamins B and C are water-soluble and move around the body more easily than fat-soluble vitamins. Water-soluble vitamins are not stored in the body; you need a continuous supply of them in your diet. When taken in excess, water-soluble vitamins are removed from the body through urine.
Vitamins A, D, E, and K, the fat-soluble vitamins, bind to fat in the stomach and are then stored in fatty tissues and the liver. These vitamins are not excreted readily, and when taken in excess, they can build up in the body and lead to unwanted, and potentially dangerous, adverse effects.
Antioxidants are substances that may prevent or delay some types of cell damage by counteracting free radicals— chemicals that can harm cells. Examples of antioxidants include vitamins A, C, and E; beta carotene; lycopene; and selenium. Although antioxidants naturally found in fruits, vegetables, and grains may help to prevent certain diseases, research has not shown that high doses of antioxidant supplements prevent disease. Widely known for its importance to good vision, vitamin A also supports the immune system and is necessary for a healthy pregnancy.
Vitamin A deficiency is rare in the United States; it is largely a problem of developing countries. Vitamin A can come from both plant and animal sources. Plant sources include leafy green vegetables and orange and yellow fruits and vegetables. Animal sources include liver, salmon, and whole milk. Vitamin A is also added to fortified cereals, is a part of most multivitamins, and is available as a stand-alone supplement.
The B complex family of vitamins is made up of 8 B vitamins, each of which performs a different important function throughout the body Online Table 3. Cereals, whole grains, enriched refined grains, potatoes, pork, seafood, liver, and kidney beans. Helps the body produce energy; affects enzymes that influence the muscles, nerves, and heart. Cereals, whole grains, enriched refined grains, enriched bread, dairy products, liver, and leafy green vegetables. Liver, fish, chicken, lean red meat, nuts, whole grains, dried beans, and enriched refined grains.
Helps break down protein; helps maintain the health of red blood cells, the nervous system, and parts of the immune system. Helps the cells in the body make and maintain DNA; important for the production of red blood cells.
Leafy green vegetables, liver, citrus fruits, mushrooms, nuts, peas, dried beans, and wheat bread.
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