Sabtu, 20 April 2013

Protect Your Body from Free Radicals



Using Antioxidants to Help Slow Aging

A nationwide discussion is currently being held about how best to protect your body from free radical damage. It’s expected that as America gets older, more emphasis will be placed on means to slow down aging at all costs. What do free radicals have to do with getting older? And what exactly is a free radical?

Free radicals are waste products that result from the chemical reactions that take place in your body; they are molecules or molecular fragments that cause actual cellular damage to your body. Free radicals are dangerous – they increase the cellular deterioration and breakdown seen in aging; like wrinkles, diabetes, coronary artery disease, depression of the immune system and even cancer.(1)

It’s well-known that a lifestyle filled with drinking a lot of alcohol and smoking, as well as drug abuse, will cause huge increases in free radical production. But there is other behavior that contributes to increased free radical production, such as breathing in air pollution, working in a “sick” building or living on processed food, to name just a few. The body has to deal with those foreign substances, and free radicals often result.(1)

Ironically, the intense exercise routines that serious athletes go through can also cause free radical damage, causing them to also look a bit older than their true age; the observation has been pointed out for centuries that athletes and soldiers show their “wear and tear” early.(6)

Even though our bodies have protection from free radicals in the form of antioxidants scavengers, the protection is only so effective. Large increases in free radical production, even those caused by exercise, will no doubt overload the body’s natural defenses in time. Among other problems, these increases will cause a rise in levels of cortisol, a compound that will slow down fat loss from a diet, as well as other problems.(1) Excess cortisol is definitely bad for your New Year’s diet resolution.

What do you do? You Intervene.
If you are determined to live as long as possible with a certain quality of life, you must consider protecting yourself from these little free radical time bombs. Next I give you a basic guide to the essential antioxidants and vitamins you should take advantage of before it’s too late. These compounds are extremely effective antioxidants, but they also possess many other health benefits. Don’t worry; you’re not going to be overwhelmed with a large list of every supplement in existence. First, it’s not cost-effective and second, it can be counterproductive.

Basic vitamins — Vitamins C and E
Vitamin C is the antioxidant even your parents are familiar with. It slightly boosts your immune system, is a great antioxidant and is a requirement for several functions inside your body.(2) Vitamin C deficiency is very bad for the body and can even be deadly.
Vitamin E is an essential as well and it’s also good for your skin, hair, and your nails.(2) Stick with the recommendations on the bottle, taking too much vitamin E can be toxic.
A good quality multivitamin with minerals is also necessary to facilitate the thousands of chemical reactions going on in your body’s systems every day. Do not skimp on quality.

Pharmaceutical Grade Fish Oil
Dr. Barry Sears, the author of the popular book The Zone Diet, has a PhD in lipid science, which is the study of fats. Dr. Sears has been quoted as saying that pharmaceutical fish oil will change the way medicine is practiced in the future(9). Fish oil is one of the most effective supplements you can take, period. Not only is it good for your skin, your hair, and your nails, it also provides benefits for your heart, your lungs, and your brain.(9) Fish oil makes you healthier in general without a doubt, and some people believe it promotes fat loss and builds muscle, although these claims have not been proven.
Dr. Sears suggests using pharmaceutical fish oil only, and taking 3 to 5 g (g = grams = 3000 – 5000mg) per day, while a number of health magazines recommend 1 g per percent of body fat, per day.

Resveratrol
The compound is currently the hottest thing on the Internet since the blog. resveratrol is a chemical produced in plants and shows up in our lives mainly in the skin of grapes, made into wine. An interesting correlation was discovered years ago relating to the low instance of heart disease in French people and the amount of wine they consume per day, given the high fat levels in the French diet. This is called the French paradox(5).
Several years later it was discovered that it is resveratrol that provides the French heart protection from the sauces and butter so prevalent in French food. Not only the French, but many cultures that drink a lot of wine show the same low instance of heart disease in relation to the fact that the population drinks red wine on a regular basis.
While it is healthy to have one or two glasses of wine per night, the real benefits from resveratrol are found in supplements. And according to a lot of research, these benefits seem to be vast. Such as :
Reduction in the LDL and total cholesterol
Enhances immune function
Reduction in the oxidation of LDL cholesterol
Powerful anti-inflammatory properties
Decrease in fat production
Anticancer properties

All of these benefits of resveratrol have been clearly shown in the laboratory.(3,4,7) And that may be just breaking the surface.
On January 25, 2009, the CBS television show 60 minutes produced a segment on resveratrol that reveals just how powerful this chemical is. Scientists across the country now believe we may be able to slow down the genes that control the aging process using resveratrol. How it works is beyond the scope of this article but there are pharmaceutical drugs already under development that are derived from the compound.
Quality resveratrol supplements can be purchased online for as little as $15 per bottle whereas the highest quality goes for about 30. Optimal dosage levels have not been determined, it seems that 400 – 800mg before breakfast is being used safely, do your own homework before munching on these tablets like grapes.
This is the basic stack of antioxidants that should cover the known bases up to now and limit your oxidative stress and damage. Frequent tune-ups and careful use also required and always check with your doctor before taking anything new.
Just a short consumer warning: stay away from “free trials” of resveratrol unless you care to over-pay $80 to $100 per bottle of low dosage resveratrol. Checking the fine print you will see that you will be agreeing to a charge of this amount or more every month. (These companies give the diet supplement business a bad name) Good quality resveratrol can be found online priced at $25 to $40 and slightly higher for the absolute best. Welcome to the 21st century.
1. Zsolt Radak , Free Radicals in Exercise and Aging, Human Kinetics; 1 edition (August 7, 2000)
2. James F. Balch , The Super Anti-Oxidants: Why They Will Change the Face of Healthcare in the 21st Century, M. Evans and Company, Inc. (September 25, 1999)
3. Bharat B. Aggarwal, Resveratrol in Health and Disease (Oxidative Stress and Disease), CRC Press; 1 edition (November 1, 2005)
4. Philipp Saiko , Effects of Naturally Occurring Compounds on HumanCancer Cells: Anticancer Activity of Resveratrol, Piceatannol,Gallic Acid & their Analogs, VDM Verlag (August 6, 2008)
5. Lewis Perdue, French Paradox and Beyond: Living Longer With Wine and the Mediterranean Lifestyle, Renaissance Pub (August 1992)
6. McBride, J.M., Effect of resistance exercise on free radical production., Medicine & Science in Sports & Exercise, (1998)
7. Ferrero, M. E., Activity in vitro of Resveratrol on Granulocyte and Monocyte Adhesion to Endothelium.” (Amer I Clin Nutr 68, 1998).
8. Dr. Barry Sears, The Omega Rx Zone: The Miracle of the New High-Dose Fish Oil , Avon (December 28, 2004)

Antioxidants and Cancer Prevention

1.   What are antioxidants?
Antioxidants are substances that may protect cells from the damage caused by unstable molecules known as free radicals. Free radical damage may lead to cancer. Antioxidants interact with and stabilize free radicals and may prevent some of the damage free radicals might otherwise cause. Examples of antioxidants include beta-carotene, lycopene, vitamins C, E, and A, and other substances.
2.   Can antioxidants prevent cancer?
Considerable laboratory evidence from chemical, cell culture, and animal studies indicates that antioxidants may slow or possibly prevent the development of cancer. However, information from recent clinical trials is less clear. In recent years, large-scale, randomized clinical trials reached inconsistent conclusions.
3.   What was shown in previously published large-scale clinical trials?
Five large-scale clinical trials published in the 1990s reached differing conclusions about the effect of antioxidants on cancer. The studies examined the effect of beta-carotene and other antioxidants on cancer in different patient groups. However, beta-carotene appeared to have different effects depending upon the patient population. The conclusions of each study are summarized below.
o    The first large randomized trial on antioxidants and cancer risk was the Chinese Cancer Prevention Study, published in 1993. This trial investigated the effect of a combination of beta-carotene, vitamin E, and selenium on cancer in healthy Chinese men and women at high risk for gastric cancer. The study showed a combination of beta-carotene, vitamin E, and selenium significantly reduced incidence of both gastric cancer and cancer overall (1).
o    A 1994 cancer prevention study entitled the Alpha-Tocopherol (vitamin E)/ Beta-Carotene Cancer Prevention Study (ATBC) demonstrated that lung cancer rates of Finnish male smokers increased significantly with beta-carotene and were not affected by vitamin E (2).
o    Another 1994 study, the Beta-Carotene and Retinol (vitamin A) Efficacy Trial (CARET), also demonstrated a possible increase in lung cancer associated with antioxidants (3).
o    The 1996 Physicians’ Health Study I (PHS) found no change in cancer rates associated with beta-carotene and aspirin taken by U.S. male physicians (4).
o    The 1999 Women's Health Study (WHS) tested effects of vitamin E and beta-carotene in the prevention of cancer and cardiovascular disease among women age 45 years or older. Among apparently healthy women, there was no benefit or harm from beta-carotene supplementation. Investigation of the effect of vitamin E is ongoing (5).

4.   Are antioxidants under investigation in current large-scale clinical trials?
Three large-scale clinical trials continue to investigate the effect of antioxidants on cancer. The objective of each of these studies is described below. More information about clinical trials can be obtained using http://www.cancer.gov/clinicaltrials, http://www.clinicaltrials.gov, or the RePORT Expenditures and Results (RePORTER) query tool at http://projectreporter.nih.gov/reporter.cfm on the Internet.
o    The Women’s Health Study (WHS) is currently evaluating the effect of vitamin E in the primary prevention of cancer among U.S. female health professionals age 45 and older. The WHS is expected to conclude in August 2004.
o    The Selenium and Vitamin E Cancer Prevention Trial (SELECT) is taking place in the United States, Puerto Rico, and Canada. SELECT is trying to find out if taking selenium and/or vitamin E supplements can prevent prostate cancer in men age 50 or older. The SELECT trial is expected to stop recruiting patients in May 2006.
o    The Physicians' Health Study II (PHS II) is a follow up to the earlier clinical trial by the same name. The study is investigating the effects of vitamin E, C, and multivitamins on prostate cancer and total cancer incidence. The PHS II is expected to conclude in August 2007.

5.   Will the National Cancer Institute (NCI) continue to investigate the effect of beta-carotene on cancer?
Given the unexpected results of ATBC and CARET, and the finding of no effect of beta-carotene in the PHS and WHS, NCI will follow the people who participated in these studies and will examine the long-term health effects of beta-carotene supplements. Post-trial follow-up has already been funded by NCI for CARET, ATBC, the Chinese Cancer Prevention Study, and the two smaller trials of skin cancer and colon polyps. Post-trial follow-up results have been published for ATBC, and as of July 2004 are in press for CARET and are in progress for the Chinese Cancer Prevention Study.

6.   How might antioxidants prevent cancer?
Antioxidants neutralize free radicals as the natural by-product of normal cell processes. Free radicals are molecules with incomplete electron shells which make them more chemically reactive than those with complete electron shells. Exposure to various environmental factors, including tobacco smoke and radiation, can also lead to free radical formation. In humans, the most common form of free radicals is oxygen. When an oxygen molecule (O2) becomes electrically charged or “radicalized” it tries to steal electrons from other molecules, causing damage to the DNA and other molecules. Over time, such damage may become irreversible and lead to disease including cancer. Antioxidants are often described as “mopping up” free radicals, meaning they neutralize the electrical charge and prevent the free radical from taking electrons from other molecules.

7.   Which foods are rich in antioxidants?
Antioxidants are abundant in fruits and vegetables, as well as in other foods including nuts, grains, and some meats, poultry, and fish. The list below describes food sources of common antioxidants.
o    Beta-carotene is found in many foods that are orange in color, including sweet potatoes, carrots, cantaloupe, squash, apricots, pumpkin, and mangos. Some green, leafy vegetables, including collard greens, spinach, and kale, are also rich in beta-carotene.
o    Lutein, best known for its association with healthy eyes, is abundant in green, leafy vegetables such as collard greens, spinach, and kale.
o    Lycopene is a potent antioxidant found in tomatoes, watermelon, guava, papaya, apricots, pink grapefruit, blood oranges, and other foods. Estimates suggest 85 percent of American dietary intake of lycopene comes from tomatoes and tomato products.
o    Selenium is a mineral, not an antioxidant nutrient. However, it is a component of antioxidant enzymes. Plant foods like rice and wheat are the major dietary sources of selenium in most countries. The amount of selenium in soil, which varies by region, determines the amount of selenium in the foods grown in that soil. Animals that eat grains or plants grown in selenium-rich soil have higher levels of selenium in their muscle. In the United States, meats and bread are common sources of dietary selenium. Brazil nuts also contain large quantities of selenium.
o    Vitamin A is found in three main forms: retinol (Vitamin A1), 3,4-didehydroretinol (Vitamin A2), and 3-hydroxy-retinol (Vitamin A3). Foods rich in vitamin A include liver, sweet potatoes, carrots, milk, egg yolks, and mozzarella cheese.
o    Vitamin C is also called ascorbic acid, and can be found in high abundance in many fruits and vegetables and is also found in cereals, beef, poultry, and fish.
o    Vitamin E, also known as alpha-tocopherol, is found in almonds, in many oils including wheat germ, safflower, and corn oils, and is also found in mangos, nuts, broccoli, and other foods.

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