Dr. Andrew Weil, M.D. author of Natural Health, Natural Medicine says, “High protein diets impose a considerable work load on the digestive system and may contribute to feelings of fatigue and lack of energy.” The problem with protein is that the liver has to work harder to detoxify the body from the nitrogen waste which results when it is metabolized. This compound called ure a has to eventually be eliminated from the body through the kidneys.

Most of us are routinely exposed to nicotine, toxins of various kinds and a whole host of synthetic drugs fro m ibuprofen to steroids. Most of us overeat the wrong things and pass up what’s really good for us. High fat, high sugar, high protein diets stress the liver. Overeating, especially overcooked, fatty foods puts added strain on the liver. In addition, lack of exercise has an indirect effect on the liver. When we don’t exercise, an excess of toxins can build up and has to be transformed by the liver.

Typically, when we are exposed to chemicals which can injure the liver, the amount of glutathione in the liver d e c reases. When this substance is reduced, the liver becomes susceptible to damage. The Silymarin content of Milk Thistle keeps concentrations of glutathione in the liver elevated by up to 35%.19 The ability of the liver to detoxify the system is largely dependent on the present of glutathione.

According to the American Liver Foundation, liver diseases are the fourth leading cause of death up to the age of 65. It is not commonly known that a significant incidence of liver disease exists in this country. In the past, liver disease was only associated with chronic alcoholics. Now, however, liver disease strikes obese people, social drinkers and people who eat poorly. Milk Thistle can help prevent the subtle kind of liver damage any of us may be susceptible to.

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Date: June 18, 2005 08:34 AM
Author: Darrell Miller (dm@vitanetonline.com)
Subject: Vision Quest - help fight eye problems.

Vision Quest by Phyllis D. Light, RH Energy Times, February 11, 2004

Since your eyes are in constant use every day, exposed to the damaging energy of sunlight and pollutants that waft through the air, these delicate orbs are often in danger of wearing out.

To keep this vital part of your anatomy functioning as you age, you have to feed and care for your eyes properly. Otherwise, you are in real danger of losing your vision and independence.

Your vision may be in danger. Experts estimate that 8 million Americans over the age of 55 are at serious risk of blindness linked to a condition called age-related macular degeneration (AMD). AMD can wipe out your central vision and is the primary cause of blindness in Western society.

While AMD causes no pain, it blurs the sharp, central vision necessary for driving, reading and other activities where you need to see either up close or straight ahead. During AMD, the macula, the part of the eye that allows you to pick out fine detail, is destroyed. The macula sits at the center of your retina, the nerve center at the back of your eye that senses light and sends optic signals to the brain.

Age is not the only risk factor for AMD. Scientists have isolated a genetic defect that can lead to some forms of macular degeneration (Nature Genetics 2001; 27:89-93). Smoking and excessive exposure to sunlight are other hazards best avoided if you want to save your sight.

In many cases, AMD progresses so slowly that victims of this condition don't even notice that their vision is deteriorating until much of it is irrevocably gone.

Dry and Wet AMD

Wet AMD occurs when blood vessels in back of the retina start to overgrow and leak blood. As this occurs, blood and other fluids push on the macula and quickly damage its sensitive nerve endings. When wet AMD occurs, you lose your central vision rapidly. If straight lines appear wavy to you, you may be suffering from wet AMD. If you notice this or other unusual vision changes, contact an eye care specialist as soon as possible. You need what is called a comprehensive dilated eye exam that can uncover signs of AMD.

Dry AMD strikes the eye when light-sensitive cells in the macula slowly deteriorate, gradually blurring central vision in the affected eye. As dry AMD progresses, a blurry spot in the center of your vision may appear. Eventually, as more of the macula becomes dysfunctional, the central vision in the eye can gradually disappear.

The most common sign of dry AMD is slightly blurry vision. This can make it hard to recognize faces and also make it harder to read without very bright light. Dry AMD generally attacks both eyes, but vision can be lost in one eye while the other eye stays normal. In the early stages of dry AMD, drusen, yellow deposits that gather under the retina, may form. Dry AMD progresses in three stages:

Vitamins and Minerals for AMD

Fortunately, scientists have found ways to combat AMD: An analysis of a study called the national Age-Related Eye Disease Study (AREDS) shows that more than 300,000 Americans could avoid losing their sight to AMD if they took daily supplements of antioxidant nutrients and zinc.

This conclusion, reached by scientists at Johns Hopkins' Wilmer Eye Institute, is based on research involving more than 4,500 adults suffering various stages of AMD. The study demonstrated that people who already had some AMD could lower their risk of the more advanced form of this condition by 25% when they took vitamin C, natural vitamin E and beta carotene along with zinc. Those suffering from advanced AMD lowered their chances of losing vision by about 19%. (Supplements did not affect the risk of cataracts or the chances of some vision loss for people in the early stages of AMD.)

" Without treatment to reduce their risk, we estimate that 1.3 million adults would develop the advanced stage of AMD," says Neil M. Bressler, MD, professor of ophthalmology at Johns Hopkins and author of the current study, published in Archives of Ophthalmology (11/03).

According to Dr. Bressler and the other researchers, people who now have intermediate AMD (some vision loss) in one eye have about a 1 in 16 chance of having their vision deteriorate until they have advanced AMD. They also calculate that about 1 in 4 of those with intermediate AMD in both eyes and 43% of those with advanced AMD in one eye will develop advanced AMD in five years without treatment.

In their view, older people at risk of AMD blindness should take daily supplements of 500 milligrams of vitamin C, 400 milligrams of natural vitamin E, 15 milligrams of beta carotene, 80 milligrams of zinc as zinc oxide and 2 milligrams of copper as cupric oxide. Evidence also exists that a diet which is high in fat can cause AMD to progress to an advanced stage. The exceptions: The healthy fats found in fish and nuts (Archives of Ophthalmology 2003; 121:1728-37).

Lutein Protection

Oddly enough, some of the same pigments that color vegetables and other foods also color your eyes. And scientists believe that those pigments, which are classified as carotenoids, help protect the eyes by helping them fight off the negative effects of caustic molecules called free radicals. Free radicals are formed when the energy from sunlight strikes the eyes and disrupts the composition of natural chemicals found there.

When scientists compared healthy eyes with eyes suffering from AMD, they found that AMD eyes contained lower levels of lutein and zeaxanthin, carotenoid pigments contained in egg yolk, spinach, broccoli and other dark green vegetables (Ophthalmology 2003; 109:1780). Furthermore, they found that levels of these chemicals generally decline as you grow older.

" This research is a major step toward large-scale clinical studies to prove the extent to which lutein and zeaxanthin protect against age-related macular degeneration," says Paul S. Bernstein, MD, PhD, at the University of Utah School of Medicine at Salt Lake. "We know that these carotenoids are specifically concentrated in the macula of the human eye."

Dr. Bernstein adds that, as you age, taking supplements containing lutein and other antioxidants may lower your AMD risk. In his investigation, people with AMD who did not take lutein had one-third less lutein in their eyes than older people whose vision was normal.

Avoiding Cataracts

Another eyesight hazard is cataracts, in which the eye's lens-the part that focuses incoming light onto the retina-becomes cloudy. Cataracts form when the proteins found in the normally clear lens become damaged; signs include progressively blurred vision (especially outdoors), focusing problems, seeing streaks of light from headlights and stoplights, and colors that look faded.

Cataract is the leading cause of blindness worldwide, according to the World Health Organization. One of every six Americans 40 and older suffers from some degree of cataract; it affects half of all Americans who reach age 80. Nuclear cataracts, the most common form of this disorder, develop in the center of the lens and tend to grow slowly. Cataracts may also develop at the back of the lens; this form is linked to eye trauma and long-term use of certain medications, including steroids.

Like AMD, cataracts become more common as people age. Up to 40% of individuals between the ages of 75 and 85 have them, compared with only 5% to 10% of those folks under the age of 65. And like AMD, sunlight exposure and smoking increase the risk of developing cataracts, as does the presence of diabetes.

Lutein and zeaxanthin, the carotenoids that are so plentiful in the macula, are also found in the lens (although in lower concentrations), leading many researchers to believe that these nutrients may help drop your risk of cataract development. Early studies indicate that an increased intake of lutein and zeaxanthin reduces one's chances of needing cataract surgery, the most common surgery in the United States (American Journal of Clinical Nutrition 1999; 70(4):509-16; 517-24).

Antioxidants and the Lens

Scientists believe that free-radical damage is a leading cause of cataracts, and so it isn't surprising that antioxidants have proved useful in preventing this problem.

Almost 500 women filled out diet questionnaires as part of a very large research effort called the Nurses' Health Study; those who had taken vitamin C supplements for 10 years or longer enjoyed the lowest rates of nuclear cataracts (Archives of Ophthalmology 2001; 119:1009-19).

So the answer to lowering your risk of eye problems is clear, whether you are already in your mature years or plan to be someday: Lead a healthy, eye-friendly lifestyle, eating a diet filled with colorful fruits and vegetables. Take frequent walks and jogs around the block.

And yes, when you kick back and take your just-as-frequent doses of antioxidant supplements, you're allowed to take your sunglasses off and see the world clearly.

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Vitanet ®

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Date: June 10, 2005 10:20 PM
Author: Darrell Miller (dm@vitanetonline.com)
Subject: Lose the Gluten - everyone who suffers from food allergies

Lose the Gluten by Phyllis D. Light, RH Energy Times, October 14, 2004

Are you a glutton for gluten, the sticky protein found in bagels and many other breads? Unfortunately, not everyone can enjoy the taste of fresh-baked bread because it contains this natural substance that can cause allergic reaction or intolerance in susceptible folks.

And while not everyone who suffers from food allergies or intolerances has a problem with gluten, other foods that can cause distress include items like watermelon, fish or even the benign-seeming peanut butter and jelly sandwich.

Still, with a little guidance, even if you have an allergy or two, you can enjoy meals and reduce food-related difficulties when you make food choices wisely.

According to the Food and Drug Administration, more than one in 50 adults and one in 12 children in the US suffer food allergies. But the problem may be even larger. Researchers believe even more of us have food allergies and don't know it: many food allergies and intolerances may be mistaken for irritable bowel syndrome or conditions like chronic fatigue syndrome.

Unhappy Digestion

The involvement of the immune system in an allergy represents the dividing line between intolerance and allergy. A food allergy strikes when the immune system attacks food ingredients as though they were threatening substances. Usually, proteins trigger these physiological alarms. The most common food allergens include wheat, soy, peanuts, shellfish, eggs, fish, tree nuts, milk and watermelon. Fortunately, many children who suffer allergies outgrow them as their bodies mature.

Signs of a food allergy may include a rash, hives, nausea, stomach pain, diarrhea, itchy skin, shortness of breath, chest pain, swelling of the airways and a condition called anaphylactic shock, a serious occurrence that can cut off breathing and requires immediate medical help.

If you believe you have a food allergy, see your health practitioner. If you have reasons to suspect an allergy to a particular food, avoid it altogether.

Intolerance Versus Allergy

Food intolerances are more common than allergies. They happen when food irritates the digestive system or offers substances that the digestive tract cannot break down. A food intolerance, however, does not provoke the immune system into an attack. The most common foods that cause intolerance are wheat, rye and barley; they all contain gluten.

Figuring out an intolerance generally requires adding and eliminating foods to gauge your response. Signs can include nausea, stomach pain, gas, cramps, bloating, vomiting, heartburn, diarrhea, headaches and irritability or nervousness. If you suspect you have a food intolerance, keep a food diary-recording what you eat and how you feel afterwards.

In addition, an elimination diet, wherein you avoid certain foods and track your responses, can help determine food intolerances. After you have dropped certain foods from your diet, reintroduce them, one at a time, until you eat a food that causes a return of your problems. These foods should then be permanently avoided.

Inflamed Intestines

Celiac sprue is a particularly severe inflammatory response to wheat or other grains containing gluten. According to the National Science Foundation, one in every 200 Americans suffers from this often misdiagnosed condition. That's more than a million of us!

If left untreated, celiac sprue can cause anemia, contribute to osteoporosis by limiting calcium absorption and increase the risk for intestinal cancer. Signs include headaches, weight loss, nutritional deficiencies, fatigue and neurological symptoms. The only treatment is to avoid all grains that contain gluten.

According to researchers in England, celiac sprue is often mistaken for chronic fatigue syndrome, type 1 diabetes or irritable bowel syndrome and can result in infertility (Med J Austral 2004 May 17; 180(10):524-6). Because sprue can confuse health practitioners, many people spend years trying to find an answer to their discomforts before finding that a gluten-free diet relieves their pain.

According to the Celiac Sprue Association, if you have gluten intolerance you should avoid durum wheat, semolina wheat, rye, kamut, spelt, barley, triticale and often oats. Some people find they can tolerate spelt, a distant cousin to wheat that's high in fiber and contains more protein (talk to your practitioner). Oats are generally well-tolerated by most people with gluten intolerance, but because oats are often processed on the same machinery as wheat, they may have traces of gluten. If you are gluten intolerant, you can still eat rice, corn, soy, potatoes, beans, sorghum, quinoa, millet, buckwheat, arrowroot and amaranth.

Problem Foods

Other food ingredients can trouble digestion. They include:

Fermented Foods

If you have what seem to be allergies and intolerances, fermented foods that contain beneficial bacteria (probiotics) can aid the functioning of your digestive tract. Yogurt, kefir, buttermilk and sauerkraut supply active bacterial cultures and are generally easy to tolerate because they are predigested. According to researchers at Tufts University, yogurt can improve your digestive health and soothe difficulties linked to allergies and intolerances (AJCN 2004 Aug; 80(2):245-56).

In addition, yogurt and other probiotic foods have been found to reduce the recurrence of irritable bowel flare-ups and may help reduce the risk of colon cancer. Yogurt improves gut microflora, increases bowel transit time and enhances immune response. Probiotics are also available as supplements.

Helpful Hints

If you have problems with certain foods or additives, becoming an amateur food detective can make meals more pleasant. Before eating a packaged food, always read the label; if you are unsure of the ingredients, contact the food manufacturer. But, in any uncertain situation, if you are in doubt of a food's ingredients, do without. Better to avoid food problems than realize too late that you've eaten a food that has upset your digestion.

Some people find their food intolerance comes and goes, often depending upon the amount eaten and how often a food is consumed. For example, some people with lactose intolerance find they can have a little milk in their coffee or on their breakfast cereal one day a week, but have problems if they drink milk on two consecutive days.

While deciphering which foods in your diet cause you problems can be time consuming, the reward for eliminating these nutrients, better digestion, is great. Don't give up! Persevere and, eventually your digestion will thank you.

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Vitanet ®

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Date: June 10, 2005 09:37 PM
Author: Darrell Miller (dm@vitanetonline.com)
Subject: Diabetes

Diabetes by , February 5, 2002

Lack of exercise and being overweight boosts your chances of developing diabetes. So, as America's epidemic of obesity grows, the number of people afflicted with the condition called type II diabetes is expected to soar. If you follow the typical US pattern of not getting enough exercise while indulging in a diet of too many calories from cookies, cakes, fast food and saturated fat as your waistline gradually expands, your chances of encountering this health menace grow every day. According to the most recent estimate by health researchers, "more than half of all US adults are considered overweight or obese"(JAMA, 10/27/99).

Those same researchers, who examined the health history and weights of more than 16,000 Americans, confirmed a fact well-understood by health practitioners who understand the chemistry of blood sugar: being overweight greatly increases your chances of not only diabetes but also high blood pressure, gall bladder disease, coronary heart disease, high cholesterol and arthritis. (If you suffer or think you suffer from diabetes, or any of these conditions, consult a knowledgeable health practitioner.)

Insulin Insurrection

While Type I diabetes is a relatively infrequent disease that often strikes kids, Type II diabetes is a much more widespread (and increasing) health problem experienced by 9 out of 10 adults with what is now called adult-onset diabetes.

The popular image of someone with diabetes is, ironically, often of someone who is suffering with Type I. In simplistic terms, Type I diabetes occurs when your pancreas stops producing insulin, a hormone-like substance that, among its several tasks, helps deliver sugar from the bloodstream into the body's cells. When your body is functioning normally, insulin helps steady blood sugar levels and keeps tissues fed with nutrients.

People with Type I diabetes often have to inject themselves with insulin. Otherwise, a lack of insulin causes dangerously increased blood sugar levels, cellular damage to blood vessels and nerves plus a high risk of heart attack, blindness, kidney failure and serious damage to your extremities that may, in the long-term, lead to amputation.

Insulin Resistance

On the other hand, someone beginning to suffer Type II diabetes usually has plenty of insulin being produced by the pancreas, but may be insulin resistant: for a variety of physiological reasons, the hormone is unable to do its job. That allows blood glucose to reach levels where it can wreak metabolic havoc.

When you gain weight, drastically increase the amount of your bodyfat and lead a sedentary, couch potato existence without engaging in very much exercise, you boost your risk of becoming insulin resistant. Consequently you also boost the chances of eventually suffering Type II diabetes.

However, a consistent exercise program (and losing weight) can alleviate or moderate some of the blood sugar problems brought on by diabetes or insulin resistance. When you exercise, your working muscles may take in more glucose from the bloodstream and stabilize your blood sugar level. That is one reason physical exercise helps to modify your body's response to blood sugar. (Of course, if you have diabetes or have not exercised in a long time, be sure to consult your health practitioner before engaging in strenuous physical activity.)

Supplemental Help

One of the most useful supplements employed to help control diabetes is chromium, a mineral that plays an integral role in the body's metabolism of sugar.

In the Natural Health Bible, Steven Bratman, MD, and David Kroll, PhD, discuss a study in China of 180 people with Type II diabetes. In that study, those who took chromium enjoyed better blood sugar levels than the people who took no supplements (Diabetes 46(11): 1786-1791, 1997). In addition, a double-blind study of chromium found that the supplement could reduce the necessary oral medication by more than half in many cases (Harefuah 125(5-6): 142-145, 1993). In this study, women seemed to benefit from chromium more than men.

Relief with Alpha Lipoic Acid

Alpha lipoic acid, an antioxidant nutrient, helps defend nerve cells against painful damage-a condition called neuropathy-that can result from diabetes. Consequently, in Germany, doctors have been prescribing lipoic acid to people with diabetes for more than two decades.

According to Dr. Bratman and Dr. Kroll, studies show that lipoic acid may be particularly helpful when taken with gamma-linolenic acid (GLA), a fatty acid found in evening primrose oil and borage oil. Studies of GLA have found that this fat can soothe numbness and pain and slow nerve injuries (Diabetes Care 16(1):8-15, 1993).

Taken together, GLA and lipoic acid may synergistically improve nerve function (Diabetologia 41(4): 390-399, 1998). Blood sugar control may also improve.

Healthy Mouth

Two signs that you may be suffering diabetes are excessive thirst and a dry mouth. This missing liquid, especially in the mouth when the flow of saliva slows, can lead to a lack of lactoferrin, a naturally-occurring protein that fights infection in the mouth by binding iron (Jrnl of Diab Comp 7, 57-62).

Lactoferrin's iron-binding ability destroys harmful micro-organisms like bacteria. In addition, lactoferrin stimulates the body's production of a substance called secretory IgA, which keeps disease-causing organisms out of the body and helps stabilize blood sugar (colostrum also produces this effect).

Spice Health

Fenugreek, a spice, has had long use as a medicine and food ingredient in the Middle East and Asia. And now modern science has begun to accumulate evidence supporting its traditional use: Several studies have shown that this seed can benefit blood sugar levels and keep blood cholesterol down.

In laboratory animals, researchers found that fenugreek kept blood sugar levels under control and also increased HDL (good cholesterol) while dropping triglycerides, blood fats that increase the risk of heart disease (Eur Jrnl Clin Nut 44 (1990):301-306).

Fortuitously, studies on people have supported fenugreek's benefits. In people with Type I diabetes, studies show that fasting blood sugar levels were reduced and glucose tolerance tests (measures of how well the body handles sugar) were closer to normal (Eur Jrnl Clin Nut 42 (1988):51-54). Bilberry for Eye Health

Retinopathy, eye damage resulting from diabetes, is a serious complication of this disease and can cause blindness. Bilberry, a botanical that has been used as a folk treatment for eye health for centuries, may be able to lower the risk of this kind of vision destruction.

Bilberry, a dark berry that grows in Europe, has been shown in a collection of laboratory tests to hold down blood sugar levels (Quart Jrnl Cr Drug Res 17(1979):139-196). Bilberry has traditionally been used to protect eyesight.

According to the Encyclopedia of Natural Medicine (Prima), natural substances called flavonoids, found in bilberry, "have been shown to increase intracellular vitamin C levels, decrease the leakiness and breakage of small blood vessels, prevent easy bruising and exert potent antioxidant effects."

Apparently, the body uses these flavonoids to protect the eyes' blood vessels and to keep the retina (central part of the eye crucial to preserving sight) functioning normally (Arch Med Int 37 (1985):29-35). Consequently, bilberry has been used by health practitioners in France to treat diabetic retinopathy ever since the 1940s.

Diabetes Research

As medical researchers look more closely into how insulin functions throughout the body, much more light will be thrown on how supplemental nutrients and your diet interact to promote the healthiest blood sugar levels.

But, today, what we already know about how the body functions can help you: a low-fat, high fiber diet, moderate, consistent exercise and healthy doses of insulin-friendly supplements may help keep your blood sugar under control.

And keep those pounds from accumulating around your waist. That way, you can keep from singing that nasty old, down and dirty, blood sugar, syncopated ragtime blues.

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Vitanet ®

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Date: June 09, 2005 09:27 AM
Author: Darrell Miller (dm@vitanetonline.com)
Subject: VITAMIN A and CAROTENOIDS - What are they good for?

Vitamins

In 1912, Casimir Funk coined the term 'vitamine' to refer to a 'vital factor' he proposed was an essential component present in foods. His conjecture dovetailed with other research, leading to the isolation in the 1930's and 40's of the compounds we now call vitamins.

Vitamins are chemical substances which play a variety of roles in the human body. They are core components of any nutritional supplementation program.

While many people are aware of vitamins as necessary substances for good nutrition, few have a grasp of the extraordinary complexity of the roles they play in our bodies. As you'll see below, vitamins are involved in trillions of biochemical interactions every minute to keep us alive and functioning. For example, B-vitamins are converted into coenzymes which are directly necessary for the production of ATP energy from food, a process that goes on continuously in every cell in the body and which in turn fuels myriad physiological events such as muscle contraction, brain activity or tissue repair.

Source Naturals offers a full line of vitamins in bioactive forms, allowing you to tailor a nutritional supplementation plan to your individual needs.

VITAMIN A and CAROTENOIDS

Vitamin A

Vitamin A is a generic term for a class of fat-soluble substances called retinoids, which can either be consumed preformed or synthesized by the liver from plant pigments called carotenoids (see 'Carotenoids', below). An essential nutrient, vitamin A is perhaps best known for its role in vision.

The outer segments of the rods, a type of light-sensitive cell in the retina of the eye, contain a pigment called rhodopsin (or 'visual purple') that mediates vision in dim light. Cone cells mediate color vision via three additional pigments. Both rods and cones are surrounded by pigmented epithelial cells that store vitamin A. Rhodopsin is formed from a protein called opsin and a vitamin A-dependent compound called 11-cis retinal. As light strikes the rods and cones it is absorbed by the pigment molecules, and retinal is split off from opsin. This chemical change allows an electrical impulse to be sent to the optic nerve and thus to the brain. The pigment must then be regenerated from opsin and retinal. Repeated small losses of retinal during this process require a constant replenishment of vitamin A to the eyes.

Vitamin A also plays an extremely important role in epithelial cell differentiation. Cell differentiation is the process by which a cell undergoes a change to a specialized cell type, allowing it to perform particular functions in the body. It is not yet understood precisely how vitamin A is involved in this process. One hypothesis is that it directly affects gene expression through its interaction with chromatin, a complex of DNA, RNA and protein in the cell nucleus. These interactions affect the process of transcription of DNA to messenger RNA, leading to synthesis of a specific group of cellular proteins.

Each one of us carries in our DNA a unique genetic blueprint. This genetic material is the same in every cell of our bodies. It is only because of this mysterious and magical process of differentiation that we have specialized cell types - and therefore eyes, ears, lungs and hearts.

Vitamin A is necessary, either directly or indirectly, for the healthy growth and functioning of many of our tissues and organ systems, including the eyes, the skin, the bones, the reproductive system, and the natural defenses. It is not yet known whether this requirement is due to the role of vitamin A in cell differentiation or whether there are other physiological processes for which vitamin A is essential.

Carotenoids

Vitamin A is related to a class of nutrients called carotenoids, including alpha and beta carotene, lycopene and lutein. Carotenoids are botanical pigments whose colors range from red to orange to yellow. Some carotenoids, particularly beta carotene, can be converted into vitamin A predominantly in the intestinal mucosa and to some extent in the liver. Carotenoids are completely non-toxic; their conversion into vitamin A is well-regulated by the body, making them extremely safe sources of this essential nutrient.

In addition to their role as safe sources of vitamin A, carotenoids are powerful nutrients in their own right. Their primary claim to fame is their powerful antioxidant action, particularly against singlet oxygen. Singlet oxygen is an 'excited' ion of oxygen which, while not technically a free radical, is nonetheless highly reactive. It causes 'oxidative' reactions which can impair or destroy membranes, enzymes and DNA. It can also lead to the formation of free radicals which can cause additional damage.

Certain carotenoids such as beta carotene, because of their chemical structure, can neutralize singlet oxygen by absorbing its extra energy and dissipating it throughout the carotenoid molecule, releasing the energy as heat and converting the singlet oxygen back to 'normal' oxygen. One molecule of beta carotene can quench up to 1000 molecules of singlet oxygen.

In addition to their role as singlet oxygen quenchers, carotenes provide antioxidant protection against free radicals as well. In nature, they protect plants from photo-oxidative reactions; in humans, certain carotenoids, notably beta carotene, may help protect the skin from such reactions. Other carotenoids may provide more localized protection to particular organs. Lutein and zeaxanthin, for example, are selectively concentrated in the retina of the eye. Along with vitamins C and E, carotenes are among the most important nutrient antioxidants in the human body.

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VitaNet ®
VitaNEt ® Staff

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