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The Ultimate Guide to FreeRadicals, Antioxidants,and CancerINSIDE THIS ISSUE1. Getting Started2. Where do free radicalscome from?3. Antioxidants To TheRescue4. Antioxidant SupplementsMay Preserve and ProlongYour Life5. SummaryGlobal IntegrativeMedicine AcademyGetting StartedBy JAMES MESCHINO D.C., M.S., R.O.H.PThestoryofvitaminandmineralsupplementation begins with an understandingof free radicals and antioxidants. It is widelyaccepted in the scientific community thatsubstances known as free radicals cause ent and progression of heart diseaseand stroke, Alzheimer’s disease and eneration of the eye, weakening of theimmune system, skin cancer, wrinkles and otherdegenerative conditions. In fact, free radicals arebelieved to play a role in more than sixty differenthealth conditions.
Page 2So what are free radicals? A free radical is a molecule that possesses an unpairedelectron, which must attempt to become whole and stable by stripping an electron froma neighboring molecule, as electrons spin around (orbit) the nucleus of an atom in pairs;one spinning clock-wise and the other spinning counter-clock wise. Thus, an atom ormolecule with an unpaired electron will use what even means necessary to acquire themissing electron to spin in the opposite direction around the nucleus, to pair itself up. Ifan atom or molecule is missing an electron (free radical state) it will strip an electronfrom a neighboring molecule, which was otherwise minding its own business. In turn, themolecule that has had an electron stripped away is now converted into a free radicaland must now steal an electron from another nearby molecule, which in turn, convertsthe nearby molecule into a free radical and so on. This chain reaction of free radicalpropagation is known to cause damage to many cellular structures, including the cellmembrane, enzymes, the DNA (genetic blueprints) and the mitochondria (energyfactory) within the cell, to name a few important ones. Studies show that free radicaldamage of this nature can cause alterations to the DNA of the cell that lead to cancer.This is how cigarette smoking causes lung cancer, as cigarette smoke is loaded with freeradicals that attack the DNA of lung cells creating cancerous mutations. Free radicaldamage to the cell also speeds up the aging process of the cell by damaging many ofthe structures, internal regulatory mechanisms, and the energy-producing machinery ofthe cell (mitochondria).
Page 3Where do free radicals come from?Well, cigarette smoke, as I mentioned, is loaded with free radicals, including second-handsmoke. This is why cigarette smoke has been shown to be responsible for approximately30% of all human cancers. However, there are many other sources of free radicals. It maysurprise you to learn that some of the oxygen we breathe in gets transformed into freeradicals during the course of normal metabolism. These oxygen radicals cause damageto body cells and tissues. If you have ever cut open an apple and left it exposed to the airfor a few minutes, you know that the exposed surface turns brown. This change in color iscaused by oxygen free radical attack. The same kind of reaction occurs in the body. Manyresearchers have shown that this type of oxidizing over a lifetime produces much of theaging of our tissues. In other words, to a certain degree we don’t age, we actually areslowly rotting just like the apple. Fortunately we can slow down the rate of rotting (oraging) by taking higher dose of antioxidants, as I will explain. However, the point is thatoxygen is a double-edged sword in that we need it to produce energy (without it we woulddie in three minutes or so), but at the same time, approximately 5% of the oxygen presentin our cells gets converted into very aggressive free radicals (oxygen free radicals). In fact,cancer expert, Dr. Bruce Ames, estimates that each cell in the body endures 10,000 freeradical hits per day just from oxygen free radicals. The cumulative effect of free radicalattack over our lifetime is responsible for a large degree of the aging process, the age-related weakening of our immune system and the age-related increase in cancerincidence and other degenerative diseases.
Page 4In addition to cigarette smoke and oxygen there are many other environmental and foodborne free radicals that can enter the body, which can greatly increase free radicaldamage to our bodies. Here are examples of some other dangerous, yet common, freeradicals:1.Alcohol – alcohol generates many free radicals and is responsible for approximately3% of all human cancers in North America2. Heterocyclic amines – these are formed when you char meat on a Bar BQ or eatblackened or Cajun-style proteins (meat or fish)3. Polycyclic aromatic hydrocarbons (PAH) – these are formed when the fat in meatdrips on to the Bar BQ coals and smoke rises into the meat or fowl. The smokecontains PAH, which then rises into the food on the grill. This is why smoked meat andfish are known to contain high levels of PAH, and regular consumption of these foodsare associated with increased incidence of stomach and esophageal cancers.4. Pesticides (e.g. DDT)5. Nitrosamines – these are formed when you consume foods (often cold cuts) thatcontain nitrate and nitrite salts. Once in the intestinal tract nitrates combine withamines (derivatives of protein digestion) to form nitrosamines, which are associatedwith cancer of the colon, rectum and other tissue sites.
Page 56. Ultra-violet light (from the sun and tanning beds) – UV-light penetrates the skinand converts oxygen within skin cells into free radicals by injecting them with anunpaired electron from the photon energy in UV-light waves. These free radicalsthen go on to cause skin accelerated skin aging and increase risk of skin cancer.UV-light can also reach deep into the dermal layers and cause cross-linking ofcollagen fibers, which results in skin wrinkling.7. X-Rays – radiation beams fired through the body initiate free radical formationin the our cells to a significant degree in much the same way that UV-lightinitiates free radicals in skin cells.8. Air Pollution – contains many free radicals of which nitrous oxide and polycyclicaromatic hydrocarbons are important ones.9. Occupational Free Radicals – these include substances such as carbontetrachloride, asbestos, vinyl chloride and heavy metals like mercury, cadmiumand lead.As you can see, your body comes into contact with a great number of free radicalinsults over your lifetime. Reducing your exposure to free radical as much is possible isan important way to reduce disease risk and slow aging, but it is also vital to optimizeyour antioxidant defenses, as antioxidants quench and neutralize free radicals andthereby minimize free radical damage to your body.
Page 6Antioxidants To The RescueThe unique feature about antioxidants is that they quench, intercept and neutralizefree radicals, converting them into stable, non-harmful substances and thus,prevent or halt free radical damage to your tissues. Antioxidants are able toneutralize free radicals because they have the ability to donate an electron orabsorb an electron from a free radical molecule, without being converted into a freeradical themselves. Fortunately, the body makes several antioxidant enzymes suchas glutathione peroxidase, catalase and superoxide dismutase to help reduce freeradical damage to the body. Without these enzymes to protect us from thedamaging effects of oxygen free radicals alone, we would all be dead within hours.The fact that our bodies synthesize these antioxidant enzymes is what enables us tolive in the earth’s atmosphere of 21% oxygen, and to use oxygen to power the energyproduction pathways in our cells. However, the antioxidant enzymes that the bodymakes require activation by certain minerals including manganese, magnesium,zinc, copper and selenium that we get from food and supplements. As well, ourbodies require additional antioxidant protection from nutritional antioxidants suchas vitamin A, vitamin C, vitamin E, Beta-carotene, lycopene, lutein and zeazantin, andbioflavonoids. Studies conducted over the past 25 years have provided evidencethat supplementing with many of these nutritional antioxidants, at levels beyondwhat food alone can provide, can have a significant impact on preventing manydegenerative diseases, and slow the aging process. This is why many expertsstrongly recommend that you take an antioxidant enriched, high potency, multivitamin and mineral each day.
Page 7In general, part of your life long wellness/anti-aging plan should include reducing yourexposure to unnecessary free radicals and maximizing your defenses against freeradical damage by consuming at least 5 servings per day of fruit and vegetables, andby acquiring additional antioxidant protection from an antioxidant-enriched, highpotency, multi-vitamin and mineral supplement each day.Antioxidant Supplements May Preserve and Prolong Your LifeIn general, part of your life long wellness/anti-aging plan should include reducing yourexposure to unnecessary free radicals and maximizing your defenses against freeradical damage by consuming at least 5 servings per day of fruit and vegetables, andby acquiring additional antioxidant protection from an antioxidant-enriched, highpotency, multi-vitamin and mineral supplement each day.Antioxidants Reduce Cancer RiskNumerous studies indicate that higher intakes of various antioxidants from food andsupplements help to reduce risk of many human cancers. Several prospective studiesthat began during the 1980’s, particularly ones done in Finland, and in Basel, Switzerland,provided some of the first compelling evidence that people who have higher intakes ofvitamin C, vitamin E, and beta-carotene, and who maintain appreciable blood levels ofthese nutrients through their lives, have a significantly lower risk of many cancers, thando individuals with lower intake and/or blood levels. Antioxidants, like vitamin C, betacarotene, vitamin E and others, quench free radicals that can cause cancerousmutations to the genetic material (DNA) of our cells.
Page 8Population studies show that the frequent ingestion of orange-yellow fruits andvegetables, and dark green vegetables, which provide many antioxidant vitamins, isassociated with reduced cancer risk. As reported by Ziegler, a number of studies haveshown that a high total carotenoid intake (e.g. beta-cartoene, lycopene lutein etc.) isassociated with a significant reduction in risk of cancers of the lung, stomach, breast,bladder and colon, as well as a several other tissue.As reported by Gladys Block, approximately 90 epidemiological studies haveexamined the role of vitamin C or vitamin C-rich foods in cancer prevention.According to these findings, evidence is strong that vitamin C may protect againstcancers of the esophagus, oral cavity, stomach, and pancreas and is substantial forcancers of the cervix, rectum, breast and lung. As for vitamin E, the associationbetween serum vitamin E levels and subsequent cancer risk has been examined in atleast 12 longitudinal studies. Overall, the studies showed, on average, a 3% lower bloodvitamin E levels among individuals who later developed cancer. In particular, vitamin Eappears to be protective against cancers of the stomach, pancreas, colon andrectum, and with selenium may reduce risk of reproductive organ cancers in women(e.g. breast cancer).Many of these preliminary studies were summarized in TheAmerican Journal of Clinical Nutrition supplement to volume 54, in December, 1991.Since these early reports many studies have been performed over the past 13 yearsthat have more closely examined the relationship between antioxidants and cancerprevention.
Page 9Colon CancerA number of antioxidants, including vitamin C, vitamin E, and selenium have beenshown to be important in the prevention of colon cancer.Selenium is a trace mineral that is known to prevent chemically-induced coloncancer in many animal studies. In one study with rats that were fed a known cancercausing chemical, the rats whose diets were supplemented with selenium had atumor yield of only 3%, whereas the rats who received no selenium supplementationhad a 29% tumor yield. Other animal studies have shown that seleniumsupplementation can reduce the incidence of intestinal tumors by 50% comparedwith rats given the cancer causing agent without selenium supplementation.Human observation studies are equally as impressive. For example, areas in NorthAmerica with low soil and crop selenium concentrations, show higher rates for colonand rectal cancers. Other human studies demonstrate that lower blood levels ofselenium are associated with an increased risk of developing colon cancer. In a studyof U.S. veterans, blood levels of selenium were measured in subjects with colorectalcancer and those free from colon cancer. The results demonstrated that subjects withblood selenium levels below 128 micrograms per liter were 4.2 times more likely tohave one or more cancerous polyps.
Page 10In a clinical trial using selenium to reduce risk of skin cancer 1,312 subjects were giveneither 200 micrograms of selenium or a placebo for almost five years. The subjectstaking the selenium experienced a 58% reduction in colon and rectal cancerscompared with subjects taking the placebo pill.More recently, a study by Dr. Mark Russo and associates at The University of NorthCarolina (Chapel Hill) showed further supported for the role of selenium in theprevention of colon and rectal cancers. In their study, patients who were referred for acolonoscopy assessment, also had blood tests performed. As reported by theseauthors, lower blood levels of selenium were associated with multiple cancerouslessons in the colon. The average blood level for patients with cancerous lesions was107 micrograms per liter compared to 120 micrograms per liter, for the cancer freesubjects.The authors conclude that this data support a protective effect of selenium againstcolon and rectal cancers after adjustments for possible confounding factors such assmoking, alcohol intake, use of dandruff shampoo (which contains selenium), vitaminE intake, vitamin C intake, iron intake, fat intake, and fiber intake. The researchers state,"Our results demonstrate that individuals with high plasma (blood) selenium levels areat a decreased risk for colorectal adenomas (cancerous lesions)". An increase of 30micrograms per liter in blood selenium level was associated with a 50% reduction inrisk of colon cancer lesions.
Page 11It is important to note, that other human studies by Dr. Willett, and Dr. Solonen , alsoreported, a 2 and 3 fold increased risk for colon and intestinal cancer respectively, inpatients presenting with low blood selenium levels when compared to patients withhigher blood levels.There are several ways that selenium is thought to reduce cancer risk. Selenium mayact as an antioxidant by increasing activity and levels of a powerful antioxidantenzyme called glutathione peroxidase.Glutathione peroxidase is considered a strong anticancer agent within the body.Selenium supplementation also decreases the formation of the cancer permissiveprostaglandin hormone known as prostaglandin series-2, which I will discuss in moredetail in the next section. Selenium metabolism itself may initiate changes that lead toprogrammed-cell death of cancer cells and pre-cancerous cells. Selenium is anessential nutrient for humans; it fulfills the physiological requirements for more than 13human enzymes and proteins.The average intake of selenium from food sources is shown to be between about 50micrograms daily. Is it adequate? This is not sufficiently adequate to maximize outcancer defenses according to the available research. The truth is that seleniumconsumed as a dietary supplement, beyond levels attainable from food, at 100-200micrograms (mcg) per day, has been shown to reduce the incidence of lung, colorectaland prostate cancer in humans.
Page 12As reported by B Combs and fellow researchers, selenium blood levels of approximately120 ng/ml (1.5 umol/ml) may be optimal for cancer prevention in general. The mostrecent estimates suggest that women require a minimum of 96 micrograms per dayand men require at least 120 micrograms per day to support plasma levels at 120 ug/ml(micrograms per milliliter). As for safety, toxicity of selenium begins at doses starting at1,000 micrograms per day, so 100-200 mcgs of selenium supplementation from multiplevitamin is extremely safe.Vitamin E has also been shown to reduce risk of colon cancer. On July 16, 1997, W.L.Stoneand A.M.Papas reviewed the world-wide scientific evidence related to vitamin E in theprevention of colon cancer (Journal of the National Cancer Institute).Previous studies dating back to 1982 demonstrated that 400 mg of vitamin E and 400mg of vitamin C, when taken daily, were able to dramatically reduce the formation ofcancer-causing agents (fecal mutagens) in the colon of test subjects.Like selenium, Vitamin E also inhibits the formation of a dangerous prostaglandinhormone known as Prostaglandin E2. High levels of Prostaglandin E2 are linked toincreased risk of colon cancer because it encourages the rapid division and growth oftumor cells and it helps cancer cells escape surveillance by the body's immune systemthat would otherwise kill these cancer cells in the normal course of events. Bysuppressing the formation of Prostaglandin E2, vitamin E helps prevent tumor cells fromgrowing and spreading and enables the immune system to function more effectively toidentify and destroy cancer cell that may emerge.
Page 13All of the animal studies reviewed by Dr. Prasad and fellow researchers, suggeststrongly that colon cancer is reduced when animals are supplemented with vitamin E,after being exposed to known cancer-causing agents.Animal and human studies are highly suggestive that vitamin E and selenium worksynergistically to reduce risk of colon cancer.More recently, the Iowa Women's Health Study demonstrated a very strong protectiveeffect for vitamin E in the prevention of colon cancer. The Iowa Women's Health Studywas a large-scale study of 35,000 women between 55 and 66 years of age who had noprevious history of cancer.This 4-year study provided convincing data that a high intake of vitamin E wasassociated with a reduced risk of colon cancer. Women in the top 20% level of vitamin Eintake had a 66% lower risk of developing colon cancer than women ingesting vitamin Ein the lowest 20% intake range.In almost all cases, the women with a high intake of vitamin E were taking supplementscontaining Vitamin E.Results from the Alpha-Tocopherol, Beta-Carotene, Cancer Prevention Study of 29,000male smokers from Finland also indicated that a daily supplement of 50 mg of vitaminE helped to prevent the subsequent development of colon and rectal cancer.
Page 14From a practical standpoint, I recommend that adults ingest 400 I.U. of vitamin E perday, from a high potency multi-vitamin and mineral, as a means to help preventcolon cancer, and other cancers. In fact, Vitamin E plays a role in the preventionof many degenerative diseases, as I will outline in this section. Vitamin E is fatsoluble, so you must take it with a meal that provides some fat in order for it to beabsorbed from your intestinal tract into the blood stream. The same is true forVitamin A, beta-carotene, lycopene, lutein, (other carotenoids) Vitamin D andVitamin K.Vitamin C, in a number of different types of studies, has consistently been shown to beassociated with a reduced risk of colon cancer. Vitamin C acts as an antioxidant in theintestinal tract and when supplemented, has been shown to decrease theconcentrations of cancer-causing chemicals in fecal matter. Vitamin C also blocks theformation of cancer-causing nitrosamines within the entire intestinal tract. Vitamin Csupplementation was also shown to reduce the recurrence of colon polyps by 35%compared to only 23% in the placebo group, in a 2.5- year study of polyp sufferers.Prostate CancerOne of the proposed mechanisms for the development of prostate cancer involvesfree radicals, as a number of studies suggest a link between free radicals (oxidativestress) and tumor development within the prostateIn several studies higher intakes and/or blood levels of the antioxidants vitamin E,selenium and lycopene have been associated with decreased prostate cancerincidence.
Page 15In the Alpha-Tocopherol,Beta-Carotene Cancer Prevention Study,long-termsupplementation with vitamin E was associated with a 32% decrease in the incidenceof prostate cancer compared with those not receiving vitamin E supplementation.Moreover, death from prostate cancer was 41% lower among men receiving thevitamin E supplement. The length of this supplementation study was 5-8 years and thedosage of vitamin E was 50 mg (alpha-tocopherol).Previous studies have observed that low blood levels of vitamin E in smokers areassociated with an increased risk of prostate cancer.Many researchers believe that antioxidant function is an important means to preventprostate cancer initiation and promotion. This contention is further supported by thework of Clark and fellow researchers, who demonstrated that supplementation withthe mineral selenium (mean time period 4.5 years) was associated with a 63% lowerincidence of prostate cancer. Blood levels of selenium have been reported to be low inpatients with prostate cancer. In preliminary reports, people with the lowest bloodlevels of selenium had between 3.8 and 5.8 times the risk of dying from prostate cancercompared with those who had the highest selenium levels.The Health Professionals Follow-up Study also supports the hypothesis that antioxidantfunction can prevent prostate cancer. In this study of nearly 48,000 subjects E.Giovannucci and fellow researchers reported that a significant decrease in risk ofdeveloping prostate cancer was associated with higher intake of lycopene.
Page 16It is interesting to note that the highest concentrations of lycopene occur in the testes,adrenals, and prostate gland. It is estimated that a minimum 4-6mg daily intake oflycopene is needed for prostate protection. An intake level of at least 6 mg per day ormore of lycopene was associated with approximately a 21% reduction in prostatecancer incidence in The Health Professionals Follow-up Study, compared with menconsuming less than 2.3 mg per day.Lycopene is the most effective quencher of singlet oxygen (a very aggressive beta-carotene-likecompounds) and is the primary carotenoid in the blood and various tissues, includingthe prostate gland.Taken together, the emerging research suggests that vitamin E, selenium andlycopene supplementation, at specific dosages, may significantly reduce the risk ofprostate cancer.Prostate cancer is the most common cancer in males in North America.Other nutritional factors and supplements may also help to prevent prostate cancerand are discussed in more detail in the prostate health section of the fellowshipprogram.
Page 17Breast CancerScientific investigation has revealed that vitamin E inhibits the growth of certainmalignant cells, including certain human prostate and breast cancer cell lines.In human populations, several epidemiologic (observational) and clinical interventionstudies have suggested that vitamin E supplementation can inhibit the developmentof certain cancers. In particular, the studies by Knekt, Malvy and the Alpha-Tocopheral,Beta-Carotene Cancer Prevention Study Group have all provided evidence thatvitamin E supplementation is associated with reduced risk of certain cancers, includingbreast cancer. For example, in the Nurses’ Health Study there was a 16% decreased riskof breast cancer in women within the top 20% of vitamin E intake compared to those inthe lowest 20% range.Women in the top 20% intake range were taking vitamin Esupplements in some form, to a large degree.Vitamin E supplementation is also associated with reducing the spread andprogression of breast cancer in women who have already had the disease. Accordingto the study by A. Fleischauer and fellow researchers, vitamin E supplementation inbreast cancer survivors is associated with 25-35% decrease in recurrence andmortality compared to non-users of vitamin E supplements. In fact, in women whohave had breast cancer, a cocktail of various antioxidants was shown to be helpful inthe study by K. Lockwood and fellow researchers.
Page 18These researchers conducted an 18-month study, involving 32 women with breastcancer. These women were put on a nutritional protocol consisting of high doseantioxidants and accessory nutrients. The women were between 32 and 81 years ofage and classified “high risk” because of tumor spread to the lymph nodes in the axilla(under the arm). The nutritional protocol, which was added to the normal surgical andtherapeutic treatments for breast cancer, consisted of a combination of the followingantioxidants. Vitamin C, 2,850 mg; vitamin E, 2500 IU; beta-carotene, 32.5 IU selenium,387mcg, plus secondary vitamins and minerals, essential fatty acids (1.2 gm gammalinolenic acid and 3.5 gm omega-3 fatty acids) and coenzyme Q10, (90-390 mg perday). Biochemical markers, clinical condition, tumor spread, quality of life parameters,and survival were followed during the 18-month trial. Compliance was excellent. Themain observations were: none of the patients died during the study period (theexpected number was four); none of the patients showed signs of further distantmetastases; quality of life was improved (no weight loss, reduced use of painkillers);and six patients showed apparent partial remission.This study indicates that various antioxidants and other nutrients can worksynergistically to help contain and prevent cancer to some degree.
Page 19Cervical CancerAntioxidants, such as vitamin E, beta-carotene and other carotenoids have beenshown to protect against cervical cancer in certain studies. In several, but not allstudies, elevated blood levels of folic acid, beta-carotene, lycopene, and vitamin Ehave been found to protect against cervical dysplasia (a precancerous condition ofthe cervix) In a recent study of 32 black women, by P. Kanetsky and fellow researchers,women with higher intake and blood levels of lycopene were one-third as likely to havecervical dysplasia as were women with the lowest one-third of lycopene blood levels.In addition, they were one-fourth as likely to develop the dysplasia if they had higherintake and blood levels of vitamin A, than were women with the lowest one-third ofvitamin A blood levels. Vitamin A is also an antioxidant vitamin and has other anticancer properties.Smoking is a known risk factor for the development of cervical dysplasia and betacarotene has been shown to be effective against smoking-related cervical dysplasiaand cervical cancer. This was documented in studies by HC de Vet and fellowresearchers, and W Jr. Winkelstein.In general, evidence suggests that low vitamin status of these antioxidants, folic acid(a B-vitamin), cigarette smoking and human papillomavirus infection combine tocontribute to the risk and progression of cervical dysplasia.
Page 20In a study of patients with mild or moderate cervical dysplasia, 30 patients weretreated with 30mg (50,000 I.U.) of beta-carotene orally for up to six months. More than70 percent of patients showed reversal of their condition by six months. However, onlythree months were required to realize optimal reversal of this condition, according tobiopsy studies of shed cervical cells.At this time there is sufficient evidence to suggest that nutrition and antioxidantsupplementation play a vital role in the prevention of cervical dysplasia and, in somecases, can reverse this condition in its early and moderate stages.Stomach CancerStomach cancer and colon cancer have been shown to susceptible to the influence ofa carcinogen known as nitrosamines. Nitrosamines represent an important group ofenvironmental carcinogens. On average, individuals consume approximately 74 mgper day of nitrates in North America. Processed meats that are treated are preservedwith nitrate and nitrite salts are a major source of these carcinogens. Many alcoholicbeverages contain nitrates, and soils treated with nitrogen fertilizers give rise to manyplant foods that now contain more nitrates than was the case before the use ofnitrogen fertilizers.
Page 21Thus, all of us are exposed to some background levels of nitrates entering the body.Within the stomach and intestinal tract nitrates can combine with protein (aminoacids) to form cancer-causing nitrosamines. Both vitamin C and vitamin E have beenshown to block the formation of nitrosamines when taken as supplements with, orshortly after, a meal containing nitrates and protein. For optimal protection, taking 500mg of vitamin C, twice per day has been shown to block as much as 85-100% ofnitrosamines formation under conditions of a high nitrate intake. A number of differenttypes of studies have consistently shown a strong protective effect of vitamin Cagainst stomach and colon cancer. The same is true regarding vitamin E. For vitamin E,a daily dosage of 400 IU can help block the formation of nitrosamines.
Page 22References: Antioxidants And CancerCancer In General:Ames Bruce N, et al. Oxidants, Antioxidants, and the Degenerative Diseases of Aging; Proceedings of theNational Academy of Science 1993 Sep;90:7915-22Block G. Vitamin C and cancer prevention: the epidemiologic evidence. Am J Clin Nutr. 1991;53(1):270-282Block G, et al. Fruits, Vegetables and Cancer Prevention: A Review of the Epidemiologic Evidence; Nutritionand Cancer 1992;187:1029Gutteridge John M. Antioxidants, Nutritional Supplements, and Life
health conditions. Getting Started By JAMES MESCHINO D.C., M.S., R.O.H.P Global Integrative Medicine Academy The Ultimate Guide to Free Radicals, Antioxidants, and Cancer. Page 2 So what are free radicals? A free radical is a molecule that possesses an unpaired electron, which must attemp
