Beta-carotene risks still unproven!

A recent journal article pointed out the widely-reported danger of smokers using beta-carotene, a natural source (provitamin) of vitamin A, as part of their multivitamins. 1 In this meta-analysis (as in common in such analyses) the researchers have neglected to consider pre-existing dietary and serum levels of this nutrient, making their claim to control by placebo inadequate to properly isolate this variable. In fact, this failure to determine the effects of beta-carotene at a dose-dependent plasma level – and by neglecting to measure total beta-carotene intake along with the relevant synergistic antioxidants associated with it, as opposed to simply measuring supplemental intake - raises serious questions about the validity of these results. 2 There is also legitimate scientific debate over the use of trans versus cis forms of this provitamin that may affect the way it is used by our bodies in vivo that dispute whether all forms are equal, which most studies simply do not address (including this meta-analysis). 3 Regarding beta-carotene safety little has been satisfactorily resolved, and the negative studies have been vigorously disputed for these and other reasons. For example, researchers have previously noted in the Journal of the National Cancer Institute that beta-carotene has been shown to not affect the risk of oxidative DNA damage in male smokers, despite its reputation as an antioxidant. But neither did the provitamin A prove to cause oxidative DNA damage. 4 It has become apparent to numerous observers that simply measuring supplementation of beta-carotene is not a good predictor of serum levels or of risk, and that a low level of total antioxidant intake may be a more valid marker in this regard. In fact, the dietary level of several antioxidants has been shown to be an independent predictor of plasma beta-carotene, especially in moderate alcohol drinkers. A recent study reports, "This may explain, at least in part, the inverse relationship observed between plasma beta-carotene and risk of chronic diseases associated to high levels of oxidative stress (i.e., diabetes and CVD), as well as the failure of beta-carotene supplements alone in reducing such risk." 2 As the authors (Tanvetyanon, et al) of this current analysis have themselves noted, the Physicians Health Study compared the effects of taking 50 mg of supplemental beta-carotene (over 83,000 IU) every other day to a placebo in 22,071 US male physicians aged 40-84 and found no adverse health effects over a 12-year study period. 5 Likewise, the Women’s Health Study of 39,876 health professionals found no significant difference on lung cancer rates when looking at the effects of 50 mg of beta-carotene administered on alternate days over 2+ years plus a 4-year follow up period, using forms and dosing similar to the Physician’s Health Study to achieve very high serum levels of beta-carotene. 6 In a third study used in the current meta-analysis, The Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group (ATBC), an antioxidant study in Finland was halted early because of a widely reported small increase in cancer rates among male smokers taking beta-carotene that were only possibly linked to that nutrient. 7 Headlines associated this supplement with cancer risk. Despite objections that the study was flawed, beta-carotene use dropped. This study continues to be widely cited and believed, despite the researchers’ own statements that the results were most likely due to chance. A later analysis published in July 2004 took another look at that same Finnish smokers study’s data, but now taking into account total antioxidant intake, which should have cleared away some of the scientific controversy over beta-carotene safety. The smokers’ risk of getting lung cancer was inversely associated with total antioxidants in the diet, with more total antioxidants resulting in fewer cancers. 8 In this study a composite antioxidant index was generated for each of the 27,000 men over 14 years. The calculated amounts of carotenoids, flavonoids, vitamin E, selenium and Vitamin C were compared to actual lung cancer rates, with a clear result: a combination of antioxidants lowered lung cancer risk in male smokers. Properly reviewed, beta-carotene was not the culprit; low antioxidant status was the more relevant factor affecting cancer rates, and supplementation with a single antioxidant supplement simply failed to create enough improvement to avert deaths related to oxidative factors. Perhaps the supplementation with beta-carotene was simply a case of "too little, too late", rather than a root cause of a slightly higher lung cancer rate in those smokers. It is notable that Tanvetyanon et al included the ATBC study but failed to even reference the later Wright et al study that largely refuted the alleged harms of beta-carotene shown in ATBC, which were shown to be more likely due to low levels of total antioxidant intake than to excessive beta-carotene intake. This later review of ATBC should be a cautionary tale concerning the lack of proper controls in nutrient studies, especially as compounded by the use of meta-analysis, and should have alerted the current authors to that all-too-common mistake in nutrient study design. Indeed, another large study has noted that high carotenoid intake, confirmed by measures of plasma, was associated with lower mortality rates among the elderly over a ten year period. 9 This model measured results of consuming both supplements and foods, not solely supplement input, and when combined with plasma levels should therefore be regarded as a far more robust type of science for measuring vitamin effects than a meta-analysis of simply supplementation. As in the long-term Physicians Health Study, there was no observable risk of lung cancer noted in this report. The fourth study used in the current meta-analysis used very high doses of both beta-carotene (30 mg, equal to 50,000 IU) plus 25,000 IU of pre-formed vitamin A. 10 These amounts are extremely high; the Upper Limit for vitamin A is 10,000 IU, though there is no official Upper Limit for beta-carotene because of its historic safety record. The amounts of beta-carotene used in the eye vitamins were high only because the authors selected solely formulas designed for eye health that typically provide more beta-carotene than ordinary multivitamins. This distinction is not clear in their calling such formulas "multivitamins", because that name is typically given to full-spectrum formulas containing a full range of the essential vitamins with minerals, not system-specific formulas like those sold for eye health. Such formulas have proved to be beneficial in maintaining eye health and the combination of antioxidants have been stronger antioxidants than beta-carotene, which is potentially a pro-oxidant at times and could thus be used more safely – and effectively - in combination with other antioxidants. 11 That being said, eye formulas with more milligrams of lutein than beta-carotene are probably better formulated than ones with very high beta-carotene because of their competition for absorption. Most importantly, the authors have not shown why they assume that "multivitamin" use would be associated with the supposed risks of beta-carotene used singly, even if those risks for the solo provitamin are assumed to be true. Nor have they adequately demonstrated the alleged dangers of taking eye formula supplements, or even the danger of lung cancer rates increasing in those taking mixtures of beta-carotene combined with other antioxidant nutrients. In the case of multivitamins most studies have shown overwhelmingly positive effects, such as one report evidencing reduced infections in nursing homes with vitamins over placebo (73% vs. 43%). Intervention was with a multivitamin containing beta-carotene. Infection-related absenteeism was higher in the placebo group than in the treatment group (57% vs. 21%). Perhaps most importantly, 93% of participants with diabetes mellitus reported an infection versus only 17% of those receiving supplements. 12 These huge reductions in potentially serious infections among our elderly citizens should be measured against the relatively slight and mostly theoretical risk of increased lung cancer rates associated with beta-carotene supplementation. A study reported in the Journal of the National Cancer Institute looked at death rates in a population given multivitamins or other nutrients. 13 After supplements were given for 5.25 years in the general population trial of 30,000 people, significant reductions in total [relative risk (RR) = 0.91] and cancer (RR = 0.87) mortality were observed in subjects receiving beta-carotene, alpha-tocopherol, and selenium combined. The same researchers reported on a subgroup of 3,318 persons with esophageal Dysplasia (a precursor to esophageal cancer) that was given either a multiple vitamin-and-mineral supplement or a placebo for 6 years. In this portion of the trial, small reductions in total (RR 0.93) and cancer (RR = 0.96) mortality were observed but were not significant. In any case, no increase in cancer rates was noted in the group taking multivitamins; there was actually a possible small benefit in terms of reducing this risk. The participants getting the multivitamin took a daily beta-carotene capsule along with two multivitamin tablets. This was a group of subjects at high risk of getting throat cancer. 14-15 It is a leap of faith to assume that a single nutrient would have identical effects to a combination of nutrients without substantial supporting evidence, which is still lacking; confounded by conflicting evidence and multiplying variables in meta-analyses. Since nutrients are both synergistic and present in the diet, it is important to factor those known variables into a proper study design. All too often, researchers do not consider this fundamental difference between drug and nutrient research and unwittingly introduce extra variables that undermine their conclusions. 16

This current meta-analysis of 4 studies - only one of which unquestionably shows a slight increase in lung cancer risk but does not actually measure isolated beta-carotene risk; two others are well-designed and robust studies looking at serum levels of those taking a high dose of beta-carotene but show no increased risk in lung cancer rates, and the fourth has been largely shown to be moot by a later and more complete re-analysis of the data - does not support the hypothesis that beta-carotene increases rates of lung cancer and that multivitamins are therefore dangerous. Thus, there is no sound basis in the current review for suggesting that warning labels may be needed for multivitamins or eye health supplements containing beta-carotene along with other nutrients that have been shown in well-designed studies to help protect the eyesight – and independence - of our aging population. REFERENCES:

1. Tanvetyanon T, Bepler G. Beta-carotene in multivitamins and the possible risk of lung cancer among smokers versus former smokers: a meta-analysis and evaluation of national brands. Cancer. 2008 Jul 1;113(1):150-7. PMID: 18429004
2. Valtueña S, et al. The total antioxidant capacity of the diet is an independent predictor of plasma beta-carotene. Eur J Clin Nutr. 2007 Jan;61(1):69-76. Epub 2006 Jul 12. PMID: 16835597 [Supported by the European Community IST-2001–33204 'Healthy Market', the Italian Ministry of University and Research COFIN 2001 and the National Research Council CU01.00923.CT26 research projects.]
3. Andreas Schieber, Reinhold Carle. Occurrence of carotenoid cis-isomers in food: Technological, analytical, and nutritional implications. Trends in Food Science & Technology, Volume 16, Issue 9, September 2005, Pages 416-422
4. van Poppel G, Poulsen H, Loft S, Verhagen H. No influence of beta carotene on oxidative DNA damage in male smokers. J Natl Cancer Inst. 1995 Feb 15;87(4):310-1. PMID: 7707423
5. Hennekens CH, Buring JE, Manson JE, et al. Lack of effect of long-term supplementation with beta carotene on the incidence of malignant neoplasms and cardiovascular disease. N Engl J Med. 1996 May 2;334(18):1145-9. PMID: 8602179
6. Lee IM, Cook NR, Manson JE, Buring JE, Hennekens CH. Beta-carotene supplementation and incidence of cancer and cardiovascular disease: the Women's Health Study. J Natl Cancer Inst. 1999 Dec 15;91(24):2102-6. PMID: 10601381
7. The effect of vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. The Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group. N Engl J Med. 1994 Apr 14;330(15):1029-35. PMID: 8127329
8. Wright ME, et al. Development of a comprehensive dietary antioxidant index and application to lung cancer risk in a cohort of male smokers. Am J Epidemiol. 2004 Jul 1;160(1):68-76. PMID: 15229119
9. Buijsse B, et al. Plasma carotene and alpha-tocopherol in relation to 10-y all-cause and cause-specific mortality in European elderly: the Survey in Europe on Nutrition and the Elderly, a Concerted Action (SENECA). Am J Clin Nutr. 2005 Oct;82(4):879-86. PMID: 16210720
10. Omenn GS, Goodman GE, Thornquist MD, et al. Effects of a combination of beta carotene and vitamin A on lung cancer and cardiovascular disease. N Engl J Med. 1996;334:1150–1155.
11. Bartlett H, Eperjesi F. Age-related macular degeneration and nutritional supplementation: a review of randomised controlled trials. Ophthalmic Physiol Opt. 2003 Sep;23(5):383-99. Review. PMID: 12950886
12. Liu BA, et al. Effect of multivitamin and mineral supplementation on episodes of infection in nursing home residents: a randomized, placebo-controlled study. J Am Geriatr Soc. 2007 Jan;55(1):35-42. Erratum in: J Am Geriatr Soc. 2007 Mar;55(3):478. PMID: 17233683
13. Blot WI, Li IY, Taylor PR, et al. Nutrition intervention trials in Linxian, China: supplementation with specific vitamin/mineral combinations, cancer incidence, and disease-specific mortality in the general population. J Natl Cancer Inst 1993:8ı:1483-92
14. Li JY, Taylor PR, et al. Nutrition intervention trials in Linxian, China: multiple vitamin/mineral supplementation, cancer incidence, and disease-specific mortality among adults with esophageal dysplasia. J Natl Cancer Inst. 1993 Sep 15;85(18):1492-8. PMID: 8360932
15. Blot WI, et al. The Linxian trials: mortality rates by vitamin-mineral intervention group. Am J Clin Nutr. 1995 Dec;62(6 Suppl):1424S-1426S. PMID: 7495242
16. Levin, N. Land of Confusion: How Poor Science and Misleading Media Coverage Create Public Confusion About How Dietary Supplements Affect Health. J App Nutr, Vol 55, No. 1, 2005 8-15

Should cancer patients take vitamins?

Regarding the article “Should cancer survivors take supplements?” (14:34 ET, Thu 21 Feb 2008, http://features.us.reuters.com/wellbeing/news/FA7141DA-E0B3-11DC-91C7-1D7C8A14.html), I had written a rebuttal to a letter in CA: the Journal of the American Cancer Society, addressing these issues. (1) It is available on the journal’s web page, posted after editorial review. I cite numerous studies in which dietary supplements were used with cancer therapies, with no apparent problems. Additionally, since 40% of cancer patients actually die of malnutrition, please consider that it is wise to try to devise strategies to nourish the patients…they can’t live solely on chemotherapy and radiation, or surgery. Soon after, a review article addressed the same issue, reaching a similar conclusion: it is possible to mix dietary supplements with cancer therapies, in many cases improving results, though the timing is important. “CONCLUSION: None of the trials reported evidence of significant decreases in efficacy from antioxidant supplementation during chemotherapy. Many of the studies indicated that antioxidant supplementation resulted in either increased survival times, increased tumor responses, or both, as well as fewer toxicities than controls; however, lack of adequate statistical power was a consistent limitation.” (2) Science Daily reported that, “There is no evidence that antioxidant supplements interfere with the therapeutic effects of chemotherapy agents, according to a recent systematic review of the use of antioxidants during chemotherapy, available in the May, 2007 issue of the peer-reviewed journal Cancer Treatment Reviews. In fact, they may help increase survival rates, tumor response, and the patient’s ability to tolerate treatment.” (3) REFERENCES: 1. Cancer patients may very well tolerate the use of certain dietary supplements http://caonline.amcancersoc.org/cgi/eletters/55/5/319#176 2. Block KI, et al. Impact of antioxidant supplementation on chemotherapeutic efficacy: a systematic review of the evidence from randomized controlled trials. Cancer Treat Rev. 2007 Aug;33(5):407-18. Epub 2007 Mar 23. Review. PMID: 17367938 [PubMed - indexed for MEDLINE] 3. Antioxidants May Aid Chemotherapy Patients. ScienceDaily. Retrieved February 22, 2008, from http://www.sciencedaily.com/releases/2007/04/070426132954.htm Neil E. Levin, CCN, DANLA http://www.honestnutrition.com/

Selenium Safety

Selenium Safety By Neil E. Levin, CCN, DANLA 9/21/07 My comments refer to “Effects of selenium supplementation for cancer prevention in patients with carcinoma of the skin. A randomized controlled trial. Nutritional Prevention of Cancer Study Group” 1 Giving high doses of a single antioxidant is contrary to the realities biology and nutrition. It is unfortunate that synergistic nutrients are tested individually, like drugs. This is a pharmaceutical practice, not human nutrition, and also shouldn’t imply that comprehensive mixtures of nutrients (like a multivitamin) would have the same effects. Additionally, giving these doses to sick patient populations typically results in the authors’ cautions that their results are not applicable to the general population. Still, this disclaimer is routinely ignored in the significant portion of the media that tends to sensationalize the results in headlines or brief televised “health segments”. Antioxidants are synergistic and simply don’t work in isolation. In fact, high doses of single antioxidants have been shown to create imbalances, in vivo, and may even backfire. I consider these cases to be a fault of the study design and a lack of understanding of the scientific field, not a defect of the nutrient being studied. This report was primarily a study of patients with skin cancers, with a increase in self-reported Type 2 diabetes found during a “secondary analysis”. This means that strict elimination of various factors and strict screening of patients was not completed in relation to this unexpected outcome, and that researchers relied primarily on patients’ anecdoctal reports of being diagnosed with diabetes during the trial. This raises issues of undiagnosed cases of diabetes at the start of or during the trial, since even a few missed diagnoses could have (admittedly) reduced or eliminated the significance of the results. Admittedly, “detailed information on unmeasured risk factors at baseline, such as family history of diabetes, body fat distribution, and physical activity, are lacking.” This expands the variables far beyond those accounted for in the study design, which was really looking at cancer recurrences. (More on that later.) Other concerns with this report: • Only Caucasians were included in the patient population; almost all participants in the NPC trial were non-Hispanic white persons. Three-quarters of participants were men. • Patient compliance was also self-reported, limiting validity of the data. • Selenium is not an antioxidant commonly associated with glucose metabolism, so its selection is a bit odd, though in some past studies the mineral has given some indications that it may be useful. However, its close association with vitamin E, and the lack of data on coinciding use of that and other antioxidants, raises more questions than answers. Selenium was used in a study primarily looking at its effect on cancer, with good reason based on past science, and with self-reported diabetes only noticed as varying between the groups incidentally. • The “risk for type 2 diabetes did not differ between treatment groups within the top tertile of BMI” (Body Mass Index, indicating the most overweight people). This strongly indicates another possible variable and alternative explanation, reducing the validity of the implication that selenium alone was the cause of the increased diabetes self-reports. • A well known, name-brand selenium supplement was changed for a different one late in the study, without explanation. • High-selenium yeast products may not work the same as selenomethionine, the most popular type of selenium supplement currently sold. And yeast itself is considered to be a good dietary source of selenium and other nutrients, yet yeast was the placebo. • The population was consuming more than the Daily Value of selenium in their diet, so this was not a particularly selenium-deficient group before supplementation. And since they had all had previously diagnosed skin cancer, it appears that significant other factors, especially antioxidant synergies, were lacking in this patient group. The researchers admit that, “we cannot rule out the role of chance in our findings.” In other words, they admit that their report doesn’t really prove anything. In fact, in the original trial, the focus was on selenium and cancer. What were those results? Selenium alone so successfully reduced cancer incidences and cancer mortality that the study was halted early because a lack of selenium was so clearly associated with higher incidences and deaths from cancer. “Primarily because of the apparent reductions in total cancer mortality and total cancer incidence in the selenium group, the blinded phase of the trial was stopped early. No cases of selenium toxicity occurred. CONCLUSIONS: Selenium treatment did not protect against development of basal or squamous cell carcinomas of the skin. However, results from secondary end-point analyses support the hypothesis that supplemental selenium may reduce the incidence of, and mortality from, carcinomas of several sites.” 2, 12 Regarding the editorial about selenium and diabetes published in the same edition of the journal Annals of Internal Medicine, negative comments were made about the general safety of antioxidant supplements. 3 I dispute that “randomized, controlled clinical trials have shown that ß-carotene and vitamin E supplements, which were widely believed to be safe, increase mortality and morbidity”. The choices, increasing variables, and manipulation by statistical models in meta-analyses are often questionable. In this report, prediabetic symptoms were not even considered as a variable. Buijsse noted that high carotenoid intake, confirmed by measures of blood levels, was associated with lower mortality rates among the elderly over a ten-year period, countering the claim that ß-carotene dangers are proven. 5 The Miller meta-analysis 9, cited as proof of vitamin E’s dangers, was heavily criticized in published responses, and its conclusions were NOT replicated when the same data was re-analyzed (Hathcock) 7. It should therefore not be cited as proof of the vitamin’s danger. Another meta-analysis cited reported that antioxidant vitamins may increase death rates. But the authors did not determine a dose-dependent or cause-and-effect relationship between antioxidants and deaths (from all causes) of study participants. The researchers pooled 68 published trials, excluding 405 published studies with no deaths reported. Too wide a range of potencies (Vitamin A 1333 IU - 200,000 IU, vitamin E 10 IU to 1000 IU), and durations (28 days to 12 years) were lumped together. 4 The editorial statement, “No dietary supplement, including selenium, has proven useful so far for the prevention of cardiovascular disease or cancer in the general U.S. population,” is questionable. The Alpha-Tocopherol, Beta- Carotene Cancer Prevention (ATBC) Study published by the National Cancer Institute demonstrated a 32% reduction in prostate cancer incidence in response to daily alpha-tocopherol supplementation. 8, 10 The Women’s Health Study (JAMA) reported a significant 24% reduction in cardiovascular death with supplemental vitamin E. 11 The NIH reports, “Taking a daily supplement containing 200 mcg of selenium … significantly reduced the occurrence and death from total cancers. The incidence of prostate cancer, colorectal cancer, and lung cancer was notably lower in the group given selenium supplements.” 13 Yet the Annals editorial suggests lowering consumption below the Daily Value (70 mcg) used in multivitamins, far below the current official upper limit of 400 mcg. 13 On the contrary, the Lewin Group reports that the use of antioxidants could save the vision and independence of many senior citizens, saving billions of dollars in healthcare costs. 6 REFERENCES: 1. Stranges S, et al. Effects of long-term selenium supplementation on the incidence of type 2 diabetes: a randomized trial. Ann Intern Med. 2007 Aug 21;147(4):217-23. Epub 2007 Jul 9. Summary for patients in: Ann Intern Med. 2007 Aug 21;147(4):I14. PMID: 17620655 [PubMed - indexed for MEDLINE] 2. Clark LC, Combs GF Jr, Turnbull BW, Slate EH, Chalker DK, Chow J, et al. Effects of selenium supplementation for cancer prevention in patients with carcinoma of the skin. A randomized controlled trial. Nutritional Prevention of Cancer Study Group. JAMA. 1996;276:1957-63. 3. J. Bleys, A. Navas-Acien, and E. Guallar. Selenium and Diabetes: More Bad News for Supplements. Ann Intern Med, August 21, 2007; 147(4): 271 - 272. 4. Bjelakovic G, et.al. Mortality in Randomized Trials of Antioxidant Supplements for Primary and Secondary Prevention: Systematic Review and Meta-analysis. JAMA 2007. 297(8):842-857 5. Buijsse B, et al. Plasma carotene and alpha-tocopherol in relation to 10-y all-cause and cause-specific mortality in European elderly: The Survey in Europe on Nutrition and the Elderly, a Concerted Action (SENECA). Am J Clin Nutr 2005;82:879–886. 6. DaVanzo JE, et al. An Evidence-Based Study of the Role of Dietary Supplements in Helping Seniors Maintain their Independence. The Lewin Group Inc. January 20, 2006 7. Hathcock JN, et al. Vitamins E and C are safe across a broad range of intakes. Am J Clin Nutr. 2005 Apr;81(4):736-45. Review. PMID: 15817846 8. Weinstein SJ, et al. Serum alpha -Tocopherol and gamma-Tocopherol in Relation to Prostate Cancer Risk in a Prospective Study. J. Natl. Cancer Inst. 2005 97: 396-399; doi:10.1093/jnci/dji045 9. Edgar R. Miller, III, MD, PhD; et al. High-dose vitamin E supplementation may increase all-cause mortality, a dose response meta-analysis of randomized trials. Annals of Internal Medicine. 4 January 2005 | Volume 142 Issue 1 10. Alpha-Tocopherol, Beta-Carotene Cancer Prevention Study Group. The effect of vitamin E and beta-carotene on the incidence of lung cancer and other cancers in male smokers. N Engl J Med 1994;330:1029 –35. 11. Lee IM, et al. Vitamin E in the primary prevention of cardiovascular disease and cancer: the Women's Health Study: a randomized controlled trial. JAMA. 2005 Jul 6;294(1):56-65. PMID: 15998891 12. Combs GF Jr, Clark LC, Turnbull BW. Reduction of cancer risk with an oral supplement of selenium. Biomed Environ Sci. 1997 Sep;10(2-3):227-34. PMID: 9315315 13. Dietary Supplement Fact Sheet: Selenium. Office of Dietary Supplements • NIH Clinical Center • National Institutes of Health. http://ods.od.nih.gov/factsheets/selenium.asp

Am I biased?

A reader of my nutrition blog wondered if I may be biased. That's a fair question. Actually, I believe that everyone has to deal with the issue of bias, and the Scientific Method is supposed to help us all overcome these biases by focusing on valid, reproduceable data. Unfortunately, some of us seem to be trying harder than others to fairly represent unbiased data. For one example, my letter published by the cancer journal CA, the Journal of the American Cancer Society http://caonline.amcancersoc.org/cgi/eletters/55/5/319#176 rebutted an article positing that antioxidants should be avoided during cancer therapies. However, none of the references provided in that article showed any evidence of risk! In my rebuttal, I catalogued a number of studies that used nutrients with drugs or radiation therapies, which showed no harmful effects and in some cases even enhanced anticancer effects. I also pointed out the 40% of cancer patients who die of malnutrition while under their doctors' care, much of which may be preventable if physicians actually follow evidence-based medicine instead of clinging to conventional therapies and theories. Click on the title of this article to see the original report and my response. I think that you'll find that I presented relevant published scientific reports to counter a biased opinion that was not even supported by the author's references. How did that crappy opinion even get published in a peer-reviewed journal in the first place?