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Christmas Decorations, Colorectal Cancer and Vitamin D Jacob Schor, ND December 2, 2007 Subject: Review of several recent vitamin D and Cancer papers and links to past seasonally inspired newsletters A heated debate has been waged these past few months up in Fort Collins about Christmas decorations and whether the city should display them in public places. My local readers are well aware of the details, as they have been widely covered in our local media. The city council, an advisory panel and the public have argued at length about putting up traditional Christmas lights and trees versus a more secular display of white lights suggested by the panel. I caught the tail end of a news report a few weeks back, a sound-bite of an irate city constituent arguing that, “ Those white lights are pagan symbols. I want to see Christian symbols like colored lights and Christmas trees put up in my town.”
This thought made me chuckle in light of the hopefully inoffensive newsletters I have sent out at this season in past years. The holiday symbols thrust upon us at this time of year intrigue me and I pursue their origins with great curiosity. One newsletter I wrote reporting on betulinic acid and malignant melanoma digressed to describe claims that Santa is a modern representation of the traditions from reindeer peoples of northern Europe . Their shamans dressed in red suits celebrated the winter solstice spreading seasonal cheer with brightly colored hallucinogenic mushrooms. According to this theory, the image of a sleigh drawn by flying reindeers is not all that Christian; it stems from an ancient visions aided by the chemicals present in amanita mushrooms employed by these indigenous peoples. Then there was the newsletter on cranberries in which I digressed and mentioned the attitude of America 's early Christian settlers, the Pilgrims of the Massachusetts Colony toward Christmas celebrations. These early settlers with deeply held religious views banned any activity related to the holiday and enforced punishments on anyone caught celebrating. Times change and different people see the world quite differently. I am reminded of this by John Cannell and his December Vitamin D Newsletter. Dr. Cannell, as my readers may remember, is a major proponent of vitamin D supplementation and sends out regular literature updates related to this subject. In this current letter, he provides links to six separate news stories reporting on the findings of the same scientific paper. There is drastic contrast in how these headlines report the same story. The first headline run on Canadian Television on October 30 headlines: “Vitamin D cuts colon cancer death risk” [1]
The second story, which ran in Science Daily the next day, reads: “Study Finds No Connection Between Vitamin D And Overall Cancer Deaths” [2]
The next story, which also ran October 31, posted on medical-news.net, headlines: “Vitamin D protects against colorectal cancer” [3]
WebMD tells us that, “Vitamin D May Not Cut Cancer Deaths” [4]
Then the London times tells us that, “Scientists advise a Vitamin D downgrade as there is no real proof” [5] All of these articles appeared in response to a study written by Freedman and colleagues published October 30 in the Journal of the National Cancer Institute. If you care about stuff like this, and find these news reports confusing, you have little option but to go read the study yourself. Freedman DM, et al. Prospective Study of Serum Vitamin D and Cancer Mortality in the United States . J Natl Cancer Inst. 2007 Oct 30; That is if you have a paid subscription to the Journal of the National Cancer Institute. Those of you who don't can still read the abstract for FREE [6]
Freedman and his team tracked a large group of people, 16,818, starting in the late 1980s and early 1990s, and continuing until 2000. They measured Vitamin D levels of all the participants at the start of the study. After ten years, 536 of that initial group had died of cancer. The original vitamin D levels measured ten years back were not particularly good predictors of cancer death in general. Except that is for colorectal cancer. Having high levels of vitamin D appeared to be quite protective. “ Colorectal cancer mortality was inversely related to serum 25(OH)D level, with levels 80 nmol/L or higher associated with a 72% risk reduction” or put another way, those with the lowest level were four times more likely to die from colon cancer. Furthermore, 28 women in the study got breast cancer, 20 in the group with the lowest vitamin D level and only 8 in the highest. The breast cancer findings were not statistically significant. Keep in mind that having adequate vitamin D levels is rare. We make vitamin D when sunlight strikes our unprotected skin. One would think people living in Hawaii get enough sun exposure so they would all make plenty of vitamin D. Yet according to a study published in June 2007, only 51% of the adults living in Honolulu have adequate vitamin D. [7] If people in Hawaii can't be relied on to make enough vitamin D, it is an easy assumption that most of the people in the current Freedman study had low levels and that only a small percentage had adequate levels. It is little surprise that the study did not have the statistical strength to see or prove differences. Another large epidemiological study appeared the day after Freedman's did. It had very different findings. Abbas S, et al. Serum 25-hydroxyvitamin D and risk of postmenopausal breast cancer - results of a large case-control study. Carcinogenesis. 2007 Oct 31; Link [8] This study compared 1,394 women with breast cancer with a similar number of women without breast cancer. The women with breast cancer were three times more likely to have low vitamin D levels. Though these results are interesting, no PR was done and no news stories crossed my desk/screen about it. Both of these studies were epidemiological, not randomized controlled trials. One would think they carried equal weight. A randomized controlled trial published in June showed a 60% reduction in internal cancers in women in Nebraska taking even a modest 1,100 IU per day of vitamin D. [9]
When this study was published, as we wrote in our newsletter, the Canadian Cancer immediately advised all Canadians to take 1,000 IU per day and called for immediate large scale clinical trials. The American Cancer Society has not followed the Canadian lead. Those conspiracy inclined people watching this develop might think these curiously slanted news stories are the result of an organized PR campaign to belittle vitamin D effect. If that were so, one has to wonder who stands to profit from maintaining the status quo in regard to cancer incidence.
The American Cancer Society has taken a position that Americans should not take supplemental vitamin D until there are further randomized prospective control trials to prove Vitamin D does, as current researchers predict, cut cancer rates precipitously.
As Dr. Cannell writes, “That is, nothing should be done until more randomized controlled trials prove vitamin D prevents cancer, one randomized controlled trial is not enough; epidemiological studies are not enough, animal studies are not enough, multiple anti-cancer mechanisms of action are not enough?”
Cannell questions the American Cancer Society's,
As I have mentioned in the past, Dr. Cannell has strong beliefs.
Which brings us back to the well intentioned people in Fort Collins . Whether they have colored lights or white lights, Christmas tress or menorahs, a good percentage of them could still probably benefit from a little extra vitamin D. Other than that, I will not comment, except that with all that is going on in the world, well, no, better not to comment on this business…..
Test your vitamin D levels: The test used to assess vitamin D levels is called the 25(OH)D level. This is usually an expensive test to run. We are currently negotiating a special low price with our laboratory so we can test our patients at a reasonable cost. Tested levels of vitamin D is the accurate way to determine if needs to take vitamin D supplements. The Hawaii study tells us that getting plenty of sun exposure is no guarantee a person has enough vitamin D. We will send out details once the deal is final.
Links to newsletters with a seasonal theme:
John Cannell, MD's Website: http://www.vitamindcouncil.com/ Sign up to get his newsletters
Past newsletters on vitamin D: http://www.denvernaturopathic.com/news.html#vitaminD
References: [1] Vitamin D cuts colon cancer death risk Updated Tue. Oct. 30 2007 4:37 PM ET CTV.ca News Staff People with higher vitamin D levels in their blood are less likely to die of colorectal cancer, U.S. researchers said Tuesday. But the researchers also made the surprising discovery that the vitamin did not appear to affect the chances of dying from any other type of cancer. The study's results question the conclusions of several other recent studies that have found that vitamin D can lower the risk for many types of cancer. The Canadian Cancer Society was so impressed by the growing body of evidence about the health benefits of vitamin D that it recommended earlier this year that the entire adult population of Canada begin taking vitamin D supplements. The Society noted that Canadians are at particular risk of vitamin D deficiency since we typically don't produce enough vitamin D from sunlight. For this study, Dr. Michal Freedman, of the National Cancer Institute in Bethesda , Md. , and colleagues analyzed data from the third national Health and Nutrition Examination Survey. The researchers tracked 16,818 people who were part of the health survey between 1988 and 1994. The participants provided blood samples that the researchers used to determine the level of vitamin D in their blood. The researchers then followed the subjects through 2000. The study group was not asked about any vitamin D supplementation they might be taking. Among the group, 536 participants died of cancer during the study period. People with higher levels of vitamin D when they entered the study had an impressive 72 per cent reduced risk of dying from colorectal cancer, compared to those with the lowest levels of vitamin D, the researchers reported. But the researchers saw no link between vitamin D levels and the overall risk of dying from cancer, including from lung, prostate or breast cancer, non-Hodgkin lymphoma and leukemia. The results are published in the Journal of the National Cancer Institute. NIH experts Cindy Davis and Johanna Dwyer, in an editorial accompanying the study, noted that the six to 12-year period of the study may not have been long enough to demonstrate an effect of the vitamin on cancer deaths. This would be particularly true if vitamin D plays a role in preventing cancer in its earliest stages, as some suspect. As well, the commentary notes that the vitamin D blood levels were measured at only one time point and "may not have been representative of long-term chronic levels." They add: "These findings must be put into the context of total diet and lifestyle. There are many risk factors other than diet for colorectal cancer, and there are many possible dietary risk factors other than vitamin D that have been linked to cancer risk." They also caution that "the public should not, in a rush to judgment, assume that vitamin D is a magic bullet and consume high amounts of vitamin D. More definitive data on both benefits and potential adverse effects of high doses are urgently needed."
Web address: http://www.sciencedaily.com/releases/2007/10/ 071030160946.htm Study Finds No Connection Between Vitamin D And Overall Cancer Deaths ScienceDaily (Oct. 31, 2007) — No relationship was found between vitamin D levels and the overall risk of dying from cancer, according to a study published in the Journal of the National Cancer Institute. However, higher vitamin D levels were associated with a decreased risk of colorectal cancer death. Several epidemiological studies have supported the hypothesis that that vitamin D can reduce cancer mortality by decreasing cancer incidence or improving survival. Animal and cell studies suggest that vitamin D may reduce tumor growth and induce cancer cell death. Diet and exposure to sunlight are the major sources of vitamin D. D. Michal Freedman, Ph.D., of the National Cancer Institute in Bethesda , Md. , and colleagues analyzed data from the third national Health and Nutrition Examination Survey to examine the relationship between levels of circulating vitamin D in the blood and cancer mortality in a group of 16,818 participants aged 17 and older. After about a decade of follow-up, 536 participants had died of cancer. Cancer mortality was not related to the level of circulating vitamin D for the overall group, nor was it related when the researchers looked at the data by sex, race, or age. But higher levels of vitamin D (80 nmol/L or more) were associated with a 72 percent reduced risk of colorectal cancer mortality, compared with lower levels (less than 50 nmol/L). "To our knowledge, this study is the first to examine the relationship between measured serum vitamin D levels and cancer mortality for selected site and for all sites combined," the authors write. In an accompanying editorial, Cindy Davis, Ph.D., and Johanna Dwyer, D.Sc. of the National Institutes of Health in Bethesda , Md. , discuss the complicated relationship between nutrients, like vitamin D, and cancer. They suggest that not enough is known about the benefits and limitations of vitamin D to use it for the prevention of disease or death. "These findings must be put into the context of total diet and lifestyle. There are many risk factors other than diet for colorectal cancer, and there are many possible dietary risk factors other than vitamin D that have been linked to cancer risk," the editorialists write. Journal Article: Freedman DM, Looker AC, Chang S-C, Graubard BI. Prospective Study of Serum Vitamin D and Cancer Mortality in the United States . J Natl Cancer Inst 2007; 99:1594-1602 Editorial: Davis CD, Dwyer JT. The "Sunshine Vitamin": Benefits Beyond Bone" J Natl Cancer Inst 2007; 99:1563-1565 Adapted from materials provided by Journal of the National Cancer Institute.
Cancer Health CenterVitamin D May Not Cut Cancer Deaths Study Shows No Link Between Vitamin D Level and Cancer Deaths -- Except for Colorectal Cancer By
Miranda
Hitti Reviewed by Louise Chang, MD Oct. 30, 2007 -- Cancer researchers today reported that blood levels of vit amin D -- whether high or low -- may not help prevent adults from dying of cancer over a dozen years. But colorectal cancer may be the exception, according to the scientists, who included D. Michal Freedman, PhD, MPH, of the National Cancer Institute. Vitamin D has attracted attention from researchers for its possible anticancer effects. Freedman's team studied data on more than 16,800 people aged 17 and older who participated in U.S. health studies between 1988 and 1994. In those studies, participants got a blood test to measure their blood level of vitamin D. Freedman and colleagues followed the participants through 2000. During those 12 years, 536 participants died of cancer. Participants' vitamin D levels at the study's start didn't appear to affect cancer mortality in general, regardless of age, sex, race, or other factors. However, people with high levels of vitamin D at the study's start were 72% less likely than those with low levels of vitamin D to die of colorectal cancer. Death rates for the other cancers that were studied, including lung cancer, breast cancer, prostate cancer, other digestive cancers, non-Hodgkin's lymphoma, and leukemia, weren't linked to vitamin D blood levels. The study's limits include the fact that participants only had their vitamin D level checked once. So it's not clear if their vitamin D level rose or fell over the years. Freedman's team had lots of data including which participants smoked and exercised. But they can't rule out the possible influence of other factors. The study appears in next week's edition of the Journal of the National Cancer Institute . An editorial published with the study states that "the relationship between nutritional factors and colorectal as well as other cancers is complicated" and that the findings "must be put into the context of total diet and lifestyle." The editorial was written by experts including Johanna Dyer, DSc, RD, of the Office of Dietary Supplements at the National Institutes of Health (NIH).
[5] Vitamin D downgrade as scientists advise there is no real proof it fights cancer 30.10.07
The cancer-fighting abilities of the 'sunshine food' are being questioned Vitamin D, once heralded as a major weapon in the war on cancer, in fact does little to cut the risk, a study has discovered. The sunshine vitamin has been widely credited with warding off cancer, strengthening bones and cutting the risk of heart disease and diabetes. But a ten-year study of thousands of men and women has questioned its cancer-fighting properties. It was found that those with high levels were no less likely to die of the disease than others. The statistics for bowel cancer were the only ones to show a clear benefit from taking the vitamin. Cancer experts who carried out the U.S. government-funded research said not enough is known about the benefits and limitations to use it for the prevention or treatment of disease. They looked at how vitamin D affected the health of almost 17,000 men and women and started by measuring the amount in their blood. A decade later, 536 of the volunteers had died from cancers ranging from lung cancer to breast cancer. Analysis carried out at the National Cancer Institute in Maryland did not find a link between the risk of death from all types of cancer and vitamin D. Those with high levels of the vitamin were, however, 72 per cent less likely to die of bowel cancer which claims 16,000 lives a year in Britain . Only lung cancer kills more. It was recently estimated that almost 30,000 cases of breast and bowel cancer could be prevented each year if Britons spend more time in the sun. Although it is found in food, particularly oily fish such as salmon, mackerel and tuna, most of the vitamin D in our bodies is made when our skin is exposed to sunlight. Researchers from the Office of Dietary Supplements in the U.S. said: "Health professionals and the public should not assume that vitamin D is a magic bullet and consume high amounts of it. "More definitive data on both the benefits and potential adverse effects of high doses are urgently needed." In Britain , the Food Standards Agency says most of us should get all the vitamin D we need from a combination of a balanced diet and a little sunlight. It recommends that pregnant and breastfeeding women take a 0.01mg supplement each day. Ed Yong, of Cancer Research UK , said: "This is a large study, but it's only one piece of the jigsaw. It is still unclear how big a part vitamin D plays in the fight against cancer, or how much vitamin D you need for good health. "The best advice is to get a variety of different nutrients through a healthy, balanced diet, rather than relying on supplements."
[6] J Natl Cancer Inst. 2007 Nov 7;99(21):1594-602. Epub 2007 Oct 30. Prospective study of serum vitamin D and cancer mortality in the United States.Freedman DM, Looker AC, Chang SC, Graubard BI. Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, Department of Health and Human Services, Executive Plaza South Rm 7036, 6120 Executive Blvd, Bethesda, MD 20892-7238, USA. mf101e@nih.gov
BACKGROUND: Vitamin D has been hypothesized to reduce cancer mortality through its effects on incidence and/or survival. Epidemiologic studies of the association of 25-hydroxyvitamin D [25(OH)D] and the risk of cancer, however, have been largely limited to incident cancers at a few sites. METHODS: A total of 16,818 participants in the Third National Health and Nutrition Examination Survey who were 17 years or older at enrollment were followed from 1988-1994 through 2000. Levels of serum 25(OH)D were measured at baseline by radioimmunoassay. Cox proportional hazards regression models were used to examine the relationship between serum 25(OH)D levels and total cancer mortality (in the entire population or according to race/ethnicity, sex, age, and retinol status) and mortality from specific cancers. Because serum was collected in the south in cooler months and the north in warmer months, we examined associations by collection season. All statistical tests were two-sided. RESULTS: We identified 536 cancer deaths in 146,578 person-years. Total cancer mortality was unrelated to baseline vitamin D status in the entire population, men, women, non-Hispanic whites, non-Hispanic blacks, Mexican Americans, and in persons younger than 70 or 70 years or older. We found no interaction between vitamin D and season or vitamin D and serum retinol. Colorectal cancer mortality was inversely related to serum 25(OH)D level, with levels 80 nmol/L or higher associated with a 72% risk reduction (95% confidence interval = 32% to 89%) compared with lower than 50 nmol/L, P(trend) = .02. CONCLUSIONS: Our results do not support an association between 25(OH)D and total cancer mortality, although there was an inverse relationship between 25(OH)D levels and colorectal cancer mortality.
PMID: 17971526 [PubMed - indexed for MEDLINE]
[7] J Clin Endocrinol Metab. 2007 Jun;92(6):2130-5. Epub 2007 Apr 10. Low vitamin D status despite abundant sun exposure. Binkley N, Novotny R, Krueger D, Kawahara T, Daida YG, Lensmeyer G, Hollis BW, Drezner MK. University of Wisconsin Osteoporosis Research Program, Madison , WI 53705 , USA . nbinkley@wisc.edu CONTEXT: Lack of sun exposure is widely accepted as the primary cause of epidemic low vitamin D status worldwide. However, some individuals with seemingly adequate UV exposure have been reported to have low serum 25-hydroxyvitamin D [25(OH)D] concentration, results that might have been confounded by imprecision of the assays used. OBJECTIVE: The aim was to document the 25(OH)D status of healthy individuals with habitually high sun exposure. SETTING: This study was conducted in a convenience sample of adults in Honolulu , Hawaii (latitude 21 degrees ). PARTICIPANTS: The study population consisted of 93 adults (30 women and 63 men) with a mean (sem) age and body mass index of 24.0 yr (0.7) and 23.6 kg/m(2) (0.4), respectively. Their self-reported sun exposure was 28.9 (1.5) h/wk, yielding a calculated sun exposure index of 11.1 (0.7). MAIN OUTCOME MEASURES: Serum 25(OH)D concentration was measured using a precise HPLC assay. Low vitamin D status was defined as a circulating 25(OH)D concentration less than 30 ng/ml. RESULTS: Mean serum 25(OH)D concentration was 31.6 ng/ml. Using a cutpoint of 30 ng/ml, 51% of this population had low vitamin D status. The highest 25(OH)D concentration was 62 ng/ml. CONCLUSIONS: These data suggest that variable responsiveness to UVB radiation is evident among individuals, causing some to have low vitamin D status despite abundant sun exposure. In addition, because the maximal 25(OH)D concentration produced by natural UV exposure appears to be approximately 60 ng/ml, it seems prudent to use this value as an upper limit when prescribing vitamin D supplementation. PMID: 17426097 [PubMed - indexed for MEDLINE]
[8] Carcinogenesis. 2007 Oct 31 Serum 25-hydroxyvitamin D and risk of postmenopausal breast cancer - results of a large case-control study.Abbas S, Linseisen J, Slanger T, Kropp S, Mutschelknauss E, Flesch-Janys D, Chang-Claude J. Division of Cancer Epidemiology, German Cancer Research Center , Heidelberg , Germany .
Various studies suggest that vitamin D may reduce breast cancer risk. Most studies assessed the effects of dietary intake only, although endogenous production is an important source of vitamin D. Therefore, the measurement of serum 25-hydroxyvitamin D [25(OH)D] better indicates overall vitamin D status. To assess the association of 25(OH)D serum concentrations with postmenopausal breast cancer risk, we used a population-based case-control study in Germany , which recruited incident breast cancer patients aged 50-74 between 2002 and 2005. Information on sociodemographic and breast cancer risk factors was collected by personal interview. For this analysis, we included 1394 cases and 1365 controls, matched on year of birth and time of blood collection. Conditional logistic regression was used to calculate odds ratios for breast cancer adjusted for potential confounders. Serum 25(OH)D concentration was significantly inversely associated with postmenopausal breast cancer risk. Compared with the lowest category (< 30 nM), odds ratios and 95% confidence intervals [OR (95% CI)] for the higher categories of 25(OH)D (30-45, 45-60, 60-75, >/= 75 nM) were 0.57 (0.45-0.73), 0.49 (0.38-0.64), 0.43 (0.32-0.57) and 0.31 (0.24-0.42), respectively (p(trend) <0.0001). Analysis using fractional polynomials indicated a non-linear association. The association was stronger in women never using menopausal hormone therapy compared to past and current users (p(interaction) <0.0001). Our findings strongly suggest a protective effect for postmenopausal breast cancer through a better vitamin D supply as characterized by serum 25(OH)D measurement, with a stronger inverse association in women with low serum 25(OH)D concentrations (< 50 nM).
PMID: 17974532 [PubMed - as supplied by publisher]
[9] Am J Clin Nutr. 2007 Jun;85(6):1586-91. Vitamin D and calcium supplementation reduces cancer risk: results of a randomized trial. Lappe JM, Travers-Gustafson D, Davies KM, Recker RR, Heaney RP. Osteoporosis Research Center , Creighton University , Omaha , NE 68131 , USA . jmlappe@creighton.edu
BACKGROUND: Numerous observational studies have found supplemental calcium and vitamin D to be associated with reduced risk of common cancers. However, interventional studies to test this effect are lacking. OBJECTIVE: The purpose of this analysis was to determine the efficacy of calcium alone and calcium plus vitamin D in reducing incident cancer risk of all types. DESIGN: This was a 4-y, population-based, double-blind, randomized placebo-controlled trial. The primary outcome was fracture incidence, and the principal secondary outcome was cancer incidence. The subjects were 1179 community-dwelling women randomly selected from the population of healthy postmenopausal women aged >55 y in a 9-county rural area of Nebraska centered at latitude 41.4 degrees N. Subjects were randomly assigned to receive 1400-1500 mg supplemental calcium/d alone (Ca-only), supplemental calcium plus 1100 IU vitamin D3/d (Ca + D), or placebo. RESULTS: When analyzed by intention to treat, cancer incidence was lower in the Ca + D women than in the placebo control subjects (P < 0.03). With the use of logistic regression, the unadjusted relative risks (RR) of incident cancer in the Ca + D and Ca-only groups were 0.402 (P = 0.01) and 0.532 (P = 0.06), respectively. When analysis was confined to cancers diagnosed after the first 12 mo, RR for the Ca + D group fell to 0.232 (CI: 0.09, 0.60; P < 0.005) but did not change significantly for the Ca-only group. In multiple logistic regression models, both treatment and serum 25-hydroxyvitamin D concentrations were significant, independent predictors of cancer risk. CONCLUSIONS: Improving calcium and vitamin D nutritional status substantially reduces all-cancer risk in postmenopausal women. This trial was registered at clinicaltrials.gov as NCT00352170.
PMID: 17556697 [P ubMed - indexed for MEDLINE]
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