An rather interesting editorial was published in Annals of Internal Medicine; it's called Selenium and Diabetes: More Bad News for Supplements.
Let me please provide some introductory information regarding the primary source, The Annals of Internal Medicine
This information is provided by MedicineNet.com:
Definition of Annals of Internal Medicine
Annals of Internal Medicine, the: A medical journal especially concerned with information in the field of internal medicine (adult medicine). Designed to be read largely by internists, the Annals states it is "is the leading journal for studies in internal medicine." (Such claims aside, the Annals is without question one of the leading journals in medicine today. It is widely read and well respected. --Editor.)
Established in 1927 by the American College of Physicians (ACP), the Annals now serves as the official journal of the ACP and the American Society of Internal Medicine (ASIM).
According to the Annals, "The purpose of the journal - to promote excellence in the clinical practice of internal medicine - is supported by presentation of a wide variety of experimental and clinical subject matter in the Article, Brief Communication, Update, and Review formats. And to support the belief that physicians should also be well-informed citizens of both the medical community and society at large, Annals offers background and discussion of issues that influence both physicians and patients. This information is primarily carried in the Perspective, In the Balance, and Editorial formats. In addition, the journal presents personal narratives in the On Being a Doctor and the On Being a Patient formats that convey the feeling and the art of medicine."
"Over the years, both ACP (now ACP-ASIM) and Annals have grown. The College is the largest specialty organization in the country, continuing to work to enhance health care by fostering professionalism as prescribed in its mission statement. And the journal has expanded in circulation, improved in impact factor score, and adopted useful new features. A few of these features are peer review of articles (1960), the use of the structured abstract (1987), and the twice-monthly distribution of the journal (1988). As ACP-ASIM and Annals continue to grow, the central values of the art and science of medicine will continue to steer policy and practice."
Click here to read: Selenium and Diabetes: More Bad News for Supplements:
Here's an extract from the text:
EDITORIAL
Selenium and Diabetes: More Bad News for Supplements
Joachim Bleys, MD, MPH; Ana Navas-Acien, MD, PhD; and Eliseo Guallar, MD, DrPH
21 August 2007 | Volume 147 Issue 4
In this issue, Stranges and colleagues (1) report findings from the Nutritional Prevention of Cancer (NPC) trial that show an increased risk for diabetes among participants randomly assigned to receive supplements with 200 µg of selenium daily for 7.7 years compared with placebo. This effect was largely limited to participants in the top tertile of plasma selenium level at baseline (>121.6 ng/mL). In this group, the hazard ratio for incident diabetes in persons using selenium supplements compared with placebo was 2.70 (95% CI, 1.30 to 5.61). The NPC trial is the largest and longest available experimental study of selenium supplements compared with placebo. Although diabetes was not a primary end point of the trial and the investigators used self-report and medical records to assign the diagnosis, the results have credibility because of the randomized, double-blind design; the monitoring of baseline and follow-up plasma selenium levels; and other methodological strengths. The public health implications of these findings are substantial: More than 1% of the U.S. population take selenium supplements, and more than 35% take multivitamin and multimineral supplements (2) that often contain selenium.
...
Although obesity and lack of physical activity are the major factors responsible for the diabetes epidemic, environmental exposures may also be important. High selenium levels (12) or use of selenium supplements by persons with adequate selenium status (1) may contribute to this problem, although the extent of the role of these factors is unknown. Furthermore, the potential harmful effects of selenium supplementation in persons with high-normal selenium levels could extend beyond diabetes. A secondary analysis of the NPC trial identified some benefit of selenium supplementation for cancer prevention among participants with baseline plasma selenium levels less than 121.6 ng/mL but a possible small increase in total cancer risk among participants with higher levels (hazard ratio, 1.20 [CI, 0.77 to 1.86]) (18).
In the past decade, randomized, controlled clinical trials have shown that ß-carotene and vitamin E supplements, which were widely believed to be safe, increase mortality and morbidity (19, 20). No dietary supplement, including selenium, has proven useful so far for the prevention of cardiovascular disease or cancer in the general U.S. population. The balance of the potential benefits and harms of selenium supplementation depends on the dietary selenium intake in different countries. However, the U.S. public needs to know that most people in this country receive adequate selenium from their diet. By taking selenium supplements on top of an adequate dietary intake, people may increase their risk for diabetes.
Author and Article Information
From Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University Bloomberg School of Public Health, Baltimore, MD 21205.
Potential Financial Conflicts of Interest: None disclosed.
Requests for Single Reprints: Eliseo Guallar, MD, DrPH, Department of Epidemiology, Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University Bloomberg School of Public Health, 2024 East Monument Street, Room 2-639, Baltimore, MD 21205; e-mail, eguallar@jhsph.edu.
Current Author Addresses: Drs. Bleys and Guallar: Department of Epidemiology, Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins University Bloomberg School of Public Health, 2024 East Monument Street, Suite 2-600, Baltimore, MD 21205.
Dr. Navas-Acien: Department of Environmental Health Sciences, Johns Hopkins University Bloomberg School of Public Health, 615 North Wolfe Street, Room W7033B, Baltimore, MD 21205.
Here's something Annals released that's kind of cool for mainstream folks:
SUMMARIES FOR PATIENTS
Long-Term Use of Selenium Supplements and Risk for Type 2 Diabetes
21 August 2007 | Volume 147 Issue 4
Summaries for Patients are a service provided by Annals to help patients better understand the complicated and often mystifying language of modern medicine.
Summaries for Patients are presented for informational purposes only. These summaries are not a substitute for advice from your own medical provider. If you have questions about this material, or need medical advice about your own health or situation, please contact your physician. The summaries may be reproduced for not-for-profit educational purposes only. Any other uses must be approved by the American College of Physicians.
The full report is titled "Effects of Long-Term Selenium Supplementation on the Incidence of Type 2 Diabetes. A Randomized Trial." It is in the 21 August 2007 issue of Annals of Internal Medicine (volume 147). The authors are S. Stranges, J.R. Marshall, R. Natarajan, R.P. Donahue, M. Trevisan, G.F. Combs, F.P. Cappuccio, A. Ceriello, and M.E. Reid.
What is the problem and what is known about it so far?
Selenium is a mineral that is required in very low doses for the body to function normally. It is an antioxidant, meaning that it prevents damage to cells by oxygen.
Although most people get enough selenium in their diet, selenium is included in many multivitamins and is sold as a supplement itself. Many people take selenium supplements to stay healthy. Some research suggests that selenium supplements can improve the way the body handles sugar and might prevent some of the complications of diabetes. However, other research suggests that selenium supplementation has no effect on diabetes or health.
Why did the researchers do this particular study?
To see whether taking selenium supplements prevents diabetes.
Who was studied?
1, 202 people with skin cancer other than melanoma who were seen in dermatology clinics in areas of the United States where people tend to have low blood levels of selenium. None of the participants had diabetes.
How was the study done?
The researchers measured participants' blood selenium levels. They then randomly assigned the participants to take selenium supplements (200 micrograms) or placebo pills. They followed the participants over an average of 7 years to see who developed diabetes. They then compared the number of people with diabetes in the 2 groups.
What did the researchers find?
More people who took selenium developed diabetes compared with those who took placebo pills. The risk of developing diabetes seemed to be higher in people who had higher blood selenium levels at the start of the study.
What were the limitations of the study?
The researchers relied on participants' reports that they developed diabetes and did not confirm those reports with measures of blood sugar. The findings apply to the specific dose of selenium used in the study. Participants tended to be older and white, so the findings might not apply to younger people and those of other races.
What are the implications of the study?
Selenium supplements appear to increase the risk for diabetes. Although the findings need to be confirmed, long-term selenium supplementation should not be viewed as harmless and a possibly healthy way to prevent illness.
Thoughts or comments?
Take care.
