The 400mcg mark is being researched and as shown by the NIM is felt to be safe, higher dosing. The first study is done with radiation treatment and shows benefit with the 400mcg. dose. The second study showed no additional benefit with this pathology, but also showed no detriment either over the 200mcg mark. Some scientists are calling for testing for higher dosing at 800mcg. as shown below as, again, the upper limit mark is 1/8th of where toxicity actually probably occurs. The last study looks at 400mcg selenium (combined treatment) with athletes in regards to ROS, with no benefit...as far as an antioxidant. While study results are mixed, there's no question amongst any standard in medicine this dose is safe, further still this is product to be used on workout days, 3-4 a week...also taken in to account. Average intake when used by the label would be 200mcg. Personally, I will use this everyday and can not wait to. Often results are mixed because the studies are using a few nutrients that should work individually and again aren't looking to provide substrates, push enzymatic action/pathways...the approach and the results would be radically different.
Again, I am excited to get these kinds of questions so I can elucidate all the thought and testing that has gone in to it! Thank you.
Clin Chim Acta. 2006 Nov;373(1-2):92-8. Epub 2006 May 19. Links
Enzymatic and non-enzymatic antioxidant status in stage (III) human oral squamous cell carcinoma and treated with radical radio therapy: influence of selenium supplementation.
Elango N, Samuel S, Chinnakkannu P.
Department of Medical Biochemistry, Dr. ALM Post Graduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai-600 113, India.
BACKGROUND: Oxidative stress is implicated in oral carcinogenesis and has been found to be aggravated during radiotherapy. A great deal of attention has been focused on the possible therapeutic implications of selenium as a potent antioxidant. We determined whether selenium supplementation to radiation treated oral cancer patients render improvement in the antioxidant status against oxidative stress. METHOD: Blood samples were collected from stage (III) oral cancer patients before initiating radiotherapy (Group B) (n=63) and this group is bifurcated into Group C-patients given radiotherapy alone (n=27) and Group D-patients given radiotherapy and supplemented with selenium (400 mug/day for 6 months) (n=36). Both Group C and D were followed up for 6 months. We evaluated the plasma selenium concentration, non-enzymatic system including GSH, vitamins E, C, A and ceruloplasmin and enzymatic antioxidant system including superoxide dismutase, catalase, glutathione peroxidase, glutathione reductase, glucose-6-phosphate dehydrogenase. RESULTS: The concentrations of selenium, all non-enzymatic antioxidants and the activities of enzymatic antioxidants were found to be lowered in oral cancer patients (Group B), compared to normal (Group A) (p<0.05). Similar decrease in the concentration of selenium and antioxidants status was observed in radiotherapy group (Group C) (p<0.05). On the contrary, selenium group (Group D) showed marked increase in the concentrations of selenium and antioxidant status at 6 months compared to radiation group (Group C) (p<0.05). CONCLUSION: The observed result represents the antioxidant property of selenium through the improvement of antioxidant defense system. Selenium supplementation could be of great interest in protecting cells against oxidative stress.
Nutr Cancer. 2008 Mar-Apr;60(2):155-63.Links
The nutritional prevention of cancer: 400 mcg per day selenium treatment.
Reid ME, Duffield-Lillico AJ, Slate E, Natarajan N, Turnbull B, Jacobs E, Combs GF Jr, Alberts DS, Clark LC, Marshall JR.
Roswell Park Cancer Institute, Elm & Carlton Streets, Buffalo, New York 14263, USA.
[email protected]
Nonexperimental studies suggest that individuals with higher selenium (Se) status are at decreased risk of cancer. The Nutritional Prevention of Cancer (NPC) study randomized 1,312 high-risk dermatology patients to 200-mcg/day of Se in selenized yeast or a matched placebo; selenium supplementation decreased the risk of lung, colon, prostate, and total cancers but increased the risk of nonmelanoma skin cancer. In this article, we report on a small substudy in Macon, GA, which began in 1989 and randomized 424 patients to 400-mcg/day of Se or to matched placebo. The subjects from both arms had similar baseline Se levels to those treated by 200 mcg, and those treated with 400-mcg attained plasma Se levels much higher than subjects treated with 200 mcg. The 200-mcg/day Se treatment decreased total cancer incidence by a statistically significant 25%; however, 400-mcg/day of Se had no effect on total cancer incidence.
Curr Opin Anaesthesiol. 2008 Apr;21(2):148-54. Links
Critically elucidating the role of selenium.
Vincent JL, Forceville X.
Department of Intensive Care, Erasme Hospital, Universit? Libre de Bruxelles, Brussels, Belgium.
[email protected]
PURPOSE OF REVIEW: To assess the current role of selenium supplementation in critically ill patients. RECENT FINDINGS: Studies consistently demonstrate decreased selenium concentration in plasma and whole blood in some critically ill patients, especially those with septic shock, and have suggested that persistent low concentrations may be associated with worse outcomes. However, clinical trials of selenium administration have not consistently or convincingly demonstrated improved outcomes. SUMMARY: Despite the low selenium content in the body (20-40 mg), selenoenzymes play an important role in antioxidant defense in humans. Selenium administration may be associated with improved outcomes, but further studies are needed to determine the precise mechanism of action. Studies are also needed to determine optimal dosing regimens, and to identify those patients in whom this approach is likely to be most effective. Currently, doses below the tolerable upper intake level (400 microg) may be used in supplementation. Higher doses (up to the level of no adverse effect, 800 microg) may be of interest and need to be studied further. The pro-oxidant effects of selenocompounds, especially sodium selenite, which vary depending on the compound, dose, and concentration, also need to be assessed further for their toxicity and potential therapeutic use in patients with septic shock.
Int J Sport Nutr Exerc Metab. 2005 Oct;15(5):480-92.Links
Exercise and mononuclear cell DNA damage: the effects of antioxidant supplementation.
Davison GW, Hughes CM, Bell RA.
School of Health Sciences, University of Ulster Jordanstown, Newtownabbey, Northern Ireland, UK.
The purpose of this investigation was to determine the effects of antioxidant supplementation on DNA damage following exercise. Fourteen subjects were randomly assigned to one of two groups and required to ingest either antioxidants (400 mg alpha-lipoic acid, 200 mg co-enzyme Q10, 12 mg manganese, 600 mg vitamin C, 800 mg N-acetyl cysteine, 400 microg selenium, and 400 IU alpha-tocopherol per day) or placebos for 7 d. Exercise increased DNA damage, PS, FRAP, and LDH (P < 0.05), but not selectively between groups. LDH and PS concentration decreased 1 h post-exercise (P < 0.05), while LH concentration decreased 1 h post-exercise in the antioxidant group only (P < 0.05). The antioxidant group had a higher concentration of LH (P < 0.05), perhaps due to a selective difference between groups post-exercise (P < 0.05). The main findings of this investigation demonstrate that exhaustive aerobic exercise induces DNA damage, while antioxidant supplementation does not protect against damage.
