Re: Advice for personal protocol

from the article:

http://www.jacn.org/cgi/content/full/21/3/223
"Selenomethionine is the predominant form of selenium in most selenium enriched yeast products...

Based on animal data, selenium enriched yeast may not be the most effective source of selenium for reduction of cancer in humans. The efficacy of various selenocompounds using the mammary tumor model has been summarized in Table 4. Se-methylselenocysteine and selenobetaine are the most effective selenocompounds identified thus far against mammary tumorigenesis. Although selenobetaine is just as effective, Se-methylselenocysteine is considered to be the most interesting selenocompound because it is the predominant one present in selenium enriched plants such as garlic, broccoli florets and sprouts, onions and wild leeks (Table 2). Therefore, this selenocompound has received the most recent attention as possibly the useful one for cancer reduction

Se-methylselenocysteine is converted to methylselenol directly when cleaved by beta-lyase, and unlike selenomethionine it cannot be incorporated nonspecifically into proteins. Since these selenocompounds can be converted directly to methylselenol, this is presumably the reason they are more efficacious than other forms of selenium.

Even though selenomethionine is effective against mammary tumors, one disadvantage of it is that it can be directly incorporated into general proteins instead of compounds which most effectively reduce tumors. When this occurs, its efficacy for tumor reduction may be reduced. For example, when a low methionine diet is fed there is significant reduction in the protective effect of selenomethionine even though the tissue selenium was actually higher in animals as compared to those given an adequate amount of methionine [67]. When methionine is limiting, a greater percentage of selenomethionine is incorporated nonspecifically into body proteins in place of methionine because the methionine-tRNA cannot distinguish between methionine and selenomethionine. Feeding diets with selenomethionine to animals as the main selenium source will result in greater tissue accumulation of selenium than other forms of selenium [68,69]. It is not known whether this stored selenium can serve as a reserved pool of selenium, but the evidence indicates that it is metabolically active [70].

Using another model, selenium enriched broccoli florets [73–75], as well as enriched broccoli sprouts [51], have been shown to reduce colon tumors in rats. This is intriguing because colon cancer is the third most common newly diagnosed cancer in the United States [74]. However, different results were found with various forms of selenium. Selenium enriched broccoli was most effective, selenite and selenate were intermediate, but selenomethionine was ineffective in the reduction of aromatic amine-induced colon carcinogenesis [76,77]. Selenite, selenate and selenomethionine were more effective for induction of glutathione peroxidase activity than selenium enriched broccoli, but the enriched broccoli was more effective in the reduction of colon tumors, indicating that selenium bioavailability for enzyme induction is not correlated with its efficacy for cancer reduction [78]. Furthermore, the addition of selenite to regular broccoli florets or sprout powder was ineffective in the reduction of colon tumors [51], indicating that the plant converts the selenium to more effective forms for reduction of these tumors. These results emphasize the need to study the effects of selenium in food forms."

[personally, i am not one that likes to get in the habit of using laboratory made supps... like to look to food...]