from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun A salt, ester, or anion of selenic acid.
from The Century Dictionary.
- noun A compound of selenic acid with a base: as, sodium selenate.
from the GNU version of the Collaborative International Dictionary of English.
- noun (Chem.) A salt of selenic acid; -- formerly called also
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun chemistry any
saltor esterof selenic acid
from The American Heritage® Dictionary of the English Language, 4th Edition
In other words, selenate is the one form of Se to take if you're taking only one.
On the other hand, the similar extent to which low doses of either compound are retained suggests that once absorbed, both selenate and selenite can be utilized effectively for replenishing Se stores, in agreement with previous findings.
Only selenate or selenite can perform both sets of functions (anticancer activity and capacity for being stored), and of the two selenate is clearly superior because of its lower toxicity and lack of interference with metabolism of other nutrients.
The enhanced uptake of selenate over selenite is mediated by an active transport mechanism in the small intestine, presumably involving the same transporter protein that carries sulfate; sulfate is a close chemical cousin of selenate but not of selenite.
In a related experiment, both selenite and selenate-but not SeMet-significantly reduced the binding of the same carcinogen to DNA in rat colon.
To summarize, selenate has been shown to be an effective anticarcinogen while still retaining an ability to replenish Se stores.
Here the most widely available choices are sodium selenate and sodium selenite.
Although all forms of selenium described above are fairly well absorbed by the body, some studies show a slight edge to selenomethionine over selenocysteine, selenocysteine over sodium selenate, and sodium selenate over sodium selenite.
There are further problems associated with selenite, however: "antinutritive" activities not encountered with selenate.
There are clear differences between selenate and selenite as well, the most important of which is that selenite is much more toxic than selenate both in vivo and in vitro.