Selenium. Too little, too much both not good. Use food. Whole wheat, fish, meat.

[JimJimJimJim]

Jim Marshall (not a doctor) said ...

We need selenium.

Dr. Susan J. Fairweather-Tait and her colleagues report in the first paper below:

• Too little is not good for avoiding prostate cancer, especially avoiding advanced prostate cancer.
  
• The complication is that too little and too much are not very far apart.
  
• Getting your selenium from supplements is not a good idea.
  
• Getting your selenium from foods is recommended.
  
• The story in UK and parts of Europe is more complicated because they now get less selenium from European wheat than they got 20 years ago from American wheat. (UK and European soils have less selenium than USA soils).
  

In the second paper extract below, Researcher at the University of Adelaide, Graham Lyons said...

• Probably the best sources of selenium are generally wheat products, particularly if it's whole wheat. Fish is a good source, meat is usually a pretty good source.
  
• Gluten intolerant vegetarians, he says, may find getting enough selenium a problem.
  
• In general, Australia's soils are probably a bit above the world's average.
  

... end Jim

Meta-Analysis Backs Selenium-Prostate Cancer Link

By Anne Harding

NEW YORK (Reuters Health) Jun 29 - Plasma selenium concentration within a "relatively narrow" range is associated with prostate cancer risk, according to a new systematic review and meta-analysis.

"Our dose-response meta-analysis showed a decreased risk of prostate cancer over a relatively small range of plasma/serum selenium concentrations, which suggests that there is an optimal range of selenium intake and status associated with prostate cancer risk reduction," Dr. Susan J. Fairweather-Tait of Norwich Medical School in Norfolk, UK, one of the study's authors, told Reuters Health.

Several studies have linked selenium status to prostate cancer risk, Dr. Fairweather-Tait and her colleagues explain, "but the dose response or beneficial range of intake or status associated with the risk reduction has not been established."

To investigate, the researchers looked at 12 studies involving 13,254 participants, including 5,007 with prostate cancer.

Their non-linear dose-response meta-analysis found risk of prostate cancer decreased with increases in plasma or serum selenium up to 170 ng/mL, the authors reported online May 30 in the American Journal of Clinical Nutrition.

Three "high-quality" studies, which looked at toenail selenium and prostate cancer risk, found risk was reduced with a concentration between 0.85 and 0.94 mcg/g.

"A plasma/serum selenium concentration of 135 ng/mL is associated with a 15% reduction in total prostate cancer risk and a 40% reduction in advanced prostate cancer risk," Dr. Fairweather-Tait told Reuters Health by email. "Further work is required to convert status measures to recommended intakes of selenium; that is the responsibility of risk assessors (e.g., the European Food Safety Authority), and risk managers who devise public health strategies."

Evidence to date suggests there is a U-shaped relationship between selenium status and cancer mortality, she added, "but further data are required on the high intake end of the curve."

Low selenium status is believed to be common in the UK and Europe, given the low concentration of the mineral in the soil. "Now that we can use European (soft) wheat for bread we no longer need to import wheat from Canada (which is very high in selenium), so one of our major dietary sources of selenium (wheat flour) is much reduced, and intakes of selenium have fallen over the past 20 years," Dr. Fairweather-Tait said.

She concluded: "Selenium appears to play a role in modifying the risk of prostate cancer initiation and progression, and when further research has been carried out to clarify dose-response relationships, there may be a therapeutic role for selenium, but for now we recommend that selenium (be) provided by foods rich in selenium, not supplements."

SOURCE: http://bit.ly/Lm4gkW

Am J Clin Nutr 2012.

Any highlighting (except the title) is not by the author, but by Jim Marshall. Jim is not a doctor.

In a recent Radio National interview, Researcher at the University of Adelaide, Graham Lyons said...

Well, as we always say, a nice varied diet is a very good start. Probably the best sources of selenium are generally wheat products, particularly if it's whole wheat. Fish is a good source, meat is usually a pretty good source. The best concentrated food source tends to be Brazil nuts, but they are highly variable so you wouldn't really know quite how much you were taking in. The ones we get here in Australia, you're not going to be taking in too much for a start. You wouldn't know whether you should be taking, say, five a day or a whole handful a day. So that's a good start. Things like vegetables often can have very low levels. So you find vegetarians who also may be, say, gluten intolerant so they can't be eating grain products, they could be at risk of too low selenium intakes.