Tuesday, November 17, 2009

Selenium Supplements and High Cholesterol

I have a love-hate relationship with selenium. As you know if you read the research on supplements, some studies say that selenium has a strong anti-cancer effect. Other studies say that overall mortality goes UP when taking selenium supplements. Now, a new research study published in a peer-reviewed publication Nutrition indicates that selenium may be linked to higher cholesterol readings in those who supplement. This one may push it over the edge for me on taking selenium supplements . . .

Scientists at the University of Warwick Medical School said consuming too much selenium can have adverse effects. While it has strong antioxidant properties, and the above-mentioned perception that it can reduce cancer risks, there is now an apparently legitimate concern that higher quantities of selenium found in some supplements may be a bad thing.

The scientists reached this conclusion after examining the relationship between plasma selenium concentrations (levels of selenium in the blood) with blood lipids (fats in the blood). A cross-sectional study of the1042 participants in the 2000-2001 National Diet and Nutrition Survey (United Kingdom) revealed that among those with higher plasma selenium (more than 1.20 µmol/L) there was an increase in the average total cholesterol level of 8 per cent (0.39 mmol/L (i.e. 15.1 mg/dL). Researchers also found a 10 per cent increase in non-HDL cholesterol levels, which is the bad cholesterol most closely linked to heart disease.

Making the final step linking high selenium intake, supplementation, and high cholesterol, the scientists noted that among the participants, 48.2 per cent admitted they regularly took additional selenium in supplement form. Of course, you never know about these kinds of studies. This research team may have had an anti-supplement bias going into the study -- and perhaps they didn't explore what OTHER common indicators this population group may have had. Still, I think we all need to look at the available information on selenium before deciding if it is the right thing to do for our own personal situation.

Dave

2 comments:

LBJ11 said...

Was there any mention of the dosage level taken by the test subjects? I do take 200 mcg of this daily, half in multi-vitamin and half as supplement

Dave Jensen said...

Sorry, they didn't give guidelines on what is "normal" or "high" for supplementation. It was mentioned that this condition of overly high selenium can happen for reasons OTHER than supplementation. I think that 200 mcg is a very modest amount, and I wouldn't be concerned. It is the person who pops three or four times that amount, believing that it is a "cancer preventative" that should be worried about cholesterol levels.