Life Extension Magazine®

Getting What You Pay For

Ensuring quality control, safe selenium doses and more.

Scientifically reviewed by: Dr. Gary Gonzalez, MD, in October 2024. Written by: Life Extension Editorial Staff.

Q: I am skeptical about the amount of nutrients/ingredients that supplements contain. Recently the media have made evident that nutrients, which have been found to improve certain conditions, are not always present in the amounts that supplement labels claim. How can The Foundation ensure that it offers high quality supplements, and that listed amounts are actually supplied?

A: Your concern about bogus supplements is justified. An increase in consumer use of supplements has spawned unscrupulous companies who try to cash in on this huge market. As a result, some supplements have zero efficacy because what’s listed on the bottle is not what’s contained in the product.

Over 20 years ago, the Foundation began publishing a newsletter that contained educational information on nutrients and natural therapies that could help prevent disease, improve the quality of life and extend life span. At the time, the Foundation was not involved in the supplement industry. Inevitably, the Foundation soon found that what was available on the market was not the same as the quality of supplements used in scientific studies. That is why the Foundation began to produce supplements, and has access to a state of the art laboratory where chemists conduct innovative assays on its products. The Foundation has gained such a solid reputation for its quality control standards that in April of 1999 it was asked to analyze seven different brands of SAMe by a national news magazine. To ensure quality and inform consumers, a Quality Control Assay Report is available to members on any supplement upon request.

Q: In reviewing The Foundation's suggested supplement program, namely Life Extension Mix, Life Extension Booster and Chronoforte, I became concerned about the total amount of selenium in the combined package. Why does The Foundation believe that such quantities of selenium are safe, i.e. 500 mcg? For the moment, the latter issue has kept me from taking the Booster and Chronoforte. Could you please elaborate on the reasons behind your recommendation?:

A: The Life Extension Foundation has designed protocols that incorporate the best-documented disease-preventing nutrients and hormones. Selenium is an essential cofactor of glutathione peroxidase and is an important antioxidant. It is involved with iodine metabolism, pancreatic function, DNA repair, immunity and detoxification of heavy metals. The most recent studies demonstrate that selenium improves cardiac function and significantly improves cardiac functional recovery and decreases postischemic myocardial injury.

According to the Department of Agricultural Chemistry, Oregon State University’s study on the “Metabolism of subtonic levels of selenium in animals and humans” by Ann Clin, March-April 1996, “Low adverse effect level of dietary (mean LOAEL) selenium was calculated to be about 1540 +/- 653 micrograms per day (or 28 micrograms/kg body weight) and the maximum safe dietary (mean NOAEL) selenium was calculated to be 819 +/- 126 micrograms per day (or 15 micrograms/kg body weight).” For the average person, this study indicates that around 1000mcg of selenium a day is safe. Therefore, the combined amount of 500 mcg of selenium should pose no problem for you.

Q: I am writing an educational monograph on CLA and I ran into a problem that I can’t figure out. I have come across correspondence from your organization that explained the relationship between linoleic acid and CLA. It stated that standard linoleic acid is also called cis 9-, cis 12-octadecadienoic acid, where the two double bonds are at the 9th and 12th carbons from the acid (right) end of the carbon chain.

The most active CLA isomer is cis 9-, trans-11 CLA. But here is what has me puzzled: why is linoleic acid called cis 9-, cis 12-octadecadienoic acid—where the two double bonds are at the 9th and 12th carbons—when in omega-6, which is linoleic acid, the first double bond occurs at the #6 carbon atom from the left end? It seems like there is an inconsistency here—omega-6 being named by the #6 carbon from the left end, yet the cis 9-, cis 12-octadecadienoic acid name seems to pertain to the naming of carbon positions from the acid (right) end of the molecule. Could you please clarify?:

A: To answer this question about fatty acid nomenclature, you have to know that there are two systems for naming fatty acids. The first is the Delta system, which counts from the Delta (acid) end of the fatty acid and is used by Chemical Abstracts and the Merck Index. This system starts counting carbon atoms at the acid end, puts the carbon number where the double bond first begins and identifies whether it is a “cis” or “trans” bond before that. The word before “acid” just counts the carbon atoms (in this case 18 carbon atoms) and shows that there are double bonds in the structure (di). Linoleic Acid is (cis, cis) 9-, 12-octadecadienoic acid.

The second system counts from the Omega (methyl) end of the fatty acid. Omega (w) is the last letter of the Greek alphabet. Linoleic acid is (cis, cis) w 6-, 9-octadecadienoic acid. If you count these systems out, you will see that the cis 12 of the Delta system is bonded to the cis 6 of the Omega system (18 carbons total). The Omega system is sometimes used to show families of fatty acids that all have the same Omega value, as that end is not affected by the enzymes that change fatty acids inside our cells.