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Ask the Experts


All of the articles I have read about the supplement SAM-e recommend the butanedisulfonate form.

However, all of the SAM-e supplements I have seen sold at retail do not use that form of SAM-e, but rather the 'tosylate form.'

Is the 'tosylate form' really better? Why?

Also, where can 'butanedisulfonate' SAM-e products be found?

Answered by: Philip Muskin

This is a good question. Unfortunately, the plant that used to manufacture the butanedisulfate form in Italy has been closed. However, the tosylate form is effective. More important are the following factors:

1. The correct isomer. Many bargain brands from Asia contain inactive isomers.

2. The quality of the manufacturing of the tablet to reduce degradation from oxidation on the shelf.

3. Whether the company tests its product for shelf life. Many brands lose potency after 3 months on the shelf.

4. The packaging. The tablets should be individually sealed in blister packs.

Two companies that meet these standards are NatureMade and the pharmaceutical grade SAMe products, SAMYR and Donamet, sold by IAS (