Is Visalus a scam?

While the product they market seems to have some legitimate use, even though not FDA approved, I am rather bothered by the fact that it's a MLM enterprise.
What do you think?

PDF Attachement Spam

During the last few days I have received a couple of the online-pharmacy spam e-mailsinto my g-mail account. Thesee-mails were not filtered out by GMail's spam detecting bots. Essentially, these e-mails were without any inline text, but with a PDF file attached.
My conclusion: Gmail anti spam algorithms aren't aware of PDF files content.

Edit: Adobe has commented on the possibility of PDF spam filter implementation. Read about it on CNET.