Here is a recap of the stories that appeared last week at Science-Based Medicine, a multi-author skeptical blog that separates the science from the woo in medicine.

Radiation from medical imaging and cancer risk (David Gorski) CT scans and other imaging procedures have revolutionized modern medical practice, but the associated radiation can cause cancer. We should keep the risk/benefit ratio in mind and use these studies only for valid science-based indications.

Multiple Sclerosis and Irrational Exuberance (Peter Lipson) The media have hyped a new treatment for MS by one doctor who claims that MS is caused by impaired venous blood flow in the brain and who does a surgical procedure to correct it. Pending further research, his claims should be approached with caution.

Medical Fun with Christmas Carols (Harriet Hall) A bit of lighthearted holiday humor, adapting Christmas carol titles to medical diagnoses.

Lithium for ALS – Angioplasty for MS (Steven Novella) Pilot studies are unreliable: most new ideas do not pan out. As a cautionary example, lithium was touted as a breakthrough for treating ALS, but further research showed it didn’t work. Scientists withhold enthusiasm pending further research -- not out of negativity but because of hard-earned experience.

“Toxins”: the new evil humours (Amy Tuteur) The belief that we are swimming in a world of “toxins” that cause disease and that require “detoxification” treatments is not based on science, but on a reinvention of old myths like miasmas and evil humours.

2009’s Top 5 Threats To Science In Medicine (Val Jones) The worst culprits are congress, mainstream media, “quackademic” academic medical centers, NCCAM, and new media. Dr. Jones explains why.

Buteyko Breathing Technique – Nothing to Hyperventilate About (Joseph Albietz) A Russian doctor named Buteyko claims that his breathing techniques can cure asthma and 150 other diseases. Consciously slowing breathing may have a calming effect, but Buteyko’s physiologic explanations are demonstrably wrong and his method is not supported by any credible scientific evidence of objective benefits.