In the nineteen nineties, the drug company Parke Davis paid another company, Medical Education Systems, to produce journal articles in support of one of its drugs.

VOA: special.2009.10.08

Studies in the Journal of the Academy of Nutrition and Dietetics and the American Journal of Preventive Medicine also support the benefits of journaling, although weight loss in both studies was modest.

CNN: Journaling helps woman lose half her body weight

Smith points to a study that appeared in the New England Journal of Medicine in February 2002 to support his point.

FORBES: Running Vs. Medicine

The letter is part of a growing campaign to force the industry to be more open and has support from the British Medical Journal and Sense About Science.

BBC: Trust of medical volunteers 'betrayed'