A cardiologist at the University of Maryland reports that watching Something about Mary — a comedy starring the glamorous Cameron Diaz — is better for the blood flow than taking in Private Ryan — a harrowing war movie with a famously gory opening. A fascinating conclusion, brought to an eager public by a sample of — 20.

How conclusive is an experiment involving fewer people than most office workers can see from their desk? Was it Diaz’s cheeky humour or the study’s requirement that participants go teetotal for 24 hours before participating? Is this a scientific breakthrough, a clever promo from Diaz’s agent, or just another research grant being used to state the obvious: it’s good to laugh? More research, and several professorial salaries, will surely be needed to test such bold conclusions.

Two other health reports today also support old adages. A survey at Alabama University suggests that Viagra could cause vision problems — a message not far from the warnings that headmasters used to give over-eager boys. The worrying-sounding findings are backed by a survey of only 76 patients, so new studies will no doubt be required for the lawsuit.

Lastly, a Seattle group finds that exercise is good for you, and may even diminish Alzheimer’s. The jogging lobby will be delighted, as will makers of sports shoes and deodorant. There is a decent sample, and exciting implications. But experts call for further research. Is bowls better than table tennis? What about mowing the lawn? Researchers are no doubt considering a proposal to research the effects of research on researchers. More research grants, please.

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