Rat Study: Is Weed Slowing Blood Vessels and Clogging Arteries?

Or is prematurely climaxing science the father of all fear-mongering?

A study conducted by the American Heart Association recently found that rat blood vessels took three times as long to recover functioning speed after exposing the rodent to marijuana smoke, in comparison with second-hand tobacco exposure. While the study's researchers acknowledge that the slowed processing of blood flow is indeed only a temporary effect, they go on to project that these results could indicate development of long term effects that increase incidence of hardened and clogged arteries, often linked to stroke and coronary disease. All of this is based on researchers stating it is “likely” rat arteries reflect the response of human arteries.

Sounds scary right?

Well, I call bullshit. And so does the National Center for Biotechnology Information:

Howard Jacob, PhD at HudsonAlpha institute for biotechnology informs us that "There is only 10% predictive power, since 90% of drugs fail in the human trials" in the traditional toxicology tests involving rats. With a 90% failure statistic, I wouldn’t quite go as far as the American Heart Association is saying it is “likely” that rat arteries reflect human anatomy at all, quite the opposite in fact.

Further research conducted by the University of Iowa and Mayo Clinic in Rochester, Minnesota on the success of rat-human research, and animal-human tests in general, found that the studies it conducted on rats in relation to arteries and stroke proved consistently “disappointing.” The clinic identified 25 different compounds that proved to be successful in treating stroke and other such afflictions in rats, zero of which compounds had any success in human trials. 

The Mayo Clinic researchers went on to conclude that: “An over-reliance upon such models may impede rather than advance scientific progress in the treatment of this disease.”

So, to paraphrase, not only are these rat studies ineffective in translating to human-based results, the scientists encouraging them are actually getting in the way of studies that might find truly applicable results.

Should you be worried about developing stroke and heart disease if you go a little heavy on the greens? Well, yeah, of course. If you’re a rat that is. If you’re a human, who the hell knows? Not science.