A study just published in an American Heart Association journal links atherosclerosis -- hardening of the arteries -- to car exhaust. The diesel exhaust fumes robbed what is generally known as good cholesterol, HDL, of its protective powers, and showed non-reversed blood and liver damage.

In this video, health-care analyst David Williamson discusses the implications of this study and what impact it could have for investors in a variety of industries, including transportation, energy, and health care.

Follow David on Twitter: @MotleyDavid.

David Williamson has no position in any stocks mentioned. Follow David on Twitter: @MotleyDavid.

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