Do not smoke or chew tobacco.
Explanation: Tobacco exposure, including secondhand smoke, reduces coronary blood flow; causes vasoconstriction, endothelial dysfunction, and thickening of the vessel walls; increases carbon monoxide; and decreases oxygen. Because it is highly addicting, beginning smoking in the teen years may lead to decades of exposure. Teens are not likely to experience metabolic syndrome from obesity but are very likely to use tobacco. Avoiding stress is a less modifiable risk factor, which is less likely to cause heart disease in teens. The risk of smoking outweighs the risk of alcohol use.
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