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9 of 12
Drinking Diet Soda Every Day
Vice-O-Meter: 8

The Harm:
The good news is that artificial sweeteners (like aspartame and sucralose) found in "diet" or "light" soft drinks won't give you cancer. But large-scale studies indicate that they can lead to weight gain. Increasing evidence suggests that fake sugars activate the brain's reward pathways differently than natural sugars do. As a result, you don't feel as satisfied—and your appetite actually increases.

The Cure:
Switch to juice—or better yet, develop a water habit. If you must drink soda, have a regular and dilute it with seltzer.
As a reminder, always consult your doctor for medical advice and treatment before starting any program.