Q: I use diet soda to cut down on daily calorie intake. Good or bad idea?
By Heather Bauer, RD, CDN | May 2008 | SUBSCRIBE | VIEW ARCHIVE

A: Bad idea. Most people who drink diet soda are drinking it as a replacement for water and water is always the best hydrator. Water can actually help boost metabolism. There’s some evidence that suggests that diet drinks can even have a negative effect on weight loss. A recent study found that study animals who ate yogurt sweetened with saccharine versus those who ate it sweetened with sugar experienced weight gain. How’s that for depressing? They’re not certain why this would happen. It could be some metabolic change stimulated by the artificial sweetener or it could be a behavioral change (I’m eating low-cal yogurt so I can have the cupcake.) Some researchers speculate that the artificial sweetener actually triggers your insulin levels and if your insulin levels are triggered you will crave and therefore eat more carbohydrates and more calories overall. In my experience, clients who drink diet soda aren’t drinking water. Despite the fact that some research indicates that water is not important for weight loss, I have seen over and over again clients who are perfect eaters/exercisers but drink no water and can’t seem to lose an ounce. When I insist they up their water intake they lose weight. There is no better research then 10 years of experience! If you are a diet soda addict, try to reduce your intake if you can’t cut it out entirely and make it your goal to get in 6-8 cups of water before drinking your diet soda (this trick always works because there is only so much fluid you can fit into your body : ) . Also try to get in 1 liter by lunch…busy people always wait until the end of the day and there is no way to cram it all in after 6 without having your sleep suffer from the constant bathroom trips. I give a host of tips on water in The Wall Street Diet including recommended daily amounts and how water intake affects weight loss. (You can find a hot tip on the dangers of “diet” mixers on page 134.) Bottom line…less diet soda and more water is the way to go to reach your goal.