How many times have we heard various rules for losing weight? You know the ones... dietary supplements work magic, carbs make you fat, gaining muscle makes you gain weight and late-night snacking packs on the pounds. We're fed all these diet myths everyday, so it can be difficult to sort out what's true and what's not. NBC News Chief Medical Editor Dr. Nancy Snyderman busts all those diet myths and more in her new book Diet Myths That Keep Us Fat: And the 101 Truths That Will Save Your Waistline--And Maybe even Your Life. Plus, she confirms a few truths that we've heard tossed around, too.

Diet Myths can be your healthy eating encyclopedia when one of your girlfriends tries to tell you another one of those crazy diet stories. For example, cutting out as many calories as possible in your diet DOES NOT help you lose weight. I've had a friend tell me that once and, honestly, I believed her. The doc would say that consistency is what helps you lose weight, not simply dropping calories quickly. Yes, you need to eat less, but also do it consistently (yes, for more than one week) while burning more calories. Dr. Snyderman gives you an effective breakdown of what's true and what will harm your health. Some of it is simple stuff, but not everyone knows it--it's easy to be sucked into believing the latest diet dish. We found some diet truths that we never thought were true to help you get on your way to losing the weight... for good!

• Belly fat is linked to dementia. Those who are overweight and have a large belly are 2.3 times more likely to develop dementia than those with a normal weight and belly size.
• Monosaturated fats may help flatten your tummy. Avocados, olive oil, canola oil and peanut oils contain these fats.
• Dark Chocolate is a dieter's friend. It helps blood flow, promotes normal clotting and improves circulation. The darker the chocolate the better.
• Calorie-free soft drinks may make you fat. Artificially-sweetened drinks, despite its low calorie content, make you crave more sweets. Thus, you end up eating your sweet calories later.
• You need carbs to burn fat. Before you're quick to pass on the bread, you may need to think twice, as you need fuel for your weight loss.

For more surprising diet facts, check out It's True... Dessert Can Be Dinner. Or, you can find more information on the book at RandomHouse.com.