Diet Friend or Foe

• She knows precisely how many calories are in 20 peanuts and exactly how many minutes she'll have to spend on the treadmill to work off those calories. She does all the things Tiffany talks about doing, and then some.
  

What to do: Obsessing about your diet and weight can be just as dangerous as doing nothing at all. In fact, it can lead to life-threatening eating disorders such as anorexia nervosa (starving to be thin) and bulimia nervosa (habitual binge eating and purging). If you think your friend is in danger, encourage her to seek help immediately and do not participate in your friend's dangerous behaviors in any way

• Cheeseburgers, french fries and cheesecake. Nothing is off limits to Carol the Clueless. She has never seen the inside of a gym, and she doesn't think twice about smoking a cigarette.
  

What to do: If you don't see this friend very often, use this time with her as an opportunity for an occasional indulgence (sharing a sundae or splitting an order of fries, for example). Just be sure to plan the rest of your day accordingly. However, if you see this friend on a regular basis, you need to mentally prepare yourself to make thoughtful decisions for your health instead of impulsively following her unhealthy lead.

• From Atkins to the Zone to the Grapefruit Diet. If there's a fad diet being talked about, Fanny is following it.
  

What to do: Fad diets are only temporary solutions for lifelong problems. A carefully planned weight loss program requires consistently tackling both sides of the energy balance equation: calories in and calories out. Instead of jumping on the latest and greatest fad diet with your friend, seek the advice of a trained dietitian who can help you develop an eating plan you can follow for life.