Excerpt: How to Combat 'Your Big Fat Boyfriend'

Feb. 24, 2009— -- Do you find yourself gaining weight the second you're in a relationship? According to author Jenna Bergen, many women often pack on the pounds as a result of their partners' bad eating habits. She takes a look at "loveinduced pounds" and offers advice on how to combat them in her book, "Your Big Fat Boyfriend."

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One of the first steps in staying thin when you're in love, Bergen says, is to get your significant other healthy. To do this, she recommends determining what kind of guy he is. Here is a look at Bergen's "Know Your Guy" chart:

When it comes to getting your Big Fat Boyfriend healthy, the first thing you've got to know is why he's currently behaving the way he is. There are a few types of guys -- some have multiple issues, though we love them anyway, oddly enough. Here's how to deal with each.

The Used-to-be-Thin Guy:

For most of his life, he's been able to eat whatever he wants and still stay thinner than a flagpole. Without an ounce of fat sticking to his ribs, he's never felt the need to pay attention to how the junk he shovels down might be affecting his insides, like his heart. Then, his 20s hit, he got stuck behind a desk, and his roaring metabolism started to slow. Result: a few too many pounds around his middle.

What he's feeling: Lost and confused. The same burgers and fries he used to devour have turned against him. He's never even thought about ordering a salad or stir-fry when eating out.

What he needs: Nutrition 101. Start explaining -- slowly, you don't want to scare him -- the basics. Explain why he should increase his daily intake of fruits and veggies (if you start out telling him to cut out his favorite foods, you will most likely be met with resistance). Little by little, introduce him to other aspects. ("Honey, here's the nutritional info, right here on the back of the box. This is how many calories are in a serving. This is how many Cheetos are actually a serving.") Little changes can make a huge difference in his health and his belly.