If you're eating 6,500 calories per day in lean meats, fish, nuts, vegetables and fruit, I absolutely guarantee you will become fat without rigorous physical activity.
Calories in/calories out is what matters when it comes to weight. If your concern is cholesterol or blood sugar, on the other hand, your diet and genetics play a huge role in that.
Let's not forget about the teacher who ate nothing but Twinkies and cupcakes for several weeks and lost a tremendous amount of weight and lowered his cholesterol.
http://www.cnn.com/2010/HEALTH/11/08/twinkie.diet.professor/...
Now, I'm not suggesting that anyone go on a Twinkie diet, but the biggest takeaway from what that professor did is that the amount of calories you consume is important when it comes to weight loss, and subsequently lowering cholesterol.