Is it unhealthy to lose 7 pounds in 2 weeks?

Answer 1

Yes and no. Crash diets are a bad idea, and you shouldn't try loosing more than about a pound a week. This is risking that you're actually loosing muscle mass instead of fat, which is the opposite of what you want if you're trying to loose weight. Muscles are what improve your metabolism! so, if you're trying a diet that has you loosing that amount of weight, and you're managing it well and are still feeling energized then yes, although if you're trying to loose weight from fat, it's a better bet to go at about a pound a week. One pound of fat is 3500 calories - so if you cut 500 calories a day, you should be dropping the pounds in fat, instead of muscle!