If it unhealthy to lose too much fat, build too much muscle too fast?
What would be a health and realistic pounds of fat reduction or pounds of muscle gain in a week?
a realistic weight loss is around 1 pound a week. If considered obese then 2 pounds a week is fine. If the bodyfat level is below 10 percent then half a pound a week is probably best.
Muscle gain for a beginner who eats the right amount of protein, enough food and follows a good mass building routine consistently I would say slightly under half a pound of muscle gain a week is realistic. Some with better genetics may build more, some less. Of course the more muscle already on your body, the slower you will gain it.
Here's the secret to many of these makeovers or rapid weight loss success stories: Start with somebody who is already active and fit, but has to take some time off due to injury. Have them gain a lot of weight while recovering from the injury. After they've recovered, have them go back to their old active and fit lifestyle and add in whatever miracle makeover plan you're trying to sell. Voila, impressive weight loss and fitness improvements.