That really depends on the kind of weight loss diet that you're looking to take up. One thing that you should remember is that weight loss is a gradual process. You shouldn't try and speed up the process in anyway. I know that diet pills and their claims can be quite tempting, but at the end of the day - they're drugs. You can follow a GI diet, or you can even follow a standard diet with a lot of fruits, cereals, nuts and legumes that can keep you healthy. Avoid junk food in all their forms. Exercise also plays a key role. These will help you lose weight in a healthy manner. Losing weight within a month or two through crash diets is sure to affect your body.