I'm 18 and have been overweight for a while. I am about 220 pounds and want to lose atleast 90 pounds. I've been exercising, cardio biking, and im starting a healthy eating plan (im on the south beach diet), I want to know if theres a good chance my tummy will go down and the skin not be so stretched out? I dont have bad stretch marks or anything.

Homeopathic treatment to loose excessive fat and weight :-
The safest and sure fire way to loose weight and excessive fat is PHYTOLACCA BERRY Q(Mother Tincture) 20 drops thrice a day in a sip of water half hour before or after meals will start showing results in 30 to 45 days of regular use and will cure flabby or sagging tummy and will make your skin look fresher and tighter and has no side effects and has no complications whatsoever ! Avoid taking Chocolates Coffee Mints and Red Meat while taking homeopathic medicine.
You can get homeopathic medicines from Major Herbal Shops and Homeopathic Stores and they are quite inexpensive.
Take Care and God Bless !
P.S
Its good to exercise along, all you can, Walking, Swimming, Cycling etc whichever you prefer !

Take fish oil capsules three times a day they help a lot with sagging skin.
Fish oil is rich in omega 3 fatty acids and many other minerals that will help nourish the skin and help support elastin. This is what causes the skin to snap back into place when you pull on it.
Also drink lots of filtered water. Make sure you don't drink tap water unless you have well water. Tap water has fluoride in it which causes wrinkles and also causes the body to not be able to absorb nutrients as well. Chlorine does a similar thing to the cell walls.
Do not drink sodas because even diet sodas will cause skin to loose its supple texture.
Drink green tea as it is a natural appetite suppressant.

hmm weight loss