The best way to avoid the loose, saggy skin that often is an effect of losing a lot of weight is to have a plan before you begin your weight-loss journey. If you lose weight gradually -- no more than 1 to 2 pounds a week -- you have a better chance of avoiding loose skin. But even if you have already lost the weight, there are some methods that might help to somewhat decrease the loose skin.
Drink plenty of water. Water hydrates your skin, which helps make it more elastic so that it can better fit your new body. Women should drink about 91 ounces of water a day, and men should drink about 125 ounces, according to the Institute of Medicine.
Eat the right foods to maintain elastic skin. Foods that contain protein to help form collagen, which plumps thin skin, are cottage cheese, milk, nuts, seeds, tofu, legumes and fish.
Stay out of the sun, and avoid tanning beds. Both decrease the skin's elasticity. Also avoid chlorinated water and water that is too hot for the same reason.
Undergo surgery, if necessary. Sometimes the only way to get rid of excess skin after losing an excessive amount of weight is through body-contouring surgery. The surgery involves cutting an area where the excess skin will be removed. The area will then be stitched up, and some scarring will occur.