You can do GH without slin, however, you will have to keep an eye on your blood sugar. In some, GH will make them type 2 diabetic and insulin will help gaurd against this side effect if you have trouble. The slin won't make you fat while on elevated GH levels so that shouldn't be much of a concern. You're not looking to take loads of slin- just a small amount to help out your own body's insulin production and to get the synergistic effects of slin and GH together.