yeah, generally risperdal negatively affects the blood lipids, resulting in weight gain, potentially higher cholesterol and risk of diabetes. All the atypical antipsychotics do this. The degree to which someone is affected will depend on metabolism and environmental factors like exercise etc.

one of the reasons is that these meds make it harder for you to feel full.. they affect the vagus nerve. In our modern world we don't eat to satisfy hunger, we eat until we feel full. With that ability compromised, many people continue to eat increasing amounts of food. This is obviously controllable through control of portions and quantity but would take a serious conscious effort.

another reason is that many psychiatric drugs seem to increase carbohydrate cravings. We eat more starchy sugary foods. This is an apparent side effect in it's own right, but often couple with the fact that carby foods are cheaper.. and many of us live on very tight budgets, esp those on disability, etc.

having said that... two things: one is that risperdal is like a little wonder drug for me, it works really well.. and the other is that i won't take it due to the weight and cholesterol issues.