What chima said is accurate. In addition, the statement that insulin stores carbs as fat isn't correct, either. What actually is happening is that when you ingest foods rich in glucose, it inhibits fatty acid burn. As a consequence, the dietary fat you consume along with the glucose is stored. Example: you eat a baked potato with butter. The starch elevates your blood glucose and there is an ensuing insulin rise. Glucose is burnt preferentially and the dietary fat from the butter is stored. Of course, nothing is 100%. You aren't burning 100% glucose and 0% fat, but the ratio is skewed heavily in glucose's favor to the point where FFA oxidation is relatively negligible versus a fasted state.
Originally Posted by Alfi56
Of course, none of this matters if you aren't consuming a caloric surplus. If you ARE consuming a caloric surplus, though, it's the dietary fat being stored. Unless you're eating a nearly zero fat diet (>10% total daily calories), it's pretty much always the fat being stored.
Don't put your trust in anyone on this forum, including me. You are the key to your own success.