Everyone has different levels of glucose tolerance. But I think it is generally agreed that refined carbs aren't good for you whereas carbs from things such as above ground non-starchy veggies, nuts, legumes, quinoa, berries, etc.. are. And again in the amounts suitable for your particular metabolic fingerprint and weight loss goals.
George Cahill, former professor at Harvard Medical School: "Carbohydrate drives insulin drives fat". I personally believe all the cheap refined carbs including sugar and finely ground white flour are the main culprits of obesity, cardiovascular disease and type 2 diabetes.
Recommended Book: Why We Get Fat by Gary Taubes