Too much sugar is never good for anyone. Just try to stay away from too many sweets and chocolate, ice creams and processed foods. Try to eat a lot of veggies and fruits
Do you mean like with gd? I think its refined sugars and complex carbs.
Limit Caffeine obviously.. I heard artificial sweeteners because they haven't been tested in pregnancy. Other than that nothing i know of. Was there something particular you were referring to?