Thats a tough question to answer but I will give it my best shot. If you are a healthy individual you would normally not have ketones. Ketones are the result of the body burning fats for fuel. People who go on starvation diets and loose large amounts weight at once will often times have elevated ketones. So to answer your question I would say yes they are normal except at elevated levels. There a number of things that can effect that level. Diet is one, being dehydrated is another one, and of course having elevated blood glucoes levels for extended periods of time. Try this sight and see if it helps clear things up. IOH - urine test for ketones
yeah we have to watch that we don't get 'diabetic ketoacidosis' which is high level of ketones in the blood stream combined with severe lack of insulin, and too much sugar in the blood which becomes 'toxic'. You have to get yourself to a hospital emergency dept quick as this is life threatening. Also they don't like diabetics to have 'ketosis' which is a high level of ketones in the blood... you have to get to hospital with that too to get checked out. You can buy ketone test strips (which tests your ketone levels in your urine) if you're concerned to check what your ketones are. This is a good idea if you're sick as this is when we're more likely to get this problem with diabetes. I only had one experience of being told my ketones were too high and that was when I was in hospital and didn't eat all day. I was then forced to eat to get ketone levels down. I hope this helps.