I am in the middle of some study in nutrition and while I have no qualification I would look at your carbohydrate intake. Perhaps you arent eating many? When you are pregnant you definately need more carbs but you want to make sure they are good ones like whole grain breads etc. Look for things that have a low GI as they tend to have the complex carbs in them. You definately dont need fat increased in your diet though. Smoothies are great for getting something in when you arent feeling great but I would only have one a day and that isnt going to fix your ketone levels.

When you are trying to lose weight one of the main ways of doing so is generally but cutting most carbs out of your diet. What that does though is makes you body eat itself away and ketones are the byproduct of this whole process. I have even seen naturopaths get their clients to pee on what is called ketone sticks to measur the ketone levels in the urine. Ketone levels that are really high can be pretty dangerous for your liver though and play havock with your sugar levels.

I hope some of this has been helpful, it is all just coming out with no thought.