There's a big difference in ketosis and ketoacidosis, not just in the quantity of ketone bodies, but the context. For diabetics, the presence of large amount of ketones (ketoacidosis) indicates that the body cannot use glucose as a fuel source, even if its present in large quantities. This indicates that insulin isn't working and the body has to break down protien instead, which are your muscles. This is very bad. You have large amounts of blood glucose, which damages kidneys and eyes etc, and you're breaking down your muscles, which is never good long term. Let me repeat: This is bad.

Ketosis, on the other hand, is actually a normal phenomenom. Your body is designed to switch fuel sources fairly easily, although this ability has been diminished with our non-stop carb intake. Ketones are produced when your body breaks down protein, whether its from diet or your own body.

The misconception that paleo is a more natural sourced Atkins diet raises a lot of (unfounded) fears of ketoacidosis. First off, the emphasis on fats and veggies instead of unlimited proteins usually doesn't kick off ketosis on a regular basis. Periodically, I'll get some ketone strips for analytical purposes to see what my body is doing, but not to try to get into ketosis. What I have observed is that I almost never get into ketosis, and if I do, its slight.

Another ketosis factor is exercise, which is part of the paleo lifestlye (NOT A DIET!!). I am never in ketosis immediately after exercise. Why? I've just used all the fuel! If I don't eat anything for a few hours, it'll kick in big time, but I almost never do that.

Now, as far as the brain using glucose... Your brain can use both glucose and ketones for fuel, EXCEPT for some small parts of the brain which needs to use glucose. The amount of glucose needed to fuel this is about the same that your liver can produce from protein. Pretty convenient. You're in school, look up the amounts.

To answer your question, No. The chances are minimal, if non-existant, that you'll get into ketoacidosis on a paleo diet/lifestyle.

1. Paleo is not a low-carb diet. Thus the amount of ketones in your blood is not particularly high. It might be raised slightly, but the amount is negligible. You CAN be low-carb Paleo, if you want and that WILL raise your ketones by a significant amount.

2. Ketosis and Ketoacidosis are not the same thing and is one of the oldest and stupidest health myths out there. If you're not diabetic, you won't get ketoacidosis. And even then.

3. The brain utilizes ketones and glucose. Tell your teacher to do a bit more research on how John Hopkins hospital treats epileptic patients - with a ketogenic diet.

There's no carbohydrate in meat. There might be small amounts of glycogen if you were to kill the animal and consume the meat FRESH. But by time it gets to your plate, it has no glycogen and thus it's 100% useless as a source of carbs.

http://josepharcita.blogspot.com/2011/03/guide-to-ketosis.html

All of this research is out there if you and your teacher are willing to look.

Here is a blog of a formal Paleo-eater. He has been Paleo for 14 years and developed different disorders. So now he is more like Weston Price or gluten-free whole foods - not sure how to describe it. He is eating more grains and tubers.

Here is his blog: http://donmatesz.blogspot.com/2011/06/farewell-to-paleo.html

Dear Paleohackers, please do not consider this link or my answer an attack on Paleo. I think each case should be viewed on an individual basis, and it will help the person who asked the question in his search. I personally would not follow this guy's diet, but hey, what works for one not necessarily works for another. Plus his wife is a vegetarian now (being a formal Paleo).

A good resource for you are the works of Volek and Phinney. They explain very well what happens to the body with a low carbohydrate diet. This is not necessarily the same thing as what happens to someone on a paleolithic diet because the paleo diet can include lots of starchy vegetables and sugary fruit if someone wants it.