Ketones in blood vs consumed fat

(Tim) #1

Does the presence of ketones in the blood necessarily indicate that body fat is being burned? I’ve read many articles that say or imply “yes”. You’re in optimal ketosis if your reading is x to y.

However, my understanding is that ketones in the blood come from breaking down (“burning”) fat. On a ketogenic diet, I’m also consuming fat. Is the consumed fat also broken down in the same way? If so, then is it possible to have ketones in the blood, but NOT be burning body fat, but simply burning the consumed fat? In other words, if I ate enough fat (let’s say for simplicity that I’m not eating anything but fat; not the case, but for clarity of the question) to supply my energy needs for the day, then presumably I would have low glucose and insulin levels, and I’d have ketones present in my blood, but I would burn no body fat,

(Ethan) #2

I would say that ketones result from three sources:

(1) Body fat being broken down
(2) Consumed fat (triglycerides) being broken down
(3) Consumed exogenous ketones

(VLC.MD) #3

You have the ideas right.
But I’ll say if the insulin levels are low enough long enough, you’ll likely start burning stored fat into ketones even though you technically have enough fat in the blood to cover the body’s needs.

(Tim) #4

I found some information related to my question in this very interesting article:

It also references another article that I had reviewed, a medical article on the correlation between acetone in the breath and fat loss:

It happens that I am using a breath-based meter, so I am in fact measuring acetone.

(Ken) #5

Ketones are produced when glycerol from fat molecule breakdown goes back to the liver and is converted to ketones.

#6

Great article on the breath analysis… long but very informative and and not too excessively complicated or scientific.

The good news I gathered from it is that if I’m seeing a .2 on my cheapo meter I should be losing .5 pound of fat a week… did I read that right?
Sue

(You've tried everything else; why not try bacon?) #7

Yes, ketones are an intermediate product of the metabolism of fat, whether from your body’s fat stores or from your diet. If you are eating fat to satiety, your body will tell you when to stop, and that is generally at a level at which there is plenty of room to be metabolizing stored fat along with dietary fat. (Assuming, of course, that you still have stored fat available. Once you are in the maintenance phase, you will need to be getting all your calories from your food.)

(Tim) #8

That was actually the genesis of my question. I was wondering, if my meter says X, what does that mean in terms of fat burned, and that turned into “does it prove I’m actually burning body fat at all?”

Here’s another interesting article that I just read that’s somewhat related:

(Ethan) #9

This is why I don’t ever measure ketones alone. I always measure them at the same time as I measure glucose. If my ketones are 0.4, but my glucose is 90, I am doing great. However, if my glucose is 130 or higher with that same 0.4 ketones, I’ll think about what I just recently ate. It’s likely then that I had some accidental carbs.