Ketone Question: Dietary Fat vs. Body Fat

[kmuldrow]

This is not really another thread about ketosis and ketostix but a question about what they measure.

I was going through the archives and reading about Ketostix.

I gathered that what's on the stick shows the ketones being produced from both the dietary and body fat that isn't being used and therefore is expelled through urine.

My question is how do you know which fat is being burned and which is being expelled? For example, if a person is showing a moderate reading, how are they to know how much of it is from the amount of dietary fat needed to successfully take this journey and their own body fat?

[msanjelpie]

Eating fat and expelling it from your system does not cause ketones. Otherwise we would be in ketosis even when we're not on a low carb diet...

So you can be assured that when your body is producing ketones that it is from fat being burned off of your body. Lipolysis.

[Georgiana]

Originally Posted by msanjelpie

Eating fat and expelling it from your system does not cause ketones. Otherwise we would be in ketosis even when we're not on a low carb diet...

So you can be assured that when your body is producing ketones that it is from fat being burned off of your body. Lipolysis.

That's not correct. Our bodies can (and are!) very well producing ketones from the fats we are eating. Lipolysis is simply defined as the process of breaking down lipids to produce fatty acids, and the source of these lipids is not exclusively body stored fat --- it is dietary fat too, among other sources.

Of course, eating a big plate of fries won't put anyone into ketosis, but that is simply because the body is getting its energy from carbohydrates and, while glucose is present and sufficient, the insulin that is released will tell the body to produce glycerol from glucose. Fatty acids are absorbed from the blood and, if insulin is present, stored as fat into fat cells. So, as long as enough energy is provided from carbohydrates consumed (as it's the case with this big plate of fries), the body will store fat, not "expell it from your system". If not enough fuel comes from glucose, the body can use its fat stores (that's why people also lose weight on low fat diets), but ketones, if produced, will likely not be seen on ketostix because they are used for energy.

To answer the OP's question. Ketostix can't tell the source of acetoacetone (this is the ketone you are peeing). Moreover, their color is affected by the source of fats in your diet. For example, eating a lot of coconut oil might make ketostix darker, because coconut oil is rich in medium-chain fatty acids, which can be easily absorbed and used to produce ketones. Also, the color on the ketostix won't tell you whether you are losing or gaining weight. As long as we are following Atkins correctly and eating only enough to satisfy our hunger, the ketones will come primarily from stored body fat and we will be losing fat. But the best way to test for fat loss is not with ketostix, but with a measuring tape.

[kmuldrow]

Okay. I was just asking because I have about 2TBSP per day (as measured by the lines on the package) of pure butter and I wanted to make sure that the butter is not what's making me be "moderate". I've never had a dark purple strip but that's probably because of my water and exercise.

Thanks.

[msanjelpie]

Thanks Georgiana... I can always rely on you to set me straight

[Aways2Go]

Is there a preference in the body as to which to burn first, body fat or recently consumed fats? Does it depend on the type of fats eaten? Is it a quantity issue (eg, is there a formula of fat grams needed for fuel per pound of body weight at a given level of exercise/activity daily in the absence of carbohydrate intake, etc)?

I find this topic very interesting. I don't want to obsess over it, but would be curious to learn more.

[kmuldrow]

Originally Posted by msanjelpie

Thanks Georgiana... I can always rely on you to set me straight

I was just re-reading DANDR and it says "They [ketones] are derived from fat when lipolysis is occuring, and are the other source of fuel that energizes our cells and powers our brain and other vital organs."

So perhaps you both are right in a way?

By that I mean that the dietary fat could be what's represented on the ketone stick and it's a sign that lipolysis is happening on the inside?

[Georgiana]

Originally Posted by kmuldrow

By that I mean that the dietary fat could be what's represented on the ketone stick and it's a sign that lipolysis is happening on the inside?

The ketones showing on the stix (acetoacetate) come both from dietary and body fat, not only from one of these two possible sources. But you're correct saying that they are an indicator that "lipolysis is happening on the inside".

[FwL]

Research is showing that fat isn't just some innert storage area where excess calories end up. Fat is active tissue that is regularly taking on and releasing nutrients. It's when this process gets stuck (too much insuline in the system, perhaps) that we start adding on the pounds.