Basic ketone question - which comes first?


I’m not new to keto (even though I’m newly back, again). And I assume that since I’ve been reading, on and off, everything I can get my hands on over the years, that I know the science behind it. WRONG. I was trying to explain to a curious friend the other day the basics of eating a keto way of life, and why I was testing my blood, and I realized I didn’t know what I was talking about. Yes, I know we try to stay within our individual macros. I know about switching from carb burning to fat burning, I KNOW about keto flu and why, and I know ketone levels fluctuate.

What I don’t remember (or never knew?) is: isn’t a ketone a byproduct of our bodies burning fat? I thought it was produced once we were in ketosis, and the number on the meter showed us how MUCH fat we’ve burned recently. But then I have to ask, why does anyone try to artificially increase their ketone levels by adding them with a supplement? (Yes, I have MCT in my cupboard but never did use it). What is the point of adding ketones to our system when our systems can and should make their own?

I’ve been searching for the answer but not finding it… yet. Can anyone help in layman’s terms?

(Full Metal KETO AF) #2

MCT and ketones aren’t the same thing. It’s medium chain triglycerides. An easily used fatty acid source. And you are correct about exogenous ketones, not necessary because taking them “fakes” higher ketone levels. Unless you have a specific need for high ketones, cancer, epilepsy or maybe the autism spectrum I don’t believe they are helpful. People seem to think if they’ve been cheating on carb intake that they put you back in ketosis faster because you can measure ketones again in your blood but it doesn’t mean you’re in ketosis. :cowboy_hat_face:

(Michael - When reality fails to meet expectations, the problem is not reality.) #3


Cranking up energy and alertness mainly, re-living that “clarity” that most of us only get for a short while when we first start and sometimes when we fast. Many people doing keto for medical reasons also benefit from high ketone levels. If I could afford to use exogenous ketones as a pre-workout I’d do it daily. Most of us have forget what it feel like to have the flood of ketones flowing… it feels AWESOME!

(Jenna Ericson) #5

When you are on a ketogenic diet you are not necessarily using ketones for the majority of your energy. You are using fatty acids for the majority of your energy. When you go on a low carb diet the main reason why you would be producing ketones is to feed your brain once your glycogen stores have been depleted. Your brain can not directly use fatty acids, instead those fatty acids need to be converted to ketone bodies. When you are a glucose burner your brain needs something like 140 grams of glucose to use as energy. When you stop eating carbs your brain is able to meet about 2/3 of that energy need with ketone bodies. There are many other parts of your body that can use ketones for energy, but I think that if you are maintaining a constant energy demand, your body will prefer to use fatty acids where it can, glucose where it needs it, and ketones for your brain or any extra load that you might put on your body. For example, my ketone levels stay probably around 0.5 most of the time unless I do a lot of exercise. I think David Feldman said something about how people on a ketogenic diet are actually mostly on a fatty acid diet. I hope this makes sense!


Thanks for the clarification. I knew MCT powder/oil was not ketones, but I often read about people adding MCT to get their ketone levels higher. And that confuses me, too. What’s the point of seeing a higher ketone number if you know it came from something you ingested rather than from burning your OWN body fat?

And thanks to everyone for the responses, and the link to that great article. I think I get it now. I personally love measuring my ketones (breath and blood) because it keeps me motivated, but I’m sure a few months down the road I’ll be tucking the testers away in a drawer. For now, it’s fun to watch the numbers change. (I guess I’m easily amused!) :crazy_face:

(Michael - When reality fails to meet expectations, the problem is not reality.) #7

There are health benefits to having your innards continuously bathed in β hydroxybutyrate and generally I suppose more is better than less.

(Cancer Fighting Ketovore :)) #8

For me, as a cancer patient, I want my ketones high and glucose low. To do that, I am starting to supplement with ketones. Of course, I just started an anti-cancer medication that raises my glucose… But I can always take something to lower my glucose (it’s actually commonly prescribed because high glucose is a common side effect)


Thanks, I’m grateful for the sharing of information and the ever-growing research that’s being done!