Monday, May 12, 2008


Gluconeogenesis is a big word, but it's important because it's why low carbing works. Let's break it down:

gluco - glucose (a carbohydrate)

neo - new

genesis - to make

Gluconeogenesis means "to make new glucose." It's a process that happens in the liver. The liver uses a set of enzymes to take the glycerol backbone of lipids or amino acids (the building blocks of protein) and convert them to glucose. People will often tell you that you need to eat carbohydrates to be healthy. You don't. In fact, if you ate nothing but protein, your body would be able to make about 400 grams of carbohydrate every day from the amino acids in that protein. (Not recommended, of course, but it's theoretically possible.) More tomorrow.

(The picture is from the Elmhurst College Virtual Chembook by Charles E. Ophardt.)


WoodsWalker said...

Hi Stargazey,

I've just spent the last hour reading the blog archives, and I'm just delighted at your contribution to the popular understanding of certain aspects of the metabolism, and the value of a low-carb diet.

For instance, although I've tried to educate myself, it was only when reading your post on gluconeogenesis a few moments ago that I first fathomed how ingested fats become sugars for our bodies' use.

Your explanations are clear, concise, and even entertaining (and you've sourced great illustrations). Thanks again for all your posts, and I hope your blog gets a lot of traffic!

p.s., I found this blog when I Googled "low carb leptin fat metabolism", in my search for info on how a low-carb diet fosters the mobilization of fat from our cells.
p.p.s., I'm on Day 2 of doing it. Wheee!

Stargazey said...

Thank you, Woodswalker! And I wish you all the best as you begin the low-carb lifestyle. (By the way, Day 2 is the hardest. Once you're through the "Atkins flu" and have switched over to gluconeogenesis, you will be amazed at the steady improvement in how good you look and how well you feel.)

For the sharp-eyed among my readers, I should point out that only the glycerol backbone of ingested fats can be turned into glucose. The fatty acid components of triglycerides constitute the largest percentage of stored and ingested fats. Fatty acids are metabolized as two-carbon units, which means that they can be converted to energy or resynthesized into fat, but cannot be converted into glucose. For that reason, most gluconeogenesis uses glucogenic amino acids as its starting point.

Again, thanks for dropping by and thanks for your comment.

Former Donut Junkie said...

As I've said before I just love your blog. It breaks down into a language most of us can understand the 'techno-geek' sci/med terms. I'm currently studying Gluconeogenesis and remembered seeing something here about it. I found this article and it said at the bottom, "more tomorrow", but I don't be able to locate a sequel to it. If there is one could you kindly direct me to it? And any other good links you have ont he subject. Ron, aka The Former Donut Junkie.

Stargazey said...

Regarding the "more tomorrow," I think I was talking about the body's rather low requirement for carbohydrates more than about the specifics of gluconeogenesis, per se. At any rate, that's what was addressed in the 5/13/08 post of the following day.

If you'll look at my comments in the 11/24/08 post on Metformin, you will find a bunch of links that lead to additional information on gluconeogenesis. Metformin down-regulates gluconeogenesis, so that's why the subject came up in the comments. And thanks for the compliments!