There is a great number of descriptions online, from qualified professionals who are better able to relate the facts than I. The below signposts a few of these, plus gives my own interpretation of the basics.
I am a lay-person. All I can do is relate the basics from my own personal perspective and reading. I preclude the below with the statement that I have no medical or scientific training. This explanation reflects my own understanding. If I am wrong on any of the below, then readers’ corrections will improve my own knowledge and be gratefully received!
Here we go…
The human body can burn energy from two sources: glucose or fat. Easy thus far.
The modern Western diet revolves mainly around glucose in the form of carbohydrate. Just think of your supermarket basics: bread, pasta, flour, rice, potatoes (root vegetables) and sugar! Surprising amounts of supermarket-space is dedicated to the sale of sugar in some form or other. Whole aisles of biscuits, cakes & sweets; all available in fresh, long-life and frozen forms.
From a retail-perspective, glucose is readily available. Our bodies feel no different!
Our bodies will always metabolise glucose over fat. It is our ‘quick fix’ to energy and gives us a pleasing blood-sugar rush. The glucose then rapidly depletes and leaves us craving more. We have rapidly become a species of sugar-junkies, on a roller-coaster ride of high blood-sugar then dramatic sugar-crashes (which equally leave us feeling like crash-victims).
Unless you are diabetic, our bodies’ mechanism of dealing with this glucose is insulin (type 1 diabetics stop producing it, type 2 diabetics need a little help to get it working). Insulin is a hormone, produced in the pancreas, which concerns us here in two main ways:
- Insulin promotes the absorption of glucose from the blood to our muscles
- Insulin is the hormone which promotes fat storage
In a nutshell, insulin enables the conversion of food into energy, and stores away what energy we do not use in the form of fat. So, if we consume more calorific energy than our bodies can burn, it all goes to fat. Nutshell no.2 – that has always been my own personal problem.
So logic implies, if we lower our insulin levels, our bodies will not store fat. I like the sound of that. But how can we do this?This takes us back to carbs.
One of the added bonuses of researching this subject, is that it is continually stretching my vocabulary. I have recently learnt a new word (which I love) – secretagogue! A secretagogue is a substance that causes another substance to be secreted / produced. Why am I boring you with my own vocabulary acquisition? The primary secretagogue of insulin is dietary carbohydrate. It we restrict our carbs, we restrict our insulin. We then do not store fat!
But if we cut out the foods which provide our main source of fuel, from where do we then get our energy? Our bodies switch over from a glucose-metabolism to a fat-metabolism. Yes, that’s right, we start burning body fat!
When we burn fat, we do not literally burn it like a candle; a little processing still needs to happen. Our liver produces ketone bodies from fatty acids. These ketones are what the body uses as energy in place of glucose.
Next tedious linguistic fact – the word ‘ketone’ comes from old German ‘Aketon’, meaning acetone. When the body burns ketones this can be detected on the breath in the form of acetone (a slight smell of nail-polish remover for some). Excess ketones are also excreted in urine, but I have no flashy jargon for that.
We now link back to the title of this blog ‘Country Walks in Ketosis’. When we restrict carbohydrate-intake sufficiently to promote production of ketones, we are in a state of ‘ketosis’. At this point we have switched our metabolism from one which burns glucose into a fat-burning machine! We lose weight and climb off the glucose roller-coaster of unstable blood-sugars.
My own journey to a ‘slimmer, healthier’ me is harnessing this process in the form of the ketogenic diet.
Sites like Wikipedia and a number of LCHF / paleo websites form a great place to learn more about this process.
That’s all for now. More on the subject later. Thank you for reading,