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Ketosis – Are you “Looking for Purple”?

Ketosis measured by Ketostix
"Ketonuria" by Colin - Own work. Licensed under Public Domain via Wikimedia Commons - http://commons.wikimedia.org/wiki/File:Ketonuria.jpg#/media/File:Ketonuria.jpg

Two questions I’m asked a great deal are about ketosis.
“What colour am I aiming at on the “Ketostix (TM)” testing strips? Where do I get them?”

My answers are always this:

“Benign Dietary Ketosis” as a concept was championed by Dr Robert Atkins when he published the first version of his plan in 1972. He mentions that you should measure your excreted ketones via urinalysis and be looking for a purple result.

Where to get Ketone Urinalysis sticks

Either, via Amazon (pretty much the easiest option) or at the Pharmacy counter of any dispensing Chemist. They are a “P” grade medicine, so you have to ask for them.

However, being in ketosis is like being pregnant. You either are, or you aren’t. The colour is irrelevant, any shade of Pink/Purple will do.

In fact, purple may well be a sign that you are pushing too hard. You may be eating too few vegetable based carbs. Purple means that you are dumping a great deal of excess ketones into urine, rather than burning them. If you are “purple” but find that you are not dropping fat, your body may well be fighting against your mind’s want to drop your excess fat. Your body wants to preserve its homoeostasis and keep you alive.

What are the signs of Ketosis?

If you are following Dr Atkins’ plan and so testing regularly, the preferable colour really is a pale pink. This is an indicator that your body is in its optimum fat burning zone, using everything that you are producing and not dumping any excess.

Once you are effectively burning body fat, most people can tell they are “in ketosis” by the slightly metallic taste in their mouths. Some people say that their body odour changes (Not a BO odour, just personal smell) to incorporate metallic tinges. Others report that their urine has a more noticeable “healthy pee” smell. (Foul smelling urine is a sign of a UTI, go see a doctor immediately.)

However, there is another factor to consider about ketosis,

and it may well make you want to just save your money and not test at all!

Your body make two main ketone bodies. “Acetoacetic acid”and “Beta-Hydroxybutyric acid” (HBA).  If it is not used as fuel, Acetoacetic acid spontaneously breaks down to form Acetone.

Acetone is a waste product, it must be excreted. It cannot be converted back into anything useful. Acetone is the compound which gives the faint, but distinct “sweet and fruity” smell on ones breath.

Ketostix and other testing sticks are not cheap, and they only detect Acetoacetic acid and Acetone. However, these make up less than one fifth of the ketone bodies produced when a body is effectively burning fat.

HBA goes totally undetected by testing sticks. Many people never produce enough Acetoacetic acid to cause these sticks to turn pink/purple.

If you were to have your blood drawn however, you would have plenty of HBA kicking around in there. With a blood monitor, showing all three ketone type, a reading between 0.5 and 3.0 mmol/l is the indicator for nutritional ketosis.

This means that, whilst it may be interesting to use urinalysis as an initial check, it will have nothing to do with your rate of body fat reduction.

Is it worth testing at all?

I personally don’t think that Dr A did himself or us any favours by saying that you are aiming for Purple. My opinion is that he popped the testing in there to give a “rapid indicator result” support crutch to the people that want and need those fast result type indicators.

The body converts fat into ketones and burns these as fuel in preference to glucose right up to “100g of non-processed carbs a day” for most people. However, for most people, it will only show ketones in urine at very low carb intake levels. (i.e. the Atkins’ 20g induction level)

Insulin sensitivity can become increased by holding carbs at the 20g mark long-term. So much so that raising carb levels again can become problematic.

In my opinion, just eat right and save your money.

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