Thursday, September 13, 2012

Ketosis and Blood Ketones

Nutritional ketosis is the state in which ketone bodies are produced to fuel nearly every type of cell in the human body.  This energy state occurs when humans ingest typically less than fifty grams of carbohydrate per day.  It could be surmised that if you randomly sample a single human on Earth, they will not be in ketosis, due to the high amount of processed and inexpensive food conveniently available.  In third-world populations, this is especially true due to limited food availability, poor economy, war and climate-related issues.  It is this type of food which contains high carbohydrate concentration and prevents ketosis from ever becoming a remote possibility.

Glycolysis is the human body's state where glucose, derived from any carbohydrate ingestion, is used to create energy.  This can occur from ingestion of sucrose, lactose, dextrose, galactose, or any other "ose" (simply speaking - sugar).  Generally an individual will be in glycolysis if they ingest over 50 grams of carbohydrate per day, though this may be higher or lower for some individuals.

As stated in countless articles, studies and texts, the peptide hormone insulin is kicked into action when blood-glucose levels are heightened after ingesting a meal with carbohydrate.  One of insulin's main functions is to lower blood-glucose.  It does this due to the fact that prolonged and continuously high levels of glucose in the body is toxic and can lead to future debilitating disease, coupled with cellular-insulin resistance.  Insulin also does its job of storing fat away for fuel, whether you need it or not.

Individuals who gain weight that was not a direct result of sex hormone (i.e. puberty) or genetic issue are beginning to see the result of a lifelong state of glycolysis.  Scientists, organizations and nutritionists alike will explain this is simply a result of aging and "slowing metabolism".  Fortunately, we have data that a lot of people who ate differently - some not too long ago - had very different health outcomes.  It was not until Western Diet (like that mentioned earlier) was introduced that Western Diseases were concurrently introduced to previously isolated cultures.

This "slowing metabolism" is the degrading of the body's adipose tissue's ability to properly regulate fat flow.  This tissue prefers to hold onto fat for those in glycolysis.  In ketosis, stored fat (triglyceride) actually breaks down into component fatty acids which are released into the bloodstream for fuel.  After a meal, if you compare triglyceride levels in someone in glycolysis vs. someone in ketosis - you will see the latter has a much higher level of triglyceride.  However, the body regulates this soon after the meal - while the former individual maintains a high level of triglyceride long after the meal.  This result can be seen comparing fasting lipid profiles of each individual.  Triglycerides are predictably low in KD patients, while low-fat and high carbohydrate adopters possess very high levels.  

Little known is the fact that ingestion of carbohydrate leads to lipogenesis, or the creation of fat.  Many firmly believe that eating "low fat" foods is healthy, as it equates to less fat in their bodies.  However, when you remove fat, you typically insert more carbohydrate (perhaps some protein) - which invariably leads to a much higher output of fats through lipogenesis.

Many people have found they can lose weight quite easily by simply reducing their refined carbohydrate intake, not needing to push their bodies into a state of ketosis.  Yet, dependent upon the specific goals of the individual, keto-adapting may be an individual's best bet for losing the most weight and having a much better rate of diet retention.  Most of the cause for this higher success rate has been shown to be:  greater satiety; no calorie limit; no hunger pangs and speedy weight loss.

When the body is in a state of ketosis, triglycerides are broken down into their component fatty acids for fuel.  The liver is busy churning out ketone bodies. 

Previously, one could check whether they were in a state of ketosis via the guidance of ketostix, as mentioned in my July post.  However, this tests urinary ketone levels.  This is not a very effective way to check for ketosis for a few reasons.  The main strike against it is that some individuals may never pass ketones in the urine.  Others may pass them only at certain times...or in limited amounts.  This type of information can mislead an individual to believe they are not in ketosis. 

Using a ketone meter to instantly check blood ketone levels is currently the best method for testing whether one is in ketosis.  As the aforementioned post also stated, there are a specific range of blood ketone levels associated with nutritional ketosis.  Naturally, people begin to wonder - what 'level' they are at currently.  Furthermore, what does it matter?

Tom Naughton, of Fat Head fame, claimed on his blog that regarding Jimmy Moore's plight to start losing weight again, it was not until his blood ketone levels went from 0.1 to 2.0 that he began to lose weight.  He also mentions that some individuals are "...hyper-responders to insulin-producing foods, staying in ketosis may be the key."

Dr. Andreas Eenfeldt AKA "The Diet Doctor" has a recent blog post claiming he's performing a N=1 experiment on fat loss by testing blood ketones.  It seems like a lot of us have these new toys.  But, the word is still out on whether a higher level of ketone bodies equates to an increased efficiency in fat burning. 

Gary Taubes has been nice enough to take the time to answer some of my deepest, darkest questions recently.  Gary stated that he was not aware of any correlation between blood ketone levels and fat loss, though he thinks there would be.  Of course, he like I would prefer to have the facts.  Hopefully he'll get some as the NuSI was just launched yesterday!

A recent "Ask the Experts" Jimmy Moore podcast hosted Dr. Stephen Phinney.  I was lucky enough to have him answer one of my questions:

"Do higher levels of ketosis mean you will experience more rapid weight loss? I’ve been measuring my blood ketones and wondered if readings over 2.0 millimolar meant that I was in the ideal range for optimal fat loss."

His responses (around 1:06) "...being in ketosis doesn't guarantee weight loss...being in ketosis facilitates fuel flow."  He goes on to say how nutrient ratio is more key to the reduction of fat.

(around 1:08)  "There is nothing about having a specific blood ketone level that guarantees weight loss.  What that does guarantee you is excellent fuel flow.  So if you can then use that fuel flow by either cutting back modestly on total amount of calories eaten or as in my case upping amount of calories expended....[you will then begin to see the change]"  He goes on to say he and Dr. Jeff Volek are looking into ketone variance between individuals - the variance is significant.  Should know more on that within a year.

As far as scientific data, it looks like the question is definitely still out there on blood ketone levels and their affects on many health aspects.  Hopefully we'll get some solid information from the aforementioned doctors and initiatives.