The Vicious Cycle of Diabetic Ketoacidosis
Diabetic Ketoacidosis is a familiar term to most T1 diabetics. The only populations at practical risk for Diabetic Ketoacidosis are either T1 diabetics or T2 diabetics whose condition has advanced to the point that their pancreas’ ability to produce insulin is greatly impaired.
This is the second of a three part post on the subject of ketones. The first, Ketone Danger: “Are ketones dangerous to diabetics?”, examined the history leading to the myth that the mere presence of ketones in the blood or urine is dangerous. In this post, I’m going to go into a little technical detail regarding the specific biological conditions that lead to Diabetic Ketoacidosis, in order to contrast that state with the perfectly normal state of Nutritional Ketosis, which I will follow up on in my next post.
In my own personal experience, while I have never been diagnosed as having the condition, I have come dangerously close on a couple of occasions, neither of which are related to my diet, but rather poor preparation. Both incidents bear closer examination, which I will do in future posts. I continually have a measurable amount of ketones in my blood stream, however, because I subscribe to the health benefits of the ketogenic diet.
The Delicate Dance of Insulin, Glucagon and Fatty Acids
Insulin and glucagon are two hormones produced by your pancreas that play roles in maintaining your blood sugar at healthy levels. You are no doubt aware that insulin is the “key” hormone that allows glucose to pass from your blood through your cell walls in order to give you energy. You might not know that the release of insulin from your pancreatic beta cells also inhibits the alpha cells in your pancreas from secreting glucagon – the hormone that causes your liver to convert its stored energy into glucose and prevent your blood sugar from dropping too low.
Insulin’s inhibition of glucagon is necessary because blood sugars in excess of the normal range for any extended length of time has toxic effects on your body and the effects of glucagon at the same time that your body needs to produce insulin would be counter-productive. Since the presence of insulin presupposes higher than normal blood sugar, it negates the need for your pancreas to release glucagon and liver to express glucose.
After your previous meal or snack has digested, your blood sugars have returned to normal and the last bolus of insulin has almost entirely been filtered from circulation, your pancreas can release glucagon. Your body is now in a glucose sparing mode, trying to keep just enough glucose in circulation to feed the minority of organs in the brain that absolutely depend on glucose for fuel, and to have enough reserve glucose swimming around for instant energy needs.
When your blood sugar is high, your body prioritizes its use for fuel, simply because it will gunk up the works if allowed to remain high. When your blood sugar returns to normal levels, you don’t have much insulin on board and you need to preserve glucose levels, your body’s metabolism is free to switch gears and starts to release fatty acids from your fat cells to provide you with energy. Conveniently, insulin also plays role in preventing the release of fatty acids from fat cells. Like a finely tuned switch, the degree to which insulin is absent in the blood stream determines exactly how much free fatty acids your fat cells release into circulation (and thus, how quickly you lose weight, but that is a topic for another post).
The Vicious Diabetic Ketoacidosis Cycle
Diabetic Ketoacidosis is caused by levels of insulin in the bloodstream getting too low to satisfy even the most minimal needs for glucose metabolism. During periods of too little or no insulin in the blood stream, a cascade of compensatory events then occur and begin a self-reinforcing cycle, continually increasing the blood’s acidity at a rapid pace.
- The body misinterprets the lack of glucose inside the cells as a lack of glucose in the blood… even though there is likely already unhealthy levels in circulation. Thus it releases glucagon to signal the release of even more sugar stores from the liver, the concentration of sugar in the blood stream rises even more.
- There is no more insulin to keep fatty acids locked away in fat cells, so they are getting released in unhealthy, upwardly spiraling amounts.
- The liver is happy to multitask, and while it is busy converting its glycogen and proteins into glucose at the behest of the glucagon in circulation, it is also converting all of these extra fatty acids into acidic ketone bodies at a rate that begins to alter the pH (acid/alkaline balance) levels of your blood stream.
A quick refresher on acid/alkaline balance. The pH scale goes from 1 to 14, where 1 represents the maximum possible acidity of a substance, and 14 represents the maximum possible alkalinity. Thus, a pH of 7 is perfectly neutral. The human body runs optimally at a slightly alkaline value of 7.4. Deviate even a few of decimal points from this value, and you will likely go unconscious and be unable to take any actions to stop the metabolic cycle from feeding on itself and driving even further out of control.
The increasing amounts of acids in circulation would quickly change the pH of your blood were it not for the fact that your body has compensatory mechanisms for reducing that acidity. When the balance deviates at all from a pH of 7.4 your body calls up the National Guard, in the form of electrolytes that normally have a day job inside your cells doing other useful work.
Phosphorus, potassium, calcium and other minerals all leave their responsibilities of driving your body’s energy metabolism and keeping your bones strong to instead flood into the bloodstream where their alkaline properties can counter-balance the increasing acidity of the ketones in your blood and bring it back to a nice, comfortable level. As the acidity levels get higher your nervous system will even make you start hyperventilating in an effort to clear the carbon dioxide (which is itself slightly acidic) from the blood.
Now your blood stream is getting increasingly overrun with acidic ketones, too much glucose, and alkaline electrolytes that should be inside your cells doing other work. As this soup approaches toxic levels, your kidneys come to the rescue by filtering it all out into your urine as quickly as possible, and serving you up a powerful thirst. Before you go saying, “Yay, Kidney Twins!” realize that this doesn’t help matters as much as you wish that it would, because with urine, so goes the water in your blood stream and thus the total volume of liquid in your veins.
This loss of blood volume is an important point in this deranged cycle. You may have noticed that your blood sugar and ketone levels are measured in milligrams per decaliter (mg/dL) and millimols per liter (mmol/L) respectively. Decaliters and liters are measurements of liquid volume. So mg/dL or mmol/L is a measure of amounts of glucose or ketones per a unit of your blood’s volume expressed in multiples of liters.
Why does blood volume make a difference? Well, back in the liver, the production of ketones and glucose doesn’t let up, but now both concerns are dumped into a volume of blood which is getting lower as fast as your bladder is filling. As the volume of your blood goes down, and the measure of glucose and ketones in circulation go up, your blood sugar and ketone ratios (and hence your blood’s acidity) increase at a frighteningly dangerous rate. More circulatory pollutants, more overworked kidneys, more dehydration, still lower blood volume, more acidity, more electrolytes pulled from duty to bring your pH level back up.
Rinse. Spin. Repeat…
Now you may be thinking that the acidity in your blood is eating you away from the inside, and that’s what kills you, but what actually starts shutting things down is the fact that:
- Too many electrolytes have left their respective and vital day jobs inside your cells, disrupting their sensitive homeostasis, and your cells begin to either rupture or shut down for lack of a means of processing fuel.
- The aforementioned ruptured cells deposit a protein called myoglobin, and creatinine into circulation. This further increases the load on the kidneys, possibly leading to kidney failure, certainly leading to still lower blood volume.
- High levels of phosphate in circulation (a condition called hyperphosphatemia) interfere with the ability of your red blood cells to both adhere to and transfer oxygen to cells which need them for energy.
- More solid contaminates of all the varieties mentioned, coupled with less liquid, lowers the ability of the blood to circulate at all in the smaller vessels, and carry oxygen and nutrients the last mile to the cells.
- Astronomically high blood sugars contribute to a disruption of the blood vessels’ osmolarity – that is to say, the direction that fluid travels into or out of them – and leads to brain swelling (Cerebral Edema) or the lungs filling with fluid and further decreased availability of oxygen in the blood (Adult Respiratory Distress Syndrome).
Essentially, there is a large disruption to your body’s homeostasis, sufficient cell starvation and death occurs, chemical processes and then entire vital systems are thrown out of whack. When your internal organs eventually reach a tipping point where they don’t have any more resources to give, they begin shutting down.
Hello, coma.
Hello, Grim Reaper.
Why Should You Care?
I don’t know about you, but I’ve read dozens of books about eating a ketogenic diet, from The New Atkins by Dr. Westman for weight-loss; to Ketogenic Diets by Drs. Kossoff, Freeman Turner and Rubenstein, principally dedicated to the treatment of epilepsy; to The Art and Science of Low Carbohydrate Performance by Drs. Volek and Phinney, dedicated to using a ketogenic diet to enhance sports performance. In each of these resources, and several in between, they are careful to make the distinction that the level of ketones targeted in each of their approaches amount to a benign physiological state now popularly known as “Nutritional Ketosis”.
Every one of the books on the subject that I have come across, cautions, as Dr Peter Atia puts it, “DKA [Diabetic Ketoacidosis] and Nutritional Ketosis have as much in common as a house fire and a fireplace.” …and that you only need to worry about Diabetic Ketoacidosis if you are a Type 1 or very advanced Type 2 diabetic.
We will go into detail about Nutritional Ketosis in the next post, but for the purposes of this post, I wanted to address questions of safety, since you are most likely reading this because you are in one of the two above mentioned groups, or are the parent of such a person and have concerns.
Children: Diabetic Ketoacidosis: Ketogenic Diets
Right up front, I want to caution you that a ketogenic diet as a strategy for caring for T1 Diabetes Mellitus is a personal choice to be made by an informed adult. It is not a choice that you foist on someone else, especially if you are making choices for someone with diminished capacity to monitor themselves and make informed decisions.
Particularly if you are the parent of a child with diabetes, you know how terrifying it can be wondering if your child has gotten annoyed with his or her insulin pump and removed it for a sports activity or just feelings of rebellion from the disease and forgetting to reactivate it. There is also a phycological condition known as diabulimia, where diabetics manipulate their basals and boluses in an effort to lose weight… a strategy that is particularly tempting to adolescent T1s who are trying to conform to the unrealistic body image standards of our society.
As a parent, you can monitor only a very narrow window on what is going on in that child’s body. So while I am thoroughly on the side of medical science in telling you that Nutritional Ketosis is not Diabetic Ketoacidosis, and the former does not lead to the latter, I feel that it is too complicated, with too much at stake to feel comfortable recommending the use of a ketogenic diet to manage someone else’s diabetes.
This is not to say that this blog is worthless to you as a parent of a diabetic child. If you continue reading, I hope that you will be relieved to learn more about the nature of the disease, resources that I offer for lowering sugar spikes, and monitoring and maintaining health as a T1 during extreme exercise.
Let’s Stay Safe Out There!
The specific conditions required to start up the not so merry-go-round, metabolic spiral of Diabetic Ketoacidosis are:
- A lack of sufficient insulin to…
- …provide for one’s minimal glucose energy requirements.
- …moderate the release of glucagon.
- …moderate fatty acid release from fat tissue.
- There is no condition 2! Everything else that is harmful in DKA is a result of a lack of sufficient insulin.
If you are a T1 striving to keep your blood sugars down within the same range as your non-diabetic friends (hovering around 80, with occasional postprandial peaks around 140), then you are as safe as any well controlled diabetic, regardless of the diet you are eating. I’d like to think that being in a state where your body is adapted to using ketones for energy needs acts as a buffer for DKA, but that is scientifically untested to the best of my knowledge, so it would be irresponsible to make that claim. You still risk DKA if your cannula from your pump gets obstructed or falls out in the middle of the night, or if you remove it for an activity and forget to reattach. You still risk DKA if you neglect or forget to take your basal if you are on a needle. These realities don’t change.
I want to urge special caution regarding one aspect of the ketogenic diet. If you go down this road, you will likely read many references to ketogenic diets and weight-loss. It is the perspective from which most of the books and articles about the diet are written. It is a perspective that does not bear in mind the consideration that one needs to monitor him or herself for the symptoms of Diabetic Ketoacidosis. These priorities do not serve you as a T1 diabetic.
Diabulimia, isn’t just a problem for adolescents and young adults… any of us experiencing the middle age spare tire can be tempted to run our blood sugars a little high in an effort to shed a pound or two. No, Nutritional Ketosis is not Diabetic Ketoacidosis, but you can push yourself over the edge if your focus in manipulating your ketone levels is on weight loss instead of blood sugar control.
If you get obsessed with beating your record for “The least amount of insulin taken in a 24 hour period” (as if that means anything about how well you are caring for yourself) and let your sugar creep up into the 200’s because you are not taking sufficient insulin, then you are voluntarily putting yourself in harms way.
Do.
Not.
Get.
Obsessed.
With.
Weight-loss!
Control your blood sugars. If you are running high, take more insulin and stay hydrated. End of message.