Science: What is Ketosis? Will it Help You Loose Weight?

Yes, maybe, sort of and not long term. Helpful right? So it’s all the rage right now the ketogenic diet, it revs your fat burning up and as long as you stay in ketosis the pounds will melt away. It’s high fat low carb, you pee on these weird sticks and it worked for the Inuit and the epileptic. Plus you brain can run on ketone bodies so that’s fine too. WTF?? I actually get where some of this comes from but I have a PhD in cell and molecular biology so what is the ketogenic diet all about? Here it is, all of it in terms you can understand. But… you’ll gather that it’s not something I advocate for, and it’s not. I don’t think diets in general are a great idea just eat what you should everyday starting now and you will loose weight until you get to a healthy one, that’s it. Doesn’t sell a whole lot of books does it.


What is ketosis?

What your body does generally

Ketosis is a metabolic state that a body can enter in which at least some of the energy for cells in the body comes from ketone bodies in the blood. Ketone bodies are released into the blood as an energy source when fat is burned. It is heralded as an alternative to glycolysis in which the energy comes from the breakdown of glucose (a sugar). You can also break down protein for energy.

Your body contains two main types of fat stores, subcutaneous fat (under the skin) and visceral fat (around the organs). You actually need some of both types and too much of either isn’t a good thing. But we know that a dramatic excess of visceral fat puts you at risk for all sorts of nasty things plus we tend to think it looks worse. You take in food to provide your body with the energy it needs and if you take in more than you need, which is normal to do in the short term, you ultimately store it as fat. When you don’t have enough food for your current energy needs you burn that fat for energy. But you need some fat in your body to protect yourself, your organs and fill in the spaces it’s normal and healthy to be about 25% fat for females and 20% for men. This let’s you get through lean times, protect you from times you can’t eat or absorb food like when you are ill and maintain body processes like hormone production and pregnancy, that’s why women need a bit more.

To say you body is designed to run on one of the three or runs better on one is utterly false. It is designed to run on all three, and then some. Usually the main source is glycolysis because that is basically the pay as you go system and that energy is readily available. If you have a high fat or protein meal you body can run on that too. Your body will first burn that glucose available in your blood, then glycogen in the liver and then when that runs out stored fat. In the course of a day, especially if you had a light breakfast and a late lunch or exercised hard or for a long time you might enter a ketosis heavy metabolic state. If you have a stable body wight chances are you are not storing fat very often at all or burning it, you’re largely getting by on the glucose on your blood and stored glycogen and that’s totally okay. However you might store a bit more fat, like when you’re eating well on vacation then burn some stored fat when you’re really busy and skipping the odd meal and that’s okay too. It’s even okay if you make some small changes when the jeans get a little tight.


What is ketosis

Put simply it’s a totally natural, normal state of metabolism that means at least part of your energy is coming from stored fat in the form of ketone bodies in your blood. Ketosis turns on in response to high glucagon and low insulin levels in you body. This happens when you’re running out of blood glucose so no insulin which tells your body to store blood sugar in the liver. So you’re glucagon hormone levels go up telling your liver to send glycogen out into the blood stream as glucose.  Insulin levels from when your blood sugar level is low and glucagon levels rise when your blood sugar is low to signal the release of glucose from the liver in the form of glycogen. Essentially the stored fat on your body is released in the form of fatty acids which need some modification before they can be used as energy. They are broken down into a smaller molecule called acetyl-CoA in a two step process and provides energy to your body. The acetyl-CoA then is taken to the liver where it is turned into ketone bodies which then move to the blood. These ketone bodies are what you are detecting when you use a product like ketostix is these ketone bodies in your urine. This process is reversed to store fat. The ketosis process can be triggered by diet, alcohol consumeption and exercise.

However you body doesn’t ‘pick’ it’s fuel in a straight line direct fashion. It’s not like you burn glucose, when that’s gone you move onto glycogen and when that’s gone fatty acids. Rather it’s a continuum of the three. If you waited until you ran out of all the energy from one source before moving onto the next you would likely die. I say likely because NO ONE and nothing does this. But your cells would completely run out of energy, all process would stop and then so would you. You are getting energy from these sources as needed. Lets take this as a scenario it’s just a regular day and you get up and eat breakfast (big, small, healthy unhealthy doesn’t matter) you raise your blood glucose levels and use that for energy, but you still are releasing a bit of stored glycogen from your liver and perhaps a bit of fatty acid metabolism is happening too from the overnight fast. None of these processes stop the balance just tips toward storing that glucose as glycogen and perhaps some as fatty acids. Now it’s 10 am and your blood glucose levels are a but lower, your body pulls out some of that stored glycolen as glueose and turns up the level of fatty acid metabolism a notch so your energy levels are the same and your blood glucose level is pretty stable. Now it’s 1 pm lunch time. Your mostly releasing glycogen now, maybe a good mix of ketone bodies in your blood too and this end is ‘ramped up’ a bit for the time being but as you release some glycogen into the blood as glucose a tiny bit of that is being stored too. And then you eat lunch and the cycle repeats it’s self. No process is ever fully on or off but rather the switch is above 50% for the forward or reverse reaction leading to a net direction and an overall trend between the three. So you see ‘tricking’ your body into ‘picking’ one source is impossible.

What is a ketogenic diet

It is heralded as a low carb high (healthy) fat diet. You eat foods that are high in fat and or protein and low in carbohydrates. There are a few variations like high protein or taking in carbs around workouts but that is essentially it. But as you look at the suggested diet plans they are also low calorie, like really low calorie. Most (over 80%) that I looked up added up to less than 1200 calories a day. 1200 calories a day is regarded as the cut of for starvation though no one really knows why that’s the magic number. So essentially what’s out there now as a ketogenic diet is a starvation diet that’s very high in fat and decidedly low in carbs.

Screen Shot 2018-01-25 at 11.08.17 PM
I hope you like avocados!!

Origins of the diet 

For the treatment of epilepsy there is evidence that ketogenic diets go back to ancient times and was well described in the 1920’s. I first became aware of it in the context of diabetes and ketoacisidosis. My dad was Diabetic and he occasionally used keto strips to make sure he was still safe from it. If he had a problem he would pass out and potentially enter a diabetic coma. In collage I truthfully became aware of it on a site about eating disorders. It suggests that you get some diasticks to make sure you were starving yourself effectively enough. For reasons I didn’t fully dig into a low carb diet that keeps you in mild ketosis has long been established as an effective treatment for some people with epilepsy? Weird right? So when you hear that it goes back to the 1920’s or 4000 BC this is usually the context it’s actually referring to.

Why is it having a moment right now?

There have been some crazy diet ideas out there over the years. Even though I’m too young to remember it my mom swears the cabbage soup diet was in fact a thing. I remember the apple diet, the baby food diet and the cayenne pepper lemonade cleanse. These will obviously make you loose weight but… absolutely nutty and unhealthy right! Most people see through these right away so we have to dress them up a bit. Then there was Atkins, paleo, bread belly and low carb which which are essentially all the same thing. Lower carbs replaced with higher fat foods, mainly meat. Sound familiar? In a lot of ways the ketogenic diet is just another iteration of that. The truth of the matter is that if you cut carbs from your diet you will loose a lot of weight in the very short term but carbs especially complex ones trigger our full feelings the fastest. Protein makes us feel full for longer and fats are in the moment delicious. A mix of all three is the recipe for the perfect yummy meal! So most people give up relatively quickly since they feel hungry. If you stay one this diet long term and get enough calories to eventually stop loosing weight you’ll end up like Atkins himself with heart issues.

Apparently on the Ketogenic diet you eat a lot of avocados and nuts, like A LOT!  It seems these two ingredients replace most of the meat in the Atkins and Paleo diets. In the last few years meat has been given a bad rap, possibly for good reasons. It has a high carbon and pollution footprint, it’s mean to animals and the WHO now lists it as a possible carcinogenic and last year veganisim got so much attention. So it’s the perfect time for a new low calorie, low carb and lower meat diet, enter the ketogenic diet.

What can go wrong?

For your average dieter, not really a whole lot. Here’s what I mean by that… If you are on any diet that has you consuming 900 -1100 calories a day and cutting out huge food groups you will loose a tonne of weight. But you will literally be starving, at first that’s no big deal you’re dedicated and you have lots of spare fuel on board. But pretty quickly the cravings for food, any food but especially the food you can’t have take over. You’re cranky, hungry, deprived and tiered. Then comes the binge. You might try a few more times but after a few slips, fights with family and friends (you’re in a terrible mood) and being sooo hungry all the time you give up right? No more special weird expensive food or breakfasts of eggs, cream cheese and peanut butter, what are you exactly putting the peanut butter on? But that also means that it won’t work right?

But… pushed to the extreme ketosis turns into Ketoacidosis and this can occur from either a starvation diet or staying on a ketogenic diet long term. Truthfully diabetics and alcoholics are most at risk for ketoacidosis. This is when ketone bodies build up in the blood stream to dangerous levels. A word of caution about those urine dip sicks, most only measure one of the two types of ketone bodies AND its concentration dependant. So if you are drinking a lot of fluids to fill yourself up and peeing more you might under estimate the levels of ketones in your urine. Basically so much ketone bodies from fatty acids build up in your blood that it goes beyond your bodies ability to buffer the pH of you blood, this first leads to comas and then death. The first signs is breath that smells like nail polish remover due to the build up of acetone.

Like any other extreme and basically starvation diet will lead to a limited number of people developing an eating disorder. The binges that these diets can lead to then lead to feelings of guilt and even high levels of pain from eating so much. This can lead some people to purging most commonly through vomiting or other measures. This can trigger bulimia in some people. For others the success lead to more extreme forms of dieting, then others notice which reenforces the behaviour. Some people get addicted to the feelings of being hungry and it becomes a coping mechanism for them. This leads to anorexia which leads to death in about 20% of patients. On average it takes 7 years of treatment for someone to recover from an eating disorder and relapses are always possible.

So what are you to do?

Let’s be honest here you’re looking into ketogenic diets because you have a decent amount of weight to loose. Chances are if you give it a try you will loose weight and now you are informed. In my opinion it is in fact a diet which means it is not a long term solution or a healthy lifestyle change. Diets rather than making consistent healthy choices are a short term solution to a long term problem. Check out this post on how to tell if you are on a diet that’s doomed to fail again for a more detailed conversation about that. Generally eat the number of calories you need in a day to maintain you goal weight and do the things you already know you should be doing. Things like:

  • Avoid processed food as much as possible
  • Work on getting your portion control right
  • Eat less meat and more veg
  • Get 30 minutes of activity 5 times a week
  • Avoid drinking your calories
  • Avoid eating because you’re bored, tiered or emotional
  • Watch your snacks, are they more like meals?
  • Go for whole grains whenever possible?

What is the craziest diet you’ve ever been on. Have you tried the ketogenic diet? Did it work for you?

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