Are Keto Diets healthy or harmful? Well know, that depends…
What are Ketone Bodies?
The body has two sources of fuel to use for metabolic processes: sugars and fats. Those can be both dietary sugars and fats, or stored forms of the same—glycogen and body fat.
Some excess dietary sugar gets stored as glycogen in the liver and muscle. Glycogen stores provide quick energy and are used in fight-flight responses, high intensity exercise or stressful situations.
Excess dietary fat storage gets used as energy or stored as, well, body fat. Actually, blood sugar, in excess of what is needed to fill glycogen stores or to use for energy needs, also gets stored as fat. Here’s why…
Insulin is a storage hormone. Its job is to keep the blood sugar levels within a normal range. When insulin is released, triggered by increasing blood glucose levels, that insulin opens the gates of the cells in different tissues of the body, so that sugar can go from the blood, into the cells, thereby lowering blood glucose concentration. When those cells have accepted all they can, the sugar is then taken to the liver where it is converted to fat which is then stored in fat cells all over the body. This fat can be stored in fat cells in and around organs like the liver which is one of the causes of fatty liver disease.
So, insulin is released from the pancreas when blood sugar goes up. What causes the blood sugar to increase?
- Eating foods, like grains and processed foods, that turn to sugar in the intestines. That sugar is then absorbed into the blood stream,
- Eating too many starchy carbs and fats together,
- Eating too much protein at one seating,
- Eating too many calories at one seating.
Glucagon is the balancing hormone to insulin. Glucagon is stimulated to go up as insulin and blood sugar levels come down. When dietary sources of carbohydrate that cause high blood sugar are lowered, blood sugar goes down and glucagon is released.
Glucagon takes stored energy in the form of glycogen and fat and mobilizes it into a usable form of energy for the body’s tissues and cells. Ketone bodies (or ketones) are a result of the stored fat being mobilized by glycogen. They are the usable source of energy that is now available in the absence of high blood sugar levels. They are NOT poison, as I heard one health guru state. They are simply a source of energy—and a very clean and efficient source, at that. More on that later.
The Ultimate Goal in a Keto-Diet
The short-term purpose of going into ketosis is to mobilize stored fat. As long as blood sugar remains high enough to cause insulin to be released from the pancreas, any excess energy will continue to be stored as fat. No question—it’s how that system was designed to function. A person gets into ketosis (i.e. burns body fat) by manipulating their dietary choices so that insulin stays low (which stops the storage of energy as fat), and glucagon increases (which increases the mobilization of energy).
So, really, we can say that we want to eat in order to keep insulin low and glucagon high. That means that we have to eat foods that don’t raise blood sugar.
Not Your Mother’s (or Grandmother’s) Adkins Diet
Initially, a person can get into ketosis by eating a high protein/high fat/low carb diet like the Adkins Diet. At this point, the key to keep insulin low and glucagon high is the low carb part. The more weight a person has to lose, the longer it will be until they hit a plateau. But that plateau will come and here is what I believe to be the reason:
When a high protein diet is first initiated, the total calories from over-all fat, both stored in the body and dietary, exceed the total dietary protein. Since the body will always use fat before it uses protein for energy, it is happy with the ratio of more fat than protein. But as the body stores of fat begin to decrease, that ratio changes. When there begins to be much more overall protein than overall fat, the body switches to using protein for its energy source. In order for that to happen, protein must be taken to the liver where it is metabolized into sugar by a process called gluconeogenesis. That sugar is then released into the blood, causing insulin to increase again, and fat loss to stop.
So, a high protein diet (even if it’s low carb) can eventually cause rising blood sugar levels, which is contrary to what we want to happen. If you’re on a high-protein keto diet, and you’ve hit a plateau, or if you monitor blood glucose with a meter because you have a history of diabetes, then evaluating your protein consumption is essential to your continued success.
Protein is also an issue because high consumption is clearly linked to some cancers—moderating genes like mTOR.
So, an unhealthy version of the Keto Diet is one that is high in protein. Since there are only 3 macronutrients to choose from: fats, protein, carbohydrate, and we’re already trying to keep net carbs low, then the only source left is fats. In truth, carbs can be eaten plentifully, they just need to be from the right sources. See the post on Carbohydrates and Keto Diets: The Good and The Bad for a more in-depth discussion on that.
The Healthy Version
The healthiest version of a Keto Diet is one that is low to moderate in protein consumption, high in healthy fats, and HIGH in non-grain/non-starchy plant carbohydrates.
This type of a Keto Diet gives you all the anti-inflammatory benefits of low blood-sugar AND all the powerful healing benefits of non-grain plant-based vegetables, herbs, and spices, without the potential problems of a high protein diet.
When Keto is done in this way, it doesn’t just decrease your weight, it decreases your risk of ALL diseases. Win, win, win. We all win.