How does the ketogenic diet work?
The low carb diet has been subject to controversy since it became a mainstream thing the last 10 years. Even though scientific studies prove that reducing calories is just as effective for weight loss in the long run, going low carb with high fat, will drastically reduce your weight within a shorter period of time. I hypothesize that this even works even though you increase total calorie intake. Why? Is it likely that you eat less, but stay satieted for longer? Many report that they eat more than they used to, and still loose weight. I think this is because you don’t have need to store extra energy when in ketosis, and the surplus burns of through metabolism increase.
First a simple lay-mans explanation about how the glucose metabolism work. I’m not a doctor or nutritionist, but luckily this knowlegde is availiable for everyone:
When eating high (normal) karb food, our bodies break down the energy quite fast, this releases glucose in the bloodstream, which triggers release of Insulin. Insulin opens our cells for glucose storage, and thus lower the glucose levels in our blood. In normal/low activity, this glucose is partly used, partly stored for future use in muscles and liver. If muscles and liver is full, the surplus gets converted to fat. This is what fitness guides refer to as “The spillover effect”. If engaged in high activity, our muscles utilize stored and circulating glucose directly, and when the glucose levels go down, the liver releases glucose until it is empty. Long before this happens, the low blood sugar and empty stomach will trigger hunger signals — and you become hungry again. The last trick in the glucose system happens when the liver generate glucose through neoglukogenesis — broken down from protein.
After that, sweet cravings, hunger, and withdrawal symptoms — until you can put your teeth in that next lovely sugar-bun.
Mostly all of us live our lives within this loop. And we digest more carbs than our bodies can utilize in a short period of time, thus we tend to store more than we manage to burn off. When glucose go low, our brains send craving signals and we get hungry even though we are chock full of energy (fat) that we cannot access. Why is that? Because our brain thinks we are starving when glucose gets low, and starts a series of signals to make us eat again. Those with the disiplin or knowlegde, can access the fat cells if they wait. This is also called “fasting”.
Most of us live like this, without knowing that our insulin sensitivity adjusts, so much so that we become more and more insensitive to our own insulin. Finally one might be at the brink of socalled “metabolic syndrome”, the precursor to diabetes type 2. The famous author and pediatrician, Robert Lustig, calls this “The epidemic of processed food”.
This shifts if you cut out all carbs from the diet. Remember, the body will utilize the energy that is easiest to get to which is glucose. When glucose is empty in the muscles and liver, it breaks down protein to create the new glucose it needs. But it can run primarily on fat, both thorugh meals, and from the stores on our body. On a High fat low carb diet, the fat gets converted into ketones, which feeds the brain and the muscles in the absence of glucose. The results are freedom from cravings, increased mood, better and more stable energy levels, and weight loss.
It is widely believed that lowcarb/ ketogenic diets work because it keeps the stomach fuller for longer, which makes us eat less. Thus, creating a caloric deficit. But In my experience i increased my calorie intake by 25% on average through a 3 months time, and still lost 10 kg of weight. Others have said “they can eat as much as they want” and still lose weight. How can it happen?
My theory is this:
When you are in ketosis and you have a surplus of fat and protein digested: Your activity level are “normal”, your liver produce the glucose it needs from the protein, but will use fat as the primary energy source. When you work out, your energy use will increase, and the body will have to ramp up metabolism and use its own storages at the same time as it uses energy from the ingested food. This is because the ingested fat and the stored fat are equally availiable as energy so the body don’t separate between them. Therefore you will use your own fat as fuel, and loose weight. But how can it work if one eats more than “normal”? I believe that the surplus of energy gets burned through increased metabolism. This is why we feel the warmer hands and feet, the more awake head and so on.
Your body will be in a state where it must produce the extra energy needed for extra work, instead of continously storing away extra energy. It is reasonable to recognize this as the “natural state”.
As mentioned by authors like Gary Taube, in evolutionary terms, it is quite logical that are bodies are adjusted to work like this. Remember that it is just in the last 100 years or so, that humans have become used to eat full meals three or more times a day. Our ancestors went long periods without food, and when they killed an animal or gathered whatever they could eat, they ate alot, since it could be a long time for the next meal. The most nutritios meal was meat and fat from other animals. Eating carbs are in evolutionary terms, a grossly ineffective strategy, since you need to refuel very often, and the carbs were not as avaliable as they are today. Looking at the animal kingdom, we see that apes become overweight when they are given unlimited access to fruit like bananas, and bears feast on berrys and honey for short periods of time, to crank up their fat storages for the winter. For humans, fast carbs through ripe sweet tasting fruits has been a luxury only avaliable for short periods through the year. It makes sense then, that the rest of the year our bodies have to run on something else. That “else” is meat and fat, which is many times more energy rich and nutritional than any vegetable. Does it mean we shouldn’t eat vegetables? Absolutely not. Vegetables might be extra beneficial for us if combined with meat, but they were never a big part of our ancestors diet. However, it seems there are big individual differences in how our bodies tacle carbs, some can eat whatever they want. But as the statistics show, most people in the western world doesn’t handle carbs very well. They get trapped in the sugar/insulin spiral that leads to craving and hunger, even though their bodies are chock full of fuel that are inaccessible, since the brain thinks its body is starving without the constant flow of glukose.
Ketogenic diet / low carb is the natural state, and must be the solution to the worlds overweight/diabetes epidemic.
