Weight loss is primarily a function of metabolism and has almost nothing to do with exercise.
Of course, exercising has major health benefits and everyone should be moving their body every day as part of a healthy lifestyle. The point of this post is to explain why doing a bunch of exercise without shifting the diet to optimize for fat metabolism, is going to be a big waste of time.
The Classic Theory on Weight Loss Completely Ignores our Hormones.
The classic theory for losing weight is based on a simple formula. We’ve been told that if we want to lose weight then we have to eat less calories and burn more calories. This makes sense at first glance, but this over simplified model completely ignores the sources of those calories and their metabolic effects.
Think of the body like a house and think about calories like house guests. Different guests are going to do different things in our house. Some guests are great. They wash our dishes and thank us when they depart for being wonderful and gracious hosts. Other guests are not as charming. They make a mess and leave the toilet seat up even though we asked them to put it down 10 times.
The calories we eat have different effects on our bodies in the same way. When we eat sugars and carbohydrates a particular series of biological events takes place that is totally different from what happens when we consume fats.
I’m ignoring proteins in this comparison because proteins are typically not converted into energy. Rather, they are broken down into amino acids, which are like building blocks for the body. Cells use these building blocks to build new proteins, and in fact, eating too much protein can have a negative effect, because excess dietary protein is turned into glucose by the body.
Carbohydrates and sugars are quickly converted into glucose once ingested and subsequently released into the bloodstream. Whenever new glucose is introduced into the bloodstream the pancreas releases a hormone called insulin. Insulin tells the body to do two different things. First, it tells cells to absorb glucose and metabolize that glucose into energy (ATP). Second, it tells the body to store any excess glucose as body fat.
The hormonal response when we eat calories coming from fat is totally different. If we eat a meal coming mostly from fat, blood sugar is going to fall. When blood sugar starts to fall under a certain level–and the body regulates these levels very tightly–a different hormone called glucagon is released. Glucagon responds by telling our liver to release stored glucose in small amounts in order to keep our blood sugar at an optimal level. What is more interesting is that glucagon also sends a signal for cells to start metabolizing fat for energy. So in other words, eating fatty foods tells our body to burn fat, not to store it.
Why Exercise Doesn’t Necessarily Equate to fat Loss.
I could run on the treadmill for hours, but if my body is burning glucose to give me that energy, then I am not burning fat. This is why burning calories does not equate to losing weight. It matters what we’re actually burning, meaning what is the actual fuel that our body is metabolizing for energy. If it’s glucose then the body is releasing insulin, which means glucagon–the hormone that says, “burn fat”–is being suppressed. The typical advice, “Eat less, exercise more” is given without any consideration to hormones. It might work initially for the simple fact that eating less calories typically means eating less sugars and carbs, but the problem with this approach is that it isn’t sustainable.
Why low Calorie Diets Usually Fail.
Low Calorie diets usually don’t work in the long term and such diets are akin to lopsided football game. On one team is our willpower and on the other team is our hormones. Team Hormones is comparable to the NFL’s Super Bowl Champs and Team Willpower is equivalent to a high school football team. No matter how strong our willpower is, our biological signals are usually way stronger.
Going low calorie might work initially, but eventually most people’s willpower is no match for the hormones that regulate hunger. A specific hormone called Leptin is especially important in this. Leptin is supposed to signal the brain when we are full and satisfied. Leptin is produced in fat cells and the more fat stored in these cells, the more leptin they release. When fat cells release leptin they’re telling the brain, “Okay, we have enough stored energy here, stop eating.”
The reason that people who are overweight tend to also struggle with hunger cravings is because over time they become resistant to leptin. Here’s how it works. Imagine trying to sleep and there’s a bunch of noise going on outside. Most people would try to cover their ears because they don’t want to hear the noise. Brain cells react to long term leptin exposure in the same way by “covering their ears”. They begin to deactivate leptin receptors on their cellular membranes because for the cell, too much of one specific hormone is like loud noise.
This phenomena of cells “covering their ears” occurs with all hormones. It is one of the body’s many way of self regulation; a perpetual effort to maintain homeostasis. So over time the brain will stop hearing the “I’m full and satisfied” signal, which leads to hunger cravings. So it actually makes sense to say that people don't get fat because they overeat, people overeat because they are fat.
Food cravings in general also stem from reward centers in the brain. When people who are experiencing hunger cravings have their brains looked at with modern technology, the same brain areas show activity that mediate addiction for drugs like heroin or cocaine. Chemicals including dopamine are released when glucose reaches the brain and we can actually become addicted to this release.
I will state the obvious at this point and say that no one likes to be hungry. This is where the term hangry comes from. Maybe you’ve never experienced this or haven’t heard the term, but hangry means being so hungry that you get angry. This type of hunger doesn’t necessarily have to lead to anger–although the term is funny–and can also be characterized as a need eat. Most of us have been there, that feeling that dramatically says, “If I don’t eat something right now, I’m going to die.” Seriously, who wants to be on a diet that makes them feel like that?
There is another type of hunger which could be called healthy hunger. It’s the feeling that says, “Yeah, I could eat”. This is way different because it is not a biological craving to eat, but a knowing that some food would be good right now. “Yeah, I could eat” also means one very important thing and that is that our body has switched over to fat metabolism. Our blood sugar is stable, and we’re running on stored fat for energy.
“I need to eat” means our blood sugar is crashing and we need to restore glucose ASAP or there are going to be big problems. Honestly, when considering the consequences of a blood sugar crash the thought, “I’m going to die” is not that ridiculous.
A hungry person who weighs 400 pounds is something like an oil tanker that has run out of fuel on the highway. They’re sitting on a stockpile of energy, but they simply are not producing the right hormones to burn that energy. They need glucose, which means they need to eat because the body only stores a very limited amount of glucose in the liver. The primary reason this feeling comes up for people is that their bodies have become insulin resistant, which means they literally cannot burn fat.
Understanding the Effects of Insulin Resistance.
Cells become insulin resistant in the same way that cells become leptin resistant. Because a person dealing with insulin resistance has less insulin receptors per cell, their cells are not hearing insulin's signals as effectively. The pancreas responds to this by releasing even more insulin. It’s thinking, “Cells aren’t listening to me so I’m going to yell my message louder!” The pancreas needs cells to hear this message otherwise blood sugar will get too high, which the body does everything in its power to prevent.
For this reason someone who is insulin resistant needs to produce a lot of insulin just to perform the basic job of making sure blood sugar doesn’t get too high. Even when fasting, a person who is insulin resistant has elevated levels of insulin in their blood. This is why the easiest way to measure insulin resistance is by having a doctor do a fasting insulin test.
This is a routine test and is a very good metric for identifying insulin resistance. From what I’ve read any number over five indicates insulin resistance. Ask your doctor to interpret the results, but I would advise caution if the given number is considered “normal”, because these “normal” ranges are based on populations of people who are widely insulin resistant. (Pretty much anyone who is overweight is also insulin resistant.)
Insulin resistance in general is at the heart of a laundry list of modern chronic diseases. When a person becomes insulin resistant–meaning they can’t burn fat effectively–they become perpetually hungry (mostly for sugars and carbs), leading to more weight gain, more leptin resistance and the vicious cycle continues. All of this extra insulin and leptin in the system also contributes to chronic inflammation and any doctor will verify that wherever there is disease, there is also inflammation.
It’s no wonder that The United States is the most obese country in the world. The typical American diet is full of foods that spike insulin. The obvious culprit is all the sugary drinks and snacks, but actually the perpetrator doing the deed for most people is probably highly processed carbohydrates. Things like rice, pasta, bread, oatmeal, chips and crackers all spike insulin levels just as much as sugar, if not more.
Processed carbs usually have higher numbers for a metric called the glycemic index (GI). This is basically a measurement of how fast a certain food is turned into glucose and released into the bloodstream. Pure glucose has a number of 100 and something like celery would have a GI of 0. In general eating foods with a lower GI are better because when we spike blood sugar, we spike insulin.
Why we Should eat Butter.
I haven’t forgotten about my possibly perplexing advice to eat butter, alluded to in the title, so let me address that now. Full fat, raw butter (meaning not pasteurized) and coming from a cow who ate grass for it’s entire life, is full of healthy fats. The healthy fats in real butter do not raise insulin at all and in my experience–and for most people–lead to a feeling of being full and satisfied. Margarine is not a good choice because it’s full of trans fats and these are the fats that make us fat and unhealthy.
Over time when we switch to a diet coming primarily from healthy fats as opposed to sugars and carbohydrates, we are actually training our bodies how to burn fat. The human body is incredibly adept at adapting to it’s surroundings so if we give it glucose, it learns to burn glucose. If we give it fat, we’re training it to burn fat. It really is that simple.
Please let me be clear that I am not advocating against exercise. Exercising has notable benefits including increasing memory and learning capabilities and lowering risk factors for most diseases, just to mention a few. Exercise is a vital component of a healthy lifestyle. The main takeaway from this article is that maintaining a healthy weight is all about metabolism and hormones, not exercising. So if a person who wanted to shed a few pounds of belly fat had a choice between an hour at the gym, or an hour at the grocery store, I would suggest they spend that hour at the store filling their cart with high quality fatty foods.
At the bottom of this related post there is a list of such foods–all full of healthy fats–that would be great additions to a healthy diet. It also goes into greater detail about some of the information in this post as well as cites a number of sources for further reading.