Chapter 5

Mental Disorders Are Metabolic Disorders

The following 1938 observation from physicists Albert Einstein and Leopold Infeld is critically important:

Creating a new theory is not like destroying an old barn and erecting a skyscraper in its place. It is rather like climbing a mountain, gaining new and wider views, discovering unexpected connections between our starting point and its rich environment. But the point from which we started out still exists and can be seen, although it appears smaller and forms a tiny part of our broad view gained by the mastery of the obstacles on our adventurous way up.¹

For any new theory to be taken seriously, it must incorporate what we already know to be true. It can’t just replace it; it must tie together our existing knowledge and experience into a broader understanding—one that will widen our perspective and offer new insights.

Mental health professionals have various camps at the base of Einstein and Infeld’s mountain. Some believe mental illnesses are biologically based, that they arise from a chemical imbalance. They prescribe medications and have seen them work. Other professionals are focused on psychological and social issues. They have helped people through psychotherapy and social interventions and have seen these treatments work. They know with certainty that at least some mental disorders involve psychological and social issues; correcting these issues without any pills can solve the problem, at least for some patients. In reality, all these perspectives are correct. That this is so—and how it is so—can be seen clearly from the vantage point of our new theory: the theory of brain energy. This theory is based on one overarching concept—mental disorders are metabolic disorders of the brain.

In the medical world, new theories allow us to better understand the connections between treatments and disorders that we currently can’t explain. They help us better predict future research findings. And they help us develop more effective treatments for the future. The theory of brain energy will do all of this for mental disorders. But its impact is bigger than just mental health. This theory ties together medical disciplines that most people think are unrelated—psychiatry, neurology, cardiology, and endocrinology. Others, too. All these disciplines have their own camps at the base of the mountain as well. Sometimes they work with each other and the practitioners see the connections between disciplines, but far too often, they don’t. A patient might visit a cardiologist who prescribes their heart medicine, an endocrinologist who manages their diabetes prescriptions, and a psychiatrist who prescribes medication for bipolar disorder, with these specialists never communicating with each other. I’m hopeful that the brain energy theory will change this, leading to better cross-specialty collaboration and more effective and comprehensive care. Given what we’ve already seen about the connections between these disorders, this kind of communication and collaboration seems only logical. It may soon be possible to treat or prevent all of these conditions with one integrated treatment plan.

In order to prove, or at least strongly support, the theory of brain energy, the upcoming chapters will show that:

As we explore these lines of evidence, not only will it become clear that mental disorders are indeed metabolic disorders of the brain, it will become clear why this is important and what it means for treatment.

The Metabolic Ripple Effect

To suggest that so many different disorders stem from metabolic problems may sound far-fetched. Interestingly enough, while the medical field now groups obesity, diabetes, and cardiovascular disease together as metabolic disorders, that was not always the case. After all, they have very different symptoms, and they require different medications and different treatments. There are still different specialties that focus on these different disorders—obesity medicine (obesity), endocrinology (diabetes), cardiology (heart attacks), and neurology (strokes). However, they all affect the entire body, and people who have one such disorder are at higher risk of having another one. Not everyone who is obese has a heart attack or diabetes. Not all diabetics are obese. Not all people who have a stroke have diabetes. But while different people have different signs and symptoms, they are all interconnected.

The effects of metabolic disorders on the body aren’t limited to an increased risk of the other metabolic disorders like obesity, diabetes, heart attacks, and strokes. As we’ve already discussed, these people have increased rates of Alzheimer’s disease, epilepsy, and mental problems, too. But people with metabolic disorders are also more likely to develop innumerable other illnesses not usually viewed as metabolic. These include liver problems, kidney problems, nerve problems, brain problems, hormonal problems, joint problems, gastrointestinal problems, autoimmune problems, and even cancer.

Most people think that metabolic disorders are simple problems with simple solutions. They think they know the “root causes” of these disorders—behaviors like eating too much, not exercising enough, and/or smoking cigarettes. As long as people don’t overeat, or under-exercise, or smoke, they will be perfectly fine, metabolically speaking. See? Simple.

But when it comes to metabolism, nothing is simple.

Let’s look at an example. Mark was a seemingly healthy, thin, and fit forty-five-year-old man who developed multiple sclerosis (MS), an autoimmune disorder. To treat his MS, he was prescribed a medication called prednisone, a corticosteroid. Within weeks, he was bloated and gaining weight. Within a month, he developed pre-diabetes and was prescribed a diabetes medication. Unfortunately, weight gain and high blood sugar are both known side effects of prednisone.

Over the next six months, Mark gained forty pounds. Not all of this weight came out of nowhere; his behavior—specifically, his diet and exercise routine—changed dramatically. Up until his diagnosis, he had always eaten well and exercised vigorously several times a week. But corticosteroids like prednisone are known to increase appetite, and Mark had started craving and eating a lot of junk food, something he’d never done before. He tried to keep up with his exercise routine, but as he gained weight, it became harder and harder. He still managed to exercise some, but it was nothing like before. Mark’s risk markers for cardiovascular disease worsened, including an increase in his blood pressure and lipids. He was now well on his way to a heart attack or stroke. Oh . . . and he also developed anxiety and mild depression. But who wouldn’t be depressed and anxious in his situation? His doctor told him to try yoga and go on a diet. Unfortunately, that advice wasn’t all that helpful.

What is the root cause of Mark’s metabolic disorders? Within six months of starting the corticosteroid, he developed diabetes and obesity. The evidence is overwhelmingly clear that the culprit was the medication, not Mark’s willpower or discipline. His cravings and lack of energy are symptoms of metabolic dysfunction. His depression and anxiety are also known side effects of this medication. In some ways, he’s lucky that he didn’t get manic or psychotic, which are also possible side effects.

Reactions like Mark’s happen all the time with medications like prednisone. Other medications can cause these kinds of metabolic problems, too, including many psychiatric medications. But the takeaway here isn’t that one should never take these medications: autoimmune disorders like Mark’s can cause permanent organ damage, and the side effects of treatment are often determined to be a price worth paying when weighed against the severity of a disease. The point is that metabolic problems are not simple, nor are they avoidable through sheer willpower. Medication is only one of many, many possible causes. For example, a person who has experienced horrible childhood abuse is likely to have altered levels of cortisol, the body’s equivalent hormone to prednisone. Perhaps unsurprisingly, people with a trauma history are more likely to develop metabolic disorders . . . and mental disorders, too. And once people develop a metabolic problem, symptoms and lifestyle changes like Mark’s aren’t unusual at all.

What Is Metabolism?

When most people hear the word “metabolism,” they picture our bodies burning fat and calories. The common wisdom is that people with a “high metabolism” are skinny and have trouble gaining weight, while people with a “low metabolism” are overweight and gain weight easily—even if they don’t eat that much. That’s where metabolism begins and ends for most people.

Metabolism is about so much more than burning calories, though that’s part of it. It influences every aspect of the way our bodies function.

To make energy, our bodies need food, water, vitamins and minerals, and oxygen—we breathe in oxygen and breathe out carbon dioxide, a waste product of metabolism. When we eat food, it gets broken down into carbohydrates, fats, and amino acids, along with the vitamins and minerals that are hopefully also there. All of this is absorbed into our bloodstream and shuttled around the body. Once nutrients arrive at cells and enter them, they are used as building blocks for things like proteins or membranes. Some might be stored as fat for a rainy day. But most of these nutrients will be converted into adenosine triphosphate (ATP), which is the primary energy molecule of the cell. ATP makes the machinery of the cell work.

That’s the basic, high school biology version of metabolism. A one-sentence definition might be the following: Metabolism is the process of turning food into energy or building blocks for growing and maintaining cells, as well as the appropriate and efficient management of waste products. Metabolism is how our cells work. Our metabolism determines our cellular health, how our bodies and brains develop and function, and how we allocate resources to different cells at different times to optimize our survival. Metabolism allows some cells to grow and thrive and lets others shrivel up and die in a complex cost-benefit analysis that prioritizes healthy and advantageous cells over those that might be old, weak, or simply more expendable. As the body’s resource management system, metabolism is all about adaptation. Our environment is constantly changing, and so are our circumstances in the environment. As a result, our metabolism is constantly changing to keep up with the shifts around us. These adaptations in metabolism allow us to thrive in optimal environments or to simply survive in situations that are stressful to the body, like food scarcity. But the availability of food isn’t the only change metabolism responds to—numerous other factors play a role, like psychological stress, light exposure, temperature, how much sleep we get, hormone levels, and the amount of oxygen available to cells. At the end of the day, metabolism is the body’s battle to stay alive. Many biological authorities would say that metabolism defines life itself.

Energy Imbalances

Metabolism is how our body creates and uses energy. And we can think of problems with metabolism as energy imbalances.

Problems with metabolism lead to problems in the way cells function. This goes for all cells in the human body. For instance, when heart cells are metabolically compromised, they don’t work as well to pump blood. Brain cells need precise control. They need to be turned on at appropriate times and then turned off at appropriate times. When brain cells are metabolically compromised, these on/off processes can be disrupted. Precision is everything when it comes to brain function, and as we will see, this disruption can result in what we know as symptoms of mental illness.

The brain is the most complicated organ in the human body. In fact, the adult human brain is estimated to have about one hundred billion neurons. On top of that, there are an additional ten to fifty glial cells per neuron. The neurons are “nerve cells,” and the glial cells are often thought of as support cells to the neurons. Combined, there are about one trillion to five trillion cells in the human brain. One group of researchers challenged this estimate, suggesting it’s closer to eighty-six billion neurons and eighty-four billion glial cells, or 170 billion cells total.² Regardless, it’s a lot of cells!

What coordinates the function of all these cells? Many people would say neurotransmitters, the cell’s messenger chemicals. We can think of neurotransmitters as either “go” signals or “stop” signals, often categorized as excitatory (go) or inhibitory (stop). There are other variations, but these distinctions will suffice for now. They have been the primary focus of neuroscientists and biological psychiatrists for decades. But what controls neurotransmitters? How do cells know when to release them? Many would say their release is triggered by neurotransmitters from other cells. I’m sure you see the problems with this answer. It is partially correct. However, as I will discuss throughout the remainder of this book, there are numerous other factors that dictate the action of brain cells.

We’ve established that cells need energy to work. This energy is used for all sorts of different things throughout the body, including making muscles function, creating and regulating hormones, and making and releasing neurotransmitters. The parts of the body that need the most energy tend to be the parts of the body most affected by metabolic problems. As you might imagine, topping the list are the brain and the heart.

Although the brain makes up about 2 percent of the body mass, it uses about 20 percent of the body’s total energy at rest. Brain cells are exquisitely sensitive to disruptions in energy supply, and when there’s a metabolic problem somewhere in the body, the brain usually knows. Given that our brains are the control centers of our bodies, they ultimately control our perceptions of reality. When there is a metabolic problem somewhere in the body, we might perceive pain, experience shortness of breath, or feel fatigued or lightheaded. If there is a metabolic problem in the brain itself, the signs and symptoms can take just about any form. Sometimes they are obvious, such as confusion, hallucinations, or a complete loss of consciousness. Other times, they are more subtle, like fatigue, trouble concentrating, or mild depression.

Sometimes metabolic problems are acute, meaning that they are abrupt and dramatic. These can take the form of a heart attack, a stroke, or even death. A heart attack, for example, is usually due to a blood clot in one of the arteries feeding the heart. Some of the heart cells stop getting enough blood and oxygen. This prevents them from producing enough energy. If blood flow isn’t restored quickly, the heart cells die. This is a metabolic crisis in the heart. A stroke is an acute metabolic crisis in the brain. The ultimate metabolic crisis is death itself, where the cells in the entire body stop producing energy. Many paths can lead to this whole-body energy failure—heart attacks, strokes, poisonings, severe accidents, cancer. They all result in the cells of the body no longer producing enough energy, and it is the lack of energy production that results in death.

Heart attacks, strokes, and death are all examples of absolute and acute energy problems that result in cell death. However, there are less dramatic situations in which the energy supply to cells is compromised: Instead of a complete shutdown of energy production, the cells simply aren’t getting enough energy. Instead of cell death, the cells don’t work quite right. Some of these metabolic problems can last for just a few minutes, while others might last for hours. Hypoglycemia, or low blood sugar, is a good example. It most commonly occurs when people haven’t eaten in a while. In mild cases, it results in feeling hungry, irritable, fatigued, or having trouble concentrating. In moderate cases, it might result in a headache or feeling depressed. In severe cases, it can result in hallucinations, seizures, or coma. If it progresses further, it can result in absolute metabolic failure—death. Before things get so severe, however, most people implement the obvious solution—they eat something. This raises blood sugar, and things begin to function normally again. Even if they don’t eat anything, the body has systems in place that usually prevent severe hypoglycemia. However, for diabetics who inject insulin or take medication to more forcibly lower blood sugar, these severe consequences are a real possibility. You might notice that brain symptoms dominate the above list of effects, even though the hypoglycemia is occurring throughout the entire body.

Other metabolic problems are not acute but instead chronic disorders with long-lasting symptoms—like diabetes, for example. Many people think of diabetes as high blood sugar. However, a paradoxical and interesting way to think about diabetes is as an energy shortage, or a deficit in energy production. Glucose is the primary fuel source for cells. In diabetes, cells have trouble converting glucose into energy. The levels of glucose in the blood can be high, sometimes very high, yet that glucose has trouble getting into cells where it can be used. Getting glucose from the bloodstream into cells requires insulin, a hormone produced by the pancreas. Diabetics have either a shortage of insulin or insulin resistance—a condition in which the body is not as responsive to insulin. When cells don’t have enough glucose, they aren’t able to produce enough energy. When they don’t have enough energy, they don’t work right.

Since glucose is the primary fuel source for most cells in the body, diabetes can affect many different parts of the body. But not everyone has the same problems. The symptoms of diabetes can be wide-ranging and can change over time. In the beginning, symptoms are usually mild. They can include things like urinating too much or losing weight unexpectedly. They can also include mental symptoms such as fatigue or trouble concentrating. As the illness progresses, different organs can be affected. Some people develop problems with their eyes, nerves, or brains. Some people have heart attacks or strokes. Others experience kidney failure or contract serious infections that are difficult to treat.

Why are the effects on people so different? Why don’t all diabetics end up with the same symptoms and the same body parts failing? The answer is complicated—and often related to metabolism.

Metabolism is affected by numerous factors. It is always changing. And it is different in different cells of the body at different times. Some cells can be functioning normally while others are dying. Some cells may gradually malfunction as the result of chronic energy deprivation. Metabolism is not all-or-nothing. It is controlled at a variety of levels. Some of the factors that affect metabolism do so broadly, while others are specific to distinct parts of the body. Some are specific to specific organs. Some are specific to specific cells.

Metabolism Is Like the Flow of Traffic

Think of it like this—the body is like a large city with lots of roads and highways. There is a lot of traffic. Each car is like a human cell. During rush hour, it can be hectic. If you’re in a car, it can feel chaotic. So many things to pay attention to: stoplights, cars changing lanes, someone on their cell phone swerving into your lane. If you look at the traffic from above, however—say, from the top of a skyscraper—it looks pretty orderly. The roads are organized. The cars and trucks are moving along. Some cars stop while other cars go. They wait their turn and then start going again. Cars go slow on certain roads but then speed up on highways. Some cars change lanes, and the cars around them have to slow down to let them in. Others might be having problems and be stuck on the side of the road. There might be some traffic accidents, causing other cars to take a detour. If you were to try to take in the specifics of each and every car at the same time, it would be overwhelming—there are too many cars, too many stoplights, too many other factors to keep in mind. But when you look at the big picture, traffic is moving along. The city is working. People are getting to where they need to go. The city is alive. It has energy; you can see it flow. This is the way to think about metabolism in the human body.

Back to the question I posed earlier—why do some people with diabetes have different symptoms? More important to the theory of brain energy, if all mental disorders are metabolic disorders, why doesn’t everyone with a mental disorder have the same symptoms?

Illnesses and symptoms are like traffic jams. Either traffic isn’t flowing optimally, or it stops altogether. One highway might represent the pancreas. An access road might represent a specific brain region that controls attention and focus.

What causes a traffic jam on a given road or highway? Myriad things. Car accidents, road construction, potholes, or traffic signals failing to work. The design and maintenance of the roads play a role, and the cars and drivers do, too. Some parts of the city have more frequent traffic problems. This can be due to poor design, poor maintenance, or more aggressive or careless drivers on those roads. The areas of the city with regular traffic problems represent “symptoms” or “illnesses”—places where the traffic isn’t “working” properly.

When it comes to human illnesses and symptoms, we are talking about parts of the body or brain that aren’t working properly. This is usually the result of an issue in one of three areas: the development, function, or maintenance of human cells. Cells must develop properly in order to meet the needs of the body. Function is making sure all the parts are doing what they are supposed to be doing, in the right ways at the right times. Maintenance is keeping everything in good shape. This is analogous to traffic needing adequate design and construction of roads and bridges (development); all the cars, drivers, and traffic lights working properly (function); and the whole system being regularly serviced—cars tuned up, roads patched, stoplights tested, etc. (maintenance).

In humans, these three things—development, function, and maintenance of cells—ultimately depend upon one thing: metabolism. If there are problems with metabolism, there will be problems in one or more of these areas. If the problems are significant enough, there will be “symptoms.”

So, what affects metabolism? Just like traffic in the city, many things! Diet, light, sleep, exercise, drugs and alcohol, genes, hormones, stress, neurotransmitters, and inflammation, to name a few. However, each of these things affects different cells in different ways. Depending upon the mix of factors that someone is exposed to, different cells and organs will be affected, resulting in different symptoms and different illnesses. Just like some roads are more susceptible to traffic jams, some cells are more susceptible to metabolic failure. Sometimes, parts of the body will function normally at times of low demand but begin to malfunction at times of increased demand—just like a rush-hour meltdown on a city highway that’s overwhelmed by commuters.

We’ve established that metabolism defines life itself; that it determines how cells function, that it affects and is affected by innumerable factors. In a way, of course mental disorders are related to metabolism. In essence, everything is! So what?

What I’ll show in the coming chapters is that metabolism is, in fact, the only way to connect the dots of mental illness. It is the lowest common denominator for all mental disorders, all of the risk factors for mental disorders, and even all of the treatments that are currently used. And, perhaps most significantly, although metabolism is complex, solving metabolic problems is usually possible, oftentimes through straightforward interventions.

Before I dive into the evidence for all of this, however, I first need to clarify what a mental disorder is in the first place. This question has long plagued the mental health field, and it centers on one issue in particular—the difference between normal mental states (especially stressful and adverse ones) and a mental disorder.