04 Oct 2018 Is Depression Really Caused By A Chemical Imbalance?
I know this is a touchy subject.
Not only is mental health a very personal issue, but there’s a stigma surrounding mental health disorders that often comes in the form of blaming those who have these issues or even discounting the legitimacy of these disorders.
And, those who aren’t in favor of the chemical imbalance theory often get lumped in with the people who stigmatize these disorders. Because of these associations, I want to first clarify that I’m NOT blaming anyone for their state of mental health nor am I discounting that these conditions are legitimate and biological in nature.
With that out of the way, we can talk about what’s really causing mental health disorders like depression.
The mainstream belief is that these conditions are caused by specific chemical imbalances in the brain and that these imbalances can only be fixed with prescription medications. This is also known as the “chemical imbalance theory.”
This theory has, in part, led to a dramatic rise in the prescription of antidepressant medications over the past few decades, to the point that over 10% of Americans are taking antidepressants. It has also fueled the massive growth of the multi-billion-dollar antidepressant drug industry.
But, this mainstream theory doesn’t hold up and these medications are not the solution to the growing problem of depression and other mental health disorders.
The Many Flaws of The Chemical Imbalance Theory
First, I’d like to make it clear that I’m not suggesting that the chemicals in our brains don’t affect our mental health. In fact, I would go as far as to say the exact opposite: our mental health and physical health are inextricably linked to the point that there really is no separation – our mental health isn’t at all distinct from our physiology.
And this leads us to one of the biggest flaws of the chemical imbalance theory, which is that the hormones and neurotransmitters that affect our mental health aren’t affected by what’s going on in the rest of our body.
The idea that our mind is separate from our body is extremely common. It’s assumed that our thoughts, mood, and outlook on life are completely independent of the foods we eat, chemicals we’re exposed to, sunlight we get, and all other factors of our environment. But this isn’t at all the case.
There’s no true separation between our mind and body. All these environmental factors affect us on a physiological level, and this includes affecting the many aspects of brain physiology that are related to our thoughts, mood, and perspective through which we see the world. This includes effects on our “brain chemicals,” like serotonin, dopamine, GABA, and norepinephrine.
So the issue isn’t determining whether chemicals in our brain affect our thoughts or mood, the issue is the thinking that these chemicals can’t be changed by our environment and instead are, presumably, primarily genetically determined. This then suggests that there’s nothing we can do about these “chemical imbalances” other than fixing them with prescription medications.
Along with this misconception is the fallacy that mental health disorders as complex as depression can be broken down to simple chemical imbalances (too little or too much of a single neurotransmitter, for example), which is what the antidepressant medications are aimed at treating.
Perhaps surprisingly, these flaws have been extensively acknowledged in the scientific literature:
“While neuroscience is a rapidly advancing field, to propose that researchers can objectively identify a “chemical imbalance” at the molecular level is not compatible with the extant science. In fact, there is no scientifically established ideal “chemical balance” of serotonin, let alone an identifiable pathological imbalance. To equate the impressive recent achievements of neuroscience with support for the serotonin hypothesis is a mistake.” (1)
“In short, there exists no rigorous corroboration of the serotonin theory, and a significant body of contradictory evidence. Far from being a radical line of thought, doubts about the serotonin hypothesis are well acknowledged by many researchers, including frank statements from prominent psychiatrists, some of whom are even enthusiastic proponents of SSRI medications.” (1)
Nonetheless, the chemical imbalance theory is still the popular narrative outside of the scientific literature. While this theory is heavily flawed, it wouldn’t be nearly as dangerous if the prescribed medications were actually safe and effective.
Antidepressants are some of the most prescribed drugs in the United States, the most common of which are SSRIs. These medications are based on the idea that depression is caused by a lack of serotonin, a notion that has become so pervasive that serotonin is colloquially considered the “happy hormone.” Simply put, this is absolutely not the case, but I’ll dig into that in more detail another time. For now, the complete failure of these drugs will have to do as evidence against this supposition.
Antidepressant drugs are incredibly ineffective, to the point that they’re barely more effective than placebos, if at all, and should never have been approved by the FDA (2, 3, 4, 5, 6, 7). This is almost unequivocal in the research, which is quite surprising considering the persistent mainstream narrative about the effectiveness of these drugs and how universally they’re prescribed.
Their lack of effectiveness is nicely summed up in this quote:
“Antidepressants are supposed to work by fixing a chemical imbalance, specifically, a lack of serotonin in the brain. Indeed, their supposed effectiveness is the primary evidence for the chemical imbalance theory. But analyses of the published data and the unpublished data that were hidden by drug companies reveals that most (if not all) of the benefits are due to the placebo effect. Some antidepressants increase serotonin levels, some decrease it, and some have no effect at all on serotonin. Nevertheless, they all show the same therapeutic benefit. Even the small statistical difference between antidepressants and placebos may be an enhanced placebo effect, due to the fact that most patients and doctors in clinical trials successfully break blind. The serotonin theory is as close as any theory in the history of science to having been proved wrong. Instead of curing depression, popular antidepressants may induce a biological vulnerability making people more likely to become depressed in the future.” (3) (emphasis mine)
And these drugs are not without side effects. They’ve been shown to cause sexual dysfunction, weight gain, complications during pregnancy, insomnia, apathy and emotional blunting, increases in suicidal ideation and attempts, increases in violent and aggressive behavior, and many other “side effects” (3, 6, 8, 9, 10, 11, 12, 13). They also increase the risk of becoming depressed again and can cause severe withdrawal symptoms when stopped (3, 8, 14, 15).
Due to their lack of effectiveness and side effects, studies have shown that very few people treated with antidepressant medications stick to the treatment (15) and the outcomes of people using antidepressants are worse than those who aren’t treated with antidepressants (5, 16).
Considering their lack of effectiveness, dangerous side effects, and the presence of other treatments that work just as well (if not better), you could even say that it’s irresponsible to continue to sell and prescribe these “antidepressant” medications, as is suggested in this quote:
“When different treatments are equally effective,
choiceshould be based on risk and harm, and of all of [the available] treatments, antidepressant drugs are the riskiest and most harmful. If they are to be used at all, it should be as a last resort, when depression is extremely severe and all other treatment alternatives have been tried and failed.” (3)
I don’t think it’s much of a stretch to claim that, as several researchers have suggested, the prescription of these drugs is the result of a triumph of marketing over science, which is evidenced even by the name “antidepressant”:
“One day we may look back and marvel at the stroke of marketing genius that led to calling these medications antidepressants in the first place. Kirsch et al. (2002) have demonstrated that just because a pill is called an antidepressant, it doesn’t necessarily make it so.” (17)
“Not only does this evidence show that [antidepressant] drugs are little different from placebo, but also that there are no grounds to believe they have specific effects that would justify their classification as ‘antidepressants’” (6)
“Regarding SSRIs, there is a growing body of medical literature casting doubt on the serotonin hypothesis, and this body is not reflected in the consumer advertisements. In particular, many SSRI advertisements continue to claim that the mechanism of action of SSRIs is that of correcting a chemical imbalance… Yet, as previously mentioned, there is no such thing as a scientifically established correct “balance” of serotonin. The take-home message for consumers viewing SSRI advertisements is probably that SSRIs work by normalizing neurotransmitters that have gone awry. This was a hopeful notion 30 years ago, but is not an accurate reflection of present-day scientific evidence.” “The incongruence between the scientific literature and the claims made in FDA-regulated SSRI advertisements is remarkable, and possibly unparalleled.” (1) (emphasis mine)
It’s quite clear that the chemical imbalance theory has been discredited, yet the damaging effects of this theory stretch beyond the abysmal failure of antidepressant medications.
“Side Effects” of the Chemical Imbalance Theory
There’s another problem with this theory beyond it being completely inaccurate and leading to the prescription of treatments that don’t work.
The idea that our thoughts, mood, and general happiness are determined by chemical imbalances that we have absolutely no control over fosters helplessness. It takes away our power to improve our mental health and encourages us to rely on ineffective medications.
These effects have been shown in studies where patients have been told that their mental health disorders are due to chemical imbalances:
“The group who was told they had abnormal serotonin levels found medication more credible than psychotherapy and expected it to be more effective. They also had more pessimism about their prognosis and a lower perceived ability to regulate negative mood states, yet experienced no reduction in self-blame.” (18) (emphasis mine)
This sort of helplessness only makes conditions like depression worse by encouraging the feeling that nothing can be done to improve our thoughts, mood, and perception. But that couldn’t be farther from the truth!
What Can We Do About Depression?
Before I begin explaining what can be done to improve or alleviate depression and other mental health disorders, I want to emphasize that I’m not suggesting that these conditions don’t have a physiological basis, that we should blame ourselves for having them, or that they’re simply “behaviorally-based.”
What I am suggesting is that we aren’t powerless or helpless in these situations. As I mentioned earlier, it’s completely illogical to create a separation between our environment and our mental health as if they aren’t directly interdependent. So, there are things that we can do that directly affect the biological underpinnings that affect our thoughts, mood, and perception.
Let’s first consider that depression and other mental health disorders are, in essence, a result of chronic stress. And by chronic stress, I’m not referring to psychological stress, but rather physiological stress.
Physiological stress is a product of a lack of energy, where our energy demands are greater than our energy supply. And, it’s been shown that this stress, or lack of energy, directly affects our feelings of well-being and causes a physiological response that we consider “depression,” as well as other mental health disorders (19, 20, 21, 22, 23, 24, 25, 26, 27, 28).
But, addressing this energy deficiency can be rather tricky, as it’s affected by all aspects of our environment.
This includes psychological stress, social interaction and relationships, leisure, and loneliness, all of which directly affect our health and well-being (29, 30, 31, 32, 33, 34). This may not be all that surprising, as these are the environmental factors most commonly considered when it comes to mental health disorders.
However, when mental health disorders are reduced to simple chemical imbalances these factors may be ignored. Considering that these aspects of our environment have direct effects on the physiological factors that affect our mental health, ignoring these factors would be a costly mistake.
Other factors like exercise and nutrition also play a major role. It’s widely recognized that these facets of our environment affect our health, but their powerful effects on our thoughts, mood, and sense of well-being are often ignored.
Considering that the psychological aspects of our health are directly influenced by energy balance, it’s imperative that we address the factors affecting our production and usage of energy if we want to improve depression and other mental health disorders. To learn more about how you can address these factors, sign up below for a free 6-day email mini-course on depression, health, and energy balance.
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