Mental health disorders are prominent in today’s society, with the two most common conditions, anxiety and depression, being the leading cause of disability. In an attempt to find new therapeutic approaches to treating mental health conditions, there has been a growing interest in the role of diet and nutrition on mental health. Numerous studies have suggested both the therapeutic and detrimental role of certain diet patterns on mental health disorders. The two most prominent case studies are the therapeutic effects of the Mediterranean diet and the detrimental effects of the Western diet on mental health pathology (Firth, 2020).
The Mediterranean diet consists of high consumption of fruits, vegetables and fatty fish and low consumption of red meat. This diet pattern has been associated with reduced incidence of depression. On the other hand, the Western diet, which consists of high consumption of saturated fats and low consumption of fish, has been shown to have detrimental effects on mental health. In a corroborating study, children who ate more vegetables, fish and fruits, were less likely to have ADHD, whereas consuming fast food and soft drinks was associated with high incidence of ADHD (Clay, 2017). This phenomenon calls to question which nutritional factors in these diets contribute to their effect on mental health (Lachance, 2015).
One potential factor is the effect of carbohydrates on the brain chemistry. Highly glycemic foods (high in carbohydrates) have been associated with depression and have even been shown to induce depressive symptoms in healthy volunteers (Firth, 2020). A possible mechanism for this observed effect is the rapid fluctuations in blood glucose levels. A highly glycemic diet induces a compensatory response, in which blood glucose is lowered to accommodate the high glucose diet. This decrease in blood glucose then triggers the release of several hormones such as cortisol, adrenaline, growth hormone and glucagon, which have been implicated in leading to anxiety and irritability (Firth, 2020). The hormonal fluctuations due to rapid changes in glucose levels may help explain the detrimental effects of Western diet on mental health. However, it is important to note that a highly glycemic diet is also associated with obesity and diabetes, which may affect mental health. Although causality cannot be assumed, the effect of the consumption of carbohydrates on the brain offers a promising mechanism for how food affects mental health.
Another potential factor is the immunostimulatory effect of high calorie meals rich in saturated fats seen in Western diets. Foods high in saturated fats have been shown to stimulate the immune response and induce an inflammatory effect on the body (Lachance, 2015). Such inflammatory effects have been associated with depression. On the other hand, in controlled trials, anti-inflammatory drugs have been shown to decrease depressive symptoms (Firth, 2020). Mediterranean diets typically have anti-inflammatory effects, which may explain the reduced incidence of depression in individuals with the Mediterranean diet.
Additionally, our diet patterns can alter our gut microbiome, or the trillions of bacteria, viruses and archaea that live in our gut, which may have an effect on mental health. The gut microbiome has the ability to interact with and regulate the brain in various ways through neurotransmitters and hormones. Probiotics and certain diet patterns can potentially disturb the equilibrium in the gut microbiome and consequently affect the gut’s regulation of emotion and mood in the brain. For instance, a study found major depressive symptoms were associated with altered gut microbiome (Firth, 2020). Additionally, when fecal gut microbiota from humans with depression were transferred to healthy rodents, it seemed to induce depressive symptoms in the rodents (Firth, 2020). These findings suggest the role of gut microbiome in the regulation of brain pathways and consequently mental health.
Lastly, there are certain nutritional deficiencies in the Western diet that may help explain the difference between Western and Mediterranean diets. Deficiencies in vitamin B12, B9 and zinc have been shown to cause depressive and dementia-like symptoms (Lachance, 2015). These nutrients are believed to be building blocks of numerous essential monoamine neurotransmitters, like serotonin, norepinephrine and dopamine. The reduced synthesis of these neurotransmitters in individuals with Western diets may be a possible reason for the high incidence of mental illness.
Mental health is an ever-growing concern in our society. Despite recent developments in intervention methods, only about one in three patients receive effective treatment (Lassale, 2018). Therefore, it is crucial to look for new, more effective ways to treat individuals with mental health conditions. Although diet by no means can be a replacement for professional help, the recent findings on the relationship between food and mental health point promise the potential for nutrient supplements and dietary changes as a viable intervention method. A healthy diet not only can have therapeutic effects on the brain, but also improves an individual’s general lifestyle and every day functioning. At this point, it is hard to assume that foods have a direct causal effect on mental health. However, further research must be done to establish this intricate relationship.
Traumatic brain injury (TBI) is defined as temporary or permanent altered neurological states or deficits due to external forces and includes concussions, contusions and hemorrhages. In the United States, over 1.7 million people suffer from TBI and severe TBIs are the leading causes of injury-induced death and disability (Georges, 2023). Globally, an estimated 50% of the population will experience a TBI, amounting to a cost of around 400 billion USD every year (Chan, 2022). TBI-related emergency department visits and hospitalizations have also risen in the past decade, mostly due to the medicalization of brain injuries and the growing awareness of the severity of TBIs.
There are two types of injuries that can cause TBIs. Primary injuries involve direct impact on the brain, like when an athlete bumps his head against a hard surface. Secondary injuries usually occur some time after a primary injury and the brain damage is exacerbated due to some molecular or inflammatory cascade. For instance, after a brain injury, excitatory neurotransmitters are released. These neurotransmitters cause an increase in the level of intracellular calcium, leading to the activation of molecules that degrade neurons. This degradation of neurons can even lead to a breach in the blood-brain barrier (Galgano, 2017). The symptoms of TBIs include nausea, dizziness, blurred vision/hearing, memory/cognitive deficit, and emotional distress like irritability, depression or anxiety.
The most common causes of TBIs are falls and car accidents. Other causes can include sports injuries, military injuries (explosives), and physical assault. The highest occurrence of TBIs tends to occur in the 0-4 age group and the 65+ age group (Galgano, 2017). Babies are at higher risk of falling at home, and some brain injuries occur before or during delivery of the baby. Shaken baby syndrome is another potential cause of TBIs in infants. The older population are at particular risk for TBIs and TBI-related consequences, as severe injuries due to falls are much more likely and the older generation are less likely to seek professional health care after a brain injury (Kureshi, 2023). This is due to age-related physical or cognitive problems that hinder healthcare access. The adolescent age group (15-24) is also at a high risk for TBIs as they are usually the most active and more likely to be involved in sports injuries. The sports with the highest incidence of TBIs include cycling, football, baseball and basketball.
TBIs have a very broad spectrum of symptoms. Mild TBIs, known as concussion, usually do not have severe symptoms and don’t require extensive treatment. Usually there is an altered mental state after the injury, ranging from confusion to unconsciousness, but the symptoms are usually transient. Repeated concussions, however, can lead to chronic traumatic encephalopathy (CTE), which have more severe psychological and cognitive consequences. Disorganized speech, tremors, difficulty with attention and memory, and mental health disorders are some of the symptoms of CTE. Currently, there is no conclusive way of diagnosing CTE, except for a brain autopsy, which has to be done after death. CTE has also been associated with aggressive and suicidal behavior, often seen in retired boxers and NFL players (Antonius, 2014). These psychiatric disorders are responsible for a lot of the suicidal behavior seen in retired athletes, particularly boxers (Galgano, 2017).
There are other more severe TBIs that cause direct damage to brain structures and components. For instance, extra-axial hematoma results from bleeding of an artery or a vein in the brain, often caused by skull fractures. Diffuse axonal injuries (DAIs) are characterized by shearing of neuronal axons due to rapid rotational acceleration/deceleration of the head and can cause altered consciousness or even an inability to regain consciousness (Georges, 2023).
TBIs and mental health disorders have been highly linked to one another. In the first year after an injury, 77% have received a diagnosis for psychiatric disorders, like depression, anxiety, PTSD, schizophrenia and alcohol use disorder. Individuals with a history of TBIs were twice as likely to experience anxiety or depression (Kureshi, 2023). This was especially true in war veterans that experienced TBIs from combat. Military personnel that experienced TBIs were more likely to experience PTSD and have higher suicide rates (Chan, 2022).
The relationship between TBIs and mental health disorders are complex. Oftentimes, they have overlapping symptoms. Fatigue, dizziness, memory/attention deficit, and emotional instability are common symptoms of TBIs, but are also characteristic symptoms of anxiety and depression. TBIs and mental health disorders often exacerbate each other, with the causal relationship going both ways. TBIs can cause mental health disorders, and vice versa. For instance, emotional trauma from a TBI can lead to PTSD. On the other hand, behavioral problems and cognitive deficits from mental health disorders may make an individual more likely to be involved in an accident and experience a TBI.
Another complication is that both TBIs and mental health disorders have very broad spectrums in terms of their symptoms and causes. And in both cases, diagnosing a TBI or mental health disorders is often difficult as there is no universally agreed upon method of diagnosis. Unfortunately, in the current healthcare system, TBIs and mental health disorders are mostly disconnected. It is crucial to recognize that TBIs and mental health are deeply interconnected and healthcare professionals must be able to clearly communicate with one another to understand their complex relationship and effectively be able to treat both.
Mental health conditions are misdiagnosed more often than one might think. Anxiety and depression often go undiagnosed, or are misdiagnosed in place of medical diagnoses, like medical conditions that cause chest pain, lethargy or shortness of breath. More severe mental health disorders like schizophrenia and bipolar disorders are often misdiagnosed and confused with each other. In a study done on Canadian primary care clinics, it was found that 65% of major depressive disorder, 85% of panic disorder, 71% of generalized anxiety disorder, and 97% of social anxiety disorder were misdiagnosed (Vermani, 2011). In another study on clinics in Ethiopia, the misdiagnosis rate of severe psychiatric disorders was almost 40%, with the most commonly misdiagnosed disorder being schizoaffective disorder (Ayano, 2020). These numbers are alarming, as misdiagnosis of a mental health disorder can lead to inappropriate treatment or medication options, leading to worsening of the condition. Therefore, it is crucial that the correct diagnosis be made so that the proper course of treatment can be recommended by the doctor.
Why do misdiagnoses happen? One major reason for the misdiagnosis of mental health disorders is that many disorders have overlapping symptoms, which makes it challenging to make the appropriate diagnosis. Unlike many medical disorders, mental health disorders do not have signs or symptoms that are specific to that particular disorder. For instance, the most common symptom of schizophrenia, hallucination/delusion, can also occur in patients with bipolar disorder or major depressive disorder. Also, a patient may simultaneously have multiple mental health conditions, making the proper diagnosis even more difficult. For example, 60% of schizophrenic patients had comorbid depression (Ayano, 2020). Bipolar disorder and depression were the two disorders that were most confused with each other due to depression being one of the defining symptoms of bipolar disorder.
Similarly, in many cases, physical or developmental symptoms are misinterpreted as a mental health condition. ADHD is a commonly misdiagnosed disorder in children. Symptoms of ADHD include sleep irregularities, fidgeting, difficulty focusing and inability to sit still. However, a child with sensory processing disorder (SPD), which makes you overly sensitive to your senses, can have similar symptoms to ADHD (Akers, 2019). In many cases, children with autism are misdiagnosed with ADHD or other mental health disorders (Au-Yeung, 2018). Difficulty focusing and inability to sit still may simply be due to delayed development of self-discipline, rather than a symptom of ADHD (Akers, 2019). Similarly, a medical condition, like hypothyroidism, which causes lack of energy and lethargy, can be misinterpreted as an underlying symptom of depression.
Another barrier contributing to the misdiagnosis of mental health conditions is that patients may not report their symptoms in an appropriate manner. In a medical diagnosis, numerous tests can be done to find the exact underlying cause of physical symptoms. However, in a mental health diagnosis, clinicians rely solely on the patient’s self-reporting of their symptoms. Patients may feel less inclined to disclose matters about more sensitive topics, like drug abuse or trauma. Patients may also not understand the importance of disclosing certain symptoms. For example, a patient with bipolar disorder may not consider the manic period as problematic, especially when compared to the depressive period. The patient may see the manic period as the “stable” phase, as they are able to be productive without any of the depressive symptoms, and therefore when discussing with a clinician, not report the manic phase as a symptom (Akers, 2019).
Misdiagnosis of mental health conditions can have grave consequences. One such effect is the inappropriate recommendation by the clinician for the course of treatment. Inappropriate medication can have a worsening effect on the symptoms and make proper treatment that much more difficult. For example, Adderall, a common medication for ADHD patients, can cause impairments in working memory and cognitive decline in individuals that don’t have ADHD. Also, when the recommended treatment is not working, the patient may feel shame or guilt, thinking that it is their own fault, potentially leading to symptoms of anxiety or depression. Or, the patient may fault the clinician and develop a distrust of healthcare professionals, preventing future visits to the clinic (Akers, 2019).
It is clear that the appropriate diagnosis of mental health disorders is crucial to treatment, but how do we reduce misdiagnoses? Most importantly, a patient must give honest, clear reports of their symptoms. It is crucial that patients don’t feel shame in disclosing their symptoms or life history, while healthcare professionals have the responsibility to provide a safe space where the patient feels comfortable disclosing information about themselves. Patients must also be well-informed about different mental health conditions, so that they understand the importance of reporting certain symptoms. It is also important for clinicians to carefully evaluate each patient on a case-by-case basis to make the appropriate diagnosis based on the patient’s symptoms, background, and patient history. Creating an accurate criteria for diagnosing different mental illnesses is no easy task; however, understanding why misdiagnoses happen and how we can prevent them is a step in the right direction.