Students at Increased Risk of Developing Schizophrenia
Due to misrepresentation in the media, as well as scientists’ uncertainty about exactly what causes it, schizophrenia is arguably one of the most stigmatized and perplexing mental diseases known. Even so, schizophrenia affects 3.5 million adults in the US alone, and up to 50% of people go untreated. Its symptoms manifest in the form of hallucinations, movement disorders, and delusions, and those with schizophrenia often show no sign of it until after adolescence—namely in their 20’s or 30’s, which puts college-age people at a particularly high risk. College students are already at an increased probability of developing a mental illness, most likely because of elevated stress levels, alterations in sleeping patterns, and a higher likelihood of substance abuse. While schizophrenia used to be considered one of the mental conditions that was purely genetic, recent studies are beginning to suggest that certain activities and factors could very well prompt the emergence of psychotic disorders like schizophrenia.
Pollution seems to be an inescapable side-effect of humanity’s development—thus far, at least—and while scientists and environmentalists know it’s dangerous, some health-related consequences are just now beginning to emerge. Two years ago, the University of Rochester Medical Center conducted a study in which they tested the effect of air pollution on the development of the brain (1). By subjecting young mice to the air pollution that one would typically experience in a mid-sized US city during rush hour, scientists found that the brain became severely inflamed. As a result, white matter around the lateral ventricles (the part of brain that’s associated with schizophrenia and autism in humans) was underdeveloped, and there were also elevated levels of the neurotransmitter glutamate (which is also linked to schizophrenia and autism).
Even more disturbing, these mice were only exposed to this pollution for 4 hours a day over a total span of 8 days. The study was conducted 2 weeks after birth (which is a crucial developmental period for these animals), showing how delicate an organ the brain really is, especially in the early stages of its growth (1). If the results of this study are accurate, this means that young children in the United States and Europe are at an increased risk of developing schizophrenia, as these countries are two of the world’s largest producers of nitrogen dioxide – the poisonous gas emitted by cars and industrial buildings (3). The two graphics below show an alarming overlap of areas in the United States that have high levels of pollution and locations of adults in the United States who have serious mental illnesses. In both maps, darker reds and oranges represent a high density of either pollution or mental disorders, both of which are concentrated in south-eastern states like Tennessee, Kentucky, and Arkansas, as well as in the Midwest near Utah.
Furthermore, an online study in Environmental Health concluded that tetrachloroethylene (a chemical liquid primarily used to clean clothes) could very well contribute to mental illnesses like bipolar disorder and schizophrenia. The study observed people who were exposed to tetrachloroethylene-contaminated drinking water in Cape Cod during childhood, and found that they were twice as likely to develop disorders like schizophrenia (6). This contaminant is extremely mobile in water, but difficult to clean up, and when ingested, is thought to permeate the blood-brain barrier and disrupt fatty acids and neuronal receptors in the brain. In light of these studies, recent crises like the water contamination in Flint, Michigan and the natural gas leak in southern California become all the more frightening, given that our mental health could be at stake.
Specialists in all fields are desperately searching for the cause behind the steadily rising rates of mental disorders, and especially in the nutritional field, some conclude that poor diet can lead to these types of disruptions in brain chemistry. Because something as simple as sensitivities to foods affect dopamine and glutamate levels (two hormones that are imbalanced in schizophrenic patients), it would make perfect sense that nutrition plays a crucial role in mental health, as well as physical (7). As one of the most obese countries in the world, 69% of Americans are overweight. Northwestern Medicine and Northeastern Illinois University found that 95% of college students are not eating an adequate diet, and 60% don’t do enough physical activity to prevent weight gain; these paired with perpetual drinking and smoking have contributed to a recent spike in obesity on college campuses (8).
This year, sugar has replaced fat as the main scapegoat behind obesity and related physical illnesses. However, according to a study by the British Journal of Psychiatry, refined sugar is also linked to the emergence of mental illnesses like schizophrenia and depression (9). Scientists found that refined sugar suppresses the hormone BDNF (brain-derived neurotrophic factor), which is necessary for learning and memory and is found to be low in patients with schizophrenia. Refined sugar also leads to chronic inflammation, which is linked to the emergence of schizophrenia, as well.
While there have been countless studies outlining the correlation between obesity and schizophrenia, most state that schizophrenia causes weight gain due to stress and the side-effects of medications. However, another study in the British Journal of Psychiatry pointed out that while antipsychotic medication does cause weight gain, metabolic syndrome (a set of risk factors associated with obesity) affects 15% of schizophrenics before medication, as well as up to 30% of relatives with similar genetics, but without the disorder (10). Furthermore, there have been 4 large studies in the past several years that show a connection between motherhood obesity and offspring’s development of psychosis; results showed that children of obese mothers were significantly more likely to report hallucinations and schizophrenic tendencies by 21 years old (12).
Perhaps most interestingly, it’s been proven that diet can rapidly change the human gut microbiome, which is a Negative Effects of Sugar (11) collection of microorganisms that live inside the body and heavily influence digestion and immunity (13). In 2015, scientists analyzed the microbiome of patients with schizophrenia and found that it was drastically different than those without the disorder. Specifically, they found that those with schizophrenia had much higher levels of lactic acid bacteria, which are closely associated with chronic inflammation and thrive in environments with high levels of sugar (14).
Cannabis—more commonly called marijuana, weed, or pot—has a steadily-rising 18.1 million users, and is therefore the most frequently used illicit drug in America. According to a study by the University of Michigan, cannabis use among college students is at its highest point in almost three decades, given that 1 in 20 students smokes marijuana daily; in the early 1990s, that statistic was 1 in 50 (15). Combined with the facts that THC content is becoming more potent, synthetic versions are flooding the market, and children are starting to use it at a much younger age (often as young as 12), the link between cannabis and schizophrenia is definitely worth examining (16).
Scientists have found that THC (the psychoactive ingredient in marijuana) causes similar reactions in the brain as schizophrenia. Symptoms like paranoia, disassociation with reality, visual hallucinations, and difficulties distinguishing the passage of time regularly occur, which leads scientists to believe the two instances affect the brain similarly. Both cause parallel hormone releases, like dopamine and glutamine, as well as changes in brain chemistry. As a result, some studies conclude that cannabis may very well prompt psychotic disorders like schizophrenia, especially if someone is genetically predisposed, or starts using at a particularly young age (16).
However, other studies show that cannabis use is significantly higher in the schizophrenic community because patients are simply more likely to use it in the first place. One study in particular (Ferdinand et al.) found that children with prodromal psychotic episodes were more likely to smoke marijuana later on in their lives (17).
Nonetheless, whether the scientists believe that marijuana causes schizophrenia, or schizophrenia leads to marijuana, both agree on one thing: cannabis affects schizophrenic brains differently, and it definitely exacerbates symptoms by disrupting hormone levels, ultimately making the disorder worse (18).
This would also explain why the onset of schizophrenia happens when it does. A structural development occurs in the brain toward the end of adolescence, namely developmental changes in neurotransmitters. This would also explain why the onset of schizophrenia happens when it does. A structural and because the pituitary gland is enlarged in those who report psychosis, it’s likely that unbalanced hormonal levels are to blame (20). Drug use could exacerbate this imbalance, prompting or worsening the psychosis.
While schizophrenia might have its roots in genetic makeup, there are certain circumstances and habits that could possibly prompt or worsen symptoms. Although all Americans are potentially at an increased risk of developing a mental disorder like schizophrenia (because of high levels of pollution, the obesity epidemic, and the high national rate of cannabis use), college students should take extra precaution. In addition to a recent spike in obesity and marijuana use on college campuses, they also belong to the age bracket in which schizophrenic symptoms usually begin to emerge.