Content Library Articles Is Our Modern Diet Behind Our Mental Health Crisis?

Is Our Modern Diet Behind Our Mental Health Crisis?

Is Our Modern Diet Behind Our Mental Health Crisis?

Mental health problems and chronic disease have something crucial in common. Most doctors and patients don’t realize the connection, so they focus on treating the symptoms. Few know that the real solution lies in identifying the root cause. And the root cause is often the same for these two health crises. The culprit? The industrial American diet.

As I’ve treated patients for a multitude of physical conditions over the years, I saw that changes in their diet also resolved behavioral, mood, memory, or attention problems. I wrote about it several years ago in The UltraMind Solution and most recently in Food Fix, an exposé on the food industry.

The harmful effects of our nutritionally toxic and depleted food environment are widespread. Children struggle with intellectual development, ADHD, and behavioral problems. More and more adults suffer from panic attacks, crippling depression, cognitive decline, and chronic disease. And prisons are overflowing with criminals. Our national security is even at risk as many young adults are not fit to fight or eligible for service because of their mental or physical health. Overall diet quality, high sugar loads, and rampant nutritional deficiencies (including omega-3 fats, zinc, magnesium, vitamin D, and B vitamins) all drive behavior problems and mental health issues. It’s an injustice we cannot ignore. And you won’t when you realize how extensive the damage is.

The achievement gap

Mental health issues are starting earlier and earlier. One in six children has a neurodevelopmental disorder. More than one in ten children have ADHD. Depression, learning disabilities, and behavioral problems are rampant in schools. School nurses have to contend with boxes of prescription medications they have to dole out to kids during the school day. It’s common to hear Americans lament our low global standing in academic performance. We are thirty-first in math, reading, and science in the world.

This phenomenon of poor school performance in kids with health issues, poor diets, obesity and diabetes, is called the achievement gap. The CDC report health and academic achievement documents the clear link between poor nutrition and academic performance, including lower test scores, lower grades, poor cognitive function. Lack of fresh fruits and vegetables and vitamin and mineral deficiencies lead to the same problems. How can we expect kids to learn and function when they are hungry, skip breakfast, or go to school with a bottle of soda and a bag of chips? The state of nutrition in most schools doesn’t help—cafeterias peddle the food industry’s biggest brands of junk food for lunch and snacks. The result, according to the journal Pediatrics, is that kids are inattentive, disruptive, late, or absent. Food drives many of these problems.

The average kid in America consumes 34 teaspoons of sugar a day. The cognitive and behavioral effects of sugar in children are well documented. Kids literally bounce off the walls. Ever been to a birthday party where chaos ensues in the aftermath of a sugar binge? We are literally destroying the intellectual capital of our youth, with broad consequences for our whole society. In fact, we are raising the first generation of Americans who will live sicker and die younger than their parents.

Not only that, but special education costs are also skyrocketing across the country. In San Diego, the costs for special education are $1 billion of a $5 billion overall school budget. The number of kids needing special education has grown 19 percent since 2012, while overall school enrollment has grown by 2 percent.

While multiple causes play a role, the majority of cognitive dysfunction in kids can be linked to poor nutrition. Iron deficiency is common, leading to lower dopamine function and impaired concentration. Vitamin and mineral deficiencies including B vitamins, iodine, zinc, and vitamin E are linked to worse cognitive abilities and poor concentration.

Violence & crime

Science proves that food affects our hormones, brain chemistry, nutrient status, and other chemical and biological functions. In other words, what we eat changes our thinking, mood, and behavior. So it’s no wonder food has been linked to mental health and violence. Consider the following research:

  • Junk food makes kids act violently—bullying, fighting—and suffer more psychiatric distress, including worry, depression, confusion, insomnia, anxiety, aggression, and feelings of worthlessness.
  • In one study “Impact of Nutrition on Social Decision Making,” scientists fed two groups different breakfasts. One group got a high-carb breakfast, the other a high-protein, low-carb breakfast. The high-carb group was more likely to engage in “social punishment” behavior such as negative comments and actions toward others in structured behavioral experiments. Now, consider that most Americans eat dessert for breakfast, full of sugar and carbs—cereal, muffins, bagels, sugared coffees, pancakes, French toast, oatmeal—this does not make for a very nice society.
  • Those who consume high levels of refined oils (currently more than 10 percent of our diet and found in all ultraprocessed foods) and low levels of omega-3 fats from fish have higher rates of depression, suicide, and homicide. Our consumption of these refined oils (mostly soybean oil) went up 248 percent from 1970 to 2010.

Is there hope?

That research should concern you. Every meal is more than a simple choice of your daily fuel. It is also the determining factor in your mental (and physical) health. The good news is that a change in diet can change behavior to the positive extreme.

I recall walking into my office one day to find a handwritten letter from a violent criminal still in prison. He said he’d read one of my books, changed his diet, and realized that what he’d been eating had driven his whole life of violence. Changing his diet transformed him. Studies have shown similar results.

  • One study of violent juveniles found that children given a vitamin and mineral supplement reduced violent acts by 91 percent compared to a control group. These kids were deficient in iron, magnesium, B12, folate—all needed for proper brain function.
  • Another experimental study of 3,000 incarcerated youth replaced snack foods with healthier options and dramatically reduced refined and sugary foods. Over the twelve-month follow-up, antisocial behavior dropped by 21 percent, assaults decreased 25 percent, and the use of restraints was reduced by 75 percent.
  • In one double-blind randomized controlled trial, researchers found a 37 percent reduction in violent crime in those taking omega-3 fats and vitamin and mineral supplements. The author of the study said, “Having a bad diet is now a better predictor of future violence than past violent behavior.…Likewise, a diagnosis of psychopathy, generally perceived as being a better predictor than a criminal past, it is still miles behind what you can predict just from looking at what a person eats.”

Clearly crime and antisocial behavior arise from a complex set of social, economic, and environmental factors. But what if a big part of the solution to our increasing social strife, exploding rates of depression, mental illness, ADHD, bullying, violence, and crime, and overflowing criminal justice system is fixing our food system? Part of the solution is fixing broken brains by fixing the nutrition of those most at risk (and ideally all of us).

What needs to change

While not all mental illness is caused by food, it’s clear that poor nutrition can worsen mental health conditions. Population studies have found that more fruits and vegetables and less French fries, fast food, and sugar are associated with a lower prevalence of mental illness, and that junk food creates moderate to severe psychological distress. The good news is that interventional studies have shown that treatment of mental illness with diet works well (especially since most medications for mental illness don’t work that well, despite being the second biggest category of drugs sold).

Solving this problem is complex and requires addressing issues such as poverty, inequities, trauma, and violence. But a few changes can help integrate better nutrition into our society. I address them in depth in Food Fix if you want to read more.

  1. If you suffer from a mental health issue, get help from a Functional Medicine or integrative practitioner to help you address the dietary needs that will improve the health of your brain. You can also refer to my bookThe UltraMind Solution or my online documentary series Broken Brain for a detailed plan on how to fix your brain.
  1. The National Institutes of Health (NIH) should fund research to look deeply at the link between food and mental illness, especially clinical trials that help prove cause and effect. A lot of research already exists on nutritional psychiatry, but more is needed in order to help practitioners treat the root causes of mental illness, not just the symptoms.
  1. We need government reform in prison food and health care. The federal government, states, and cities that maintain jails or prisons can sign contracts with food service providers that have health in mind and on the menu. Some prisons such as the Michigan Department of Corrections and the Richard J. Donovan correctional Facility (San Diego) have already started programs that use local farms to provide healthier meals. It’s a no-brainer that health care should start paying for a food-as-medicine approach and programs to treat mental illness. Medical education must be reformed so doctors can apply nutritional psychiatry with their patients.
  1. We need more innovators (such as Big Green, Conscious Kitchen, Common Threads, and Brigaid) and parents around the country who are trying to get healthy food into schools and teaching children about nutrition. These programs need to be expanded and taken up as standard for all public and private school systems and local and federal policy. Real whole food should not be the privilege of a few schools and students. Real whole food that supports children’s development and learning must be a right for all children.

We must put an end to the damage from our standard diet. It is harming our intellectual capital, driving crime and violence, and increasing mental illness. It may seem that fixing some aspects of the food system would be hard, but if we target schools, prisons, and health care, we will make a drastic impact on health. These are not separate problems. They are one big, interconnected problem that can only be solved by multiple solutions across our food systems.


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