From Ron Hoffman, MD.
I just got back from the American Nutrition Association Annual Summit in San Diego. The theme was the impact of nutrition on mental health. It was an awesome assembly of great researchers and speakers, and it’ll provide me with fodder for many Intelligent Medicine articles and podcasts in the new year.
Presenter after presenter laid out the stark fact: It’s undeniable we’re in the midst of a mental health crisis. In addition to diagnosable psychiatric conditions, we’re increasingly angry and impulsive, as is reflected in crime stats, our political discourse, and raucous social media.
Drugs and psychotherapy have not been conspicuously successful at stemming the tide of mental disorders; complete resolution of psychiatric conditions with standard care is more the exception than the rule.
Much of this is fueled by societal factors, but it’s arguable that poor diets play a significant role. Ultra-processed foods laden with sugar, refined seed oils, chemical additives and carby snacks bereft of nutrients critical for brain health are all pro-inflammatory. Studies have confirmed that inflammation impairs decision-making and heightens impulsivity.
And, when it comes to food selection and consumption, what does impulsivity lead to? Disordered eating, poor choices and addictive behaviors, further perpetuating a vicious cycle toward progressive mental impairment.
Sophisticated neuro-imaging now confirms that obesity, in and of itself, is associated with brain changes, and given the high percentage of westerners who now meet the criteria for excess weight, small wonder that we’re seeing a plethora of psychiatric disorders as well as accelerated progression to dementia.
Several of the speakers highlighted the role of the microbiome in brain health. The gut-brain axis, as it’s called, is a busy two-way highway: Impulses from the brain—whether benign or harmful—affect digestion. Stress can change the composition of the microbiome, the bacteria in our intestines that “talk” to the brain via chemical messages. Stress can even alter intestinal permeability, promoting “leaky gut” which predisposes to endotoxemia, autoimmunity, and hampered brain function.
Conversely, the GI tract exerts a profound impact on the brain. A new science has emerged around the concept of “psychobiotics”—probiotics that influence mood. Animal studies show that fecal transfers from extroverted animals can make introverted animals—the rodent equivalent of humans with depression or social phobia—into gregarious critters.