People with anxiety disorders may share a measurable change in brain chemistry involving choline, an essential nutrient tied to memory, mood, cell structure, and nerve signaling.
Research from UC Davis Health found that people diagnosed with anxiety disorders had lower levels of choline in the brain than people without anxiety. The finding comes from a study published in Molecular Psychiatry, a Nature journal, and offers a rare look at the chemistry that may be connected to anxiety across several different diagnoses.
The researchers reviewed data from 25 previous studies that measured neurometabolites, the chemicals involved in brain metabolism. Altogether, the analysis included 370 people with anxiety disorders and 342 people without anxiety.
A Consistent Chemical Signal in the Brain
The standout finding was choline. People with anxiety disorders had about 8% lower levels of this nutrient in the brain compared with those in the control groups. The pattern was especially clear in the prefrontal cortex, a brain region that helps regulate thought, emotion, decision making, and behavior.
“This is the first meta-analysis to show a chemical pattern in the brain in anxiety disorders,” said Jason Smucny, co-author and an assistant professor in the Department of Psychiatry and Behavioral Sciences. “It suggests nutritional approaches — like appropriate choline supplementation — may help restore brain chemistry and improve outcomes for patients.”
Choline (pronounced kō-lēn) plays several important roles in the body. It helps form cell membranes and supports brain functions involved in memory, mood regulation, and muscle control. Although the body can make a small amount on its own, most choline must come from food.
Why Anxiety Disorders Matter
Anxiety disorders are among the most common mental health conditions in the United States. Richard Maddock, senior author of the study, is a psychiatrist and research professor in the Department of Psychiatry and Behavioral Sciences. He is also a researcher at the UC Davis Imaging Research Center, where scientists use magnetic resonance imaging (MRI) methods to study brain health.
Maddock has spent decades treating people with anxiety disorders and studying how these conditions affect the brain.
“Anxiety disorders are the most common mental illness in the United States, affecting about 30% of adults. They can be debilitating for people, and many people do not receive adequate treatment,” Maddock said.
Anxiety disorders include generalized anxiety disorder, panic disorder, social anxiety disorders, and phobias.
How the Brain Processes Fear and Stress
Anxiety disorders are connected to the way the brain responds to stress, danger, and uncertainty. Two key regions are often involved: the amygdala, which helps shape the sense of safety or threat, and the prefrontal cortex, which supports planning, decision making, and emotional control.
When this system is working well, the brain can usually separate manageable problems from serious threats. In anxiety disorders, that balance can shift. Everyday concerns may feel overwhelming, and the body’s stress response can become difficult to calm.
Brain chemistry also plays a role. Anxiety disorders have been linked to changes in neurotransmitters, including norepinephrine, which is part of the body’s “fight-or-flight” response. Norepinephrine is often elevated in anxiety disorders, and the UC Davis researchers suggest that this heightened arousal may increase the brain’s demand for choline.
In generalized anxiety disorder, for example, people may worry excessively about ordinary events and struggle to control nervousness or fear.
Measuring Brain Chemicals Without Surgery
Maddock and Smucny have long studied how brain chemistry is connected to mental illness using proton magnetic resonance spectroscopy, also known as 1H-MRS.
This technique is noninvasive and is performed with an MRI machine. Instead of producing a standard image of brain structure, 1H-MRS uses magnetic fields and radio waves to measure chemical levels in tissue.
Maddock had previously seen low choline levels in studies of people with panic disorder. That earlier work helped lead to the larger meta-analysis with Smucny. Even though the researchers expected to see reduced choline, the consistency of the result stood out.
“An 8% lower amount doesn’t sound like that much, but in the brain it’s significant,” Maddock said.
The study also found reduced levels of cortical NAA across brain regions after some exclusions. NAA is often considered a marker related to neuronal health and function. However, the clearest and most consistent signal was the reduction in choline-containing compounds across anxiety disorders.
Choline, Diet, and Mental Health
The researchers think that chronic fight-or-flight activity may raise the brain’s need for choline. If the brain cannot take in enough to meet that demand, choline levels may drop.
That does not mean choline supplements are a proven treatment for anxiety. Maddock emphasized that the question remains open.
“We don’t know yet if increasing choline in the diet will help reduce anxiety. More research will be needed,” Maddock said. He cautions that people with anxiety should not self-medicate with excessive choline supplements.
Still, the finding adds to growing interest in the relationship between nutrition and mental health. Choline is already known to be important for the brain and nervous system, and many people in the United States do not get the recommended daily amount.
“Someone with an anxiety disorder might want to look at their diet and see whether they are getting the recommended daily amount of choline. Previous research has shown that most people in the U.S., including children, don’t get the recommended daily amount,” Maddock said. “Some forms of omega-3 fatty acids, like those found in salmon, may be especially good sources for supplying choline to the brain.”
What Later Research Adds
Since the UC Davis work was published, the broader research picture has remained intriguing but not settled. Related dietary research in adults has suggested that higher choline intake may be linked with lower odds of depression, but the same study did not find a significant adjusted association with anxiety or psychological distress.
That makes the UC Davis brain imaging result especially interesting. It points to a measurable chemical difference inside the brain, but it does not prove that low dietary choline causes anxiety or that increasing choline will relieve symptoms. Controlled trials would be needed to test whether changing choline intake can alter brain chemistry or improve anxiety outcomes.
For now, the findings support a practical but cautious message: nutrition may be one piece of the anxiety puzzle, but it is not a substitute for professional mental health care.
Foods That Provide Choline
Choline is found in several common foods. Rich sources include beef liver, eggs (particularly the yolk), beef, chicken, fish, soybeans and milk, among others.
The study highlights a possible biological link between anxiety and a nutrient the brain depends on every day. It also raises a larger question for future research: whether improving choline status could help restore brain chemistry in people with anxiety disorders.
For now, researchers say the answer is not yet known. But the discovery gives scientists a clearer chemical target to investigate and gives people another reason to pay attention to the nutrients that support brain health.