People with anxiety disorders may share measurable changes in brain chemistry related to choline, an essential nutrient associated with memory, mood, cell structure, and neural signaling.
A study from the University of California, Davis Health found that people diagnosed with anxiety disorders had lower choline levels in their brains than people without anxiety. This discovery is molecular psychiatryin the journal Nature, provides a rare look at chemicals that may be associated with anxiety across several different diagnoses.
The researchers reviewed data from 25 previous studies that measured neurometabolites, chemicals involved in brain metabolism. Overall, the analysis included 370 people with anxiety disorders and 342 people without anxiety.
Consistent chemical signals in the brain
A notable discovery was choline. People with anxiety disorders had about 8% lower levels of this nutrient in their brains compared to a control group. This pattern was particularly pronounced in the prefrontal cortex, which helps control thoughts, emotions, decisions, and behavior.
“This is the first meta-analysis to show brain chemical patterns in anxiety disorders,” said co-author Jason Smukny, assistant professor in the Department of Psychiatry and Behavioral Sciences. “This suggests that nutritional approaches, such as appropriate choline supplementation, may help restore brain chemistry and improve patient outcomes.”
Choline (pronounced ko-ren) plays several important roles in the body. It helps form cell membranes and supports brain functions related to memory, mood regulation, and muscle control. The body can produce small amounts of choline on its own, but most of it must come from food.
Why anxiety disorders matter
Anxiety disorders are one of the most common mental health conditions in the United States. The study’s senior author, Richard Maddock, is a psychiatrist and research professor in the Department of Psychiatry and Behavioral Sciences. He is also a researcher at the University of California, 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 they affect the brain.
“Anxiety disorders are the most common mental illness in the United States, affecting approximately 30 percent of adults. Anxiety disorders can be debilitating, and many do not receive appropriate treatment,” Maddock said.
Anxiety disorders include generalized anxiety disorder, panic disorder, social anxiety disorder, and phobias.
How the brain processes fear and stress
Anxiety disorders are related to how the brain responds to stress, danger, and uncertainty. Two key areas are often involved: the amygdala, which helps create a sense of safety and threat, and the prefrontal cortex, which supports planning, decision-making, and emotional regulation.
When this system is working well, the brain is usually able to distinguish between manageable problems and serious threats. Anxiety disorders can disrupt that balance. Daily worries can overwhelm you and make it difficult to calm your body’s stress response.
Brain chemistry also plays a role. Anxiety disorders are thought to be related to changes in neurotransmitters such as norepinephrine, which is part of the body’s “fight or flight” response. Norepinephrine is often elevated in anxiety disorders, and researchers at the University of California, Davis suggest that this heightened arousal may increase the brain’s demand for choline.
For example, with generalized anxiety disorder, people may worry excessively about everyday events and have trouble controlling their nervousness and fear.
Measuring brain chemicals without surgery
Maddock and Smukny have long studied how brain chemistry relates to mental illness using proton magnetic resonance spectroscopy, also known as 1H-MRS.
This technique is non-invasive and is performed using an MRI machine. Instead of producing standard images of brain structures, 1H-MRS uses magnetic fields and radio waves to measure chemical levels in tissues.
Professor Maddock had previously found low choline levels in a study of panic disorder patients. This early research helped lead to a large meta-analysis by Smucny. Although the researchers expected a reduction in choline, the consistency of the results was striking.
“An 8% reduction may not seem like a big deal, but it’s important for the brain,” Maddock says.
The study also found reduced cortical NAA levels across brain regions after making several exclusions. NAA is thought to be a marker associated with neuronal health and function. But the clearest and most consistent signal was a reduction in choline-containing compounds across anxiety disorders.
Choline, diet, and mental health
Researchers believe that chronic fight-or-flight activity may increase the brain’s demand for choline. If the brain doesn’t get enough to meet its demands, choline levels can drop.
That doesn’t mean choline supplements are proven as a treatment for anxiety. Maddock stressed that the question remains open.
“We don’t yet know whether increasing choline in the diet helps reduce anxiety. Further research is needed,” Maddock said. He cautions that people with anxiety should not self-medicate with excess choline supplements.
Still, this discovery has sparked further interest in the relationship between nutrition and mental health. We already know that choline is important for the brain and nervous system, and many people in the United States don’t consume the recommended daily amount.
“People with anxiety disorders may want to review their diet to see if they are getting the recommended daily amount of choline. Previous studies have shown that most people in the United States, including children, are not getting the recommended daily amount,” Maddock said. “Some forms of omega-3 fatty acids, such as those found in salmon, may be particularly good sources of choline to the brain.”
What was added in subsequent research
Since the UC Davis study was published, the broader research picture remains interesting, but still unresolved. A related dietary study in adults suggests that increased choline intake may be associated with lower odds of depression, but the same study found no significant adjusted associations with anxiety or psychological distress.
That makes the results of the UC Davis brain imaging study particularly interesting. Although this indicates measurable chemical differences in the brain, it does not prove that low choline in the diet causes anxiety or that increasing choline will alleviate symptoms. Controlled trials will be needed to test whether changing choline intake changes brain chemistry and improves anxiety outcomes.
So far, the findings support a pragmatic but cautious message. Nutrition may be part of the anxiety puzzle, but it’s not a substitute for professional mental health care.
Foods that supply choline
Choline is found in several common foods. Rich sources include beef liver, eggs (especially egg yolks), beef, chicken, fish, soybeans, and milk.
This study highlights a possible biological link between anxiety and the nutrients the brain depends on every day. It also raises a larger question for future research: whether improving cholinergic status can help restore brain chemistry in people with anxiety disorders.
Researchers say they don’t yet know the answer. But the discovery gives scientists a clearer chemical target to study and gives people new reasons to focus on nutrients that support brain health.
