A non-invasive imaging technique, 1H-MRS, can detect chemicals in different parts of the brain. Choline is represented by “Cho” in the above graph. Credit: UC Regents.
Levels of choline is 8% lower in the brains of those with generalised anxiety disorder, panic disorder and social anxiety disorder.
People with anxiety disorders have lower levels of choline in their brains, according to research from UC Davis Health.
The study analysed data from 25 studies. The researchers compared the levels of neurometabolites — chemicals produced during brain metabolism — in 370 people with anxiety disorders to 342 people without anxiety.
They found the level of choline — an essential nutrient — was about 8% lower in those with anxiety disorders.
Choline is vital for cell membranes and brain functions like memory, mood regulation and muscle control. The body makes a small amount, but most must come from food.
The evidence for low choline was especially consistent in the prefrontal cortex, the part of the brain that helps control thinking, emotions and behaviour.
Study co-author Jason Smucny, who is an assistant professor in the Department of Psychiatry and Behavioral Sciences, said: “This is the first meta-analysis to show a chemical pattern in the brain in anxiety disorders.
“It suggests nutritional approaches — like appropriate choline supplementation — may help restore brain chemistry and improve outcomes for patients.”
Many animal-based products are rich in choline, but it is also found in vegetables and seeds. Created with Microsoft CoPilot. Source of data: NIH Office of Dietary Supplements. Credit: UC Regents.
Anxiety disorders affect about 30% of adults
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, which uses magnetic resonance imaging (MRI) techniques to study brain health.
Maddock spent decades in clinical practice treating patients with anxiety disorders and conducting research on these conditions.
He said: “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.”
Anxiety disorders include:
Brain interactions affect anxiety
Anxiety disorders are linked to how different parts of the brain — like the amygdala, which influences our sense of safety or danger, and the prefrontal cortex, which is involved in planning and decision-making — respond to stress or potential threats.
Anxiety disorders are also linked to imbalances in neurotransmitters. For example, norepinephrine — part of the body’s ‘fight-or-flight’ response — is often elevated in anxiety disorders.
Normally, the brain can tell the difference between potential threats that are manageable and those that are not.
In anxiety disorders, manageable threats can seem overwhelming. For example, with generalised anxiety disorder, people worry excessively about everyday things and have trouble controlling their worries or feelings of nervousness.
Non-invasive technique identifies chemical levels in the brain
Maddock and Smucny have spent years studying brain chemistry and its association with mental illness using a non-invasive medical imaging technique known as proton magnetic resonance spectroscopy, or 1H-MRS.
The measurements are made using an MRI machine.
1H-MRS uses the magnetic fields and radio waves of an MRI to analyse the body. However, instead of creating an image of the body, it provides data about the chemicals that are present in the tissue.
Maddock had noticed low levels of choline in his earlier studies of patients with panic disorder. He decided to conduct a meta-analysis with Smucny. And even though they thought they would find low choline, he was still surprised by the results.
He said: “An 8% lower amount doesn’t sound like that much, but in the brain it’s significant.”
Most people don’t get enough choline
The researchers think the high fight-or-flight activity experienced in anxiety disorders may increase choline demand, lowering its levels.
Maddock said: “We don’t know yet if increasing choline in the diet will help reduce anxiety. More research will be needed.”
He cautioned that people with anxiety should not self-medicate with excessive choline supplements, but he noted a healthy diet is essential for all aspects of health, including mental health.
Maddock said: “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 US, including children, don’t get the recommended daily amount.
“Some forms of omega-3 fatty acids, like those found in salmon, may be especially good sources for supplying choline to the brain.”
Other foods rich in choline include beef liver, eggs (particularly the yolk), beef, chicken, fish, soybeans and milk, among others.
The study is published in Molecular Psychiatry.
