Food Sensitivities and Anxiety

  • The Brain is highly affected by food and is sensitive to what we eat

  • Immune reactions against food can alter cortisol levels and brain activation levels

  • When the brain is abnormally activated over an extended period of time, it will “learn” that activation pattern

  • Having a continued alertness response in the brain eventually becomes anxiety

There is growing evidence that food sensitivities are a common cause of anxiety disorders. It is, however, not commonly appreciated by the public. David Perlmutter, M.D. comments on this in his popular new book “Grain Brain“:

“The idea that brains are sensitive to what we eat has been quietly circulating in our most prestigious medical literature recently. This information begs to be known by the public, which is increasingly duped by the food industry that sells foods commonly thought to be nutritious.” 

While his book focuses on gluten from grains, the concepts are the same for any food that an individual reacts to.

The real question most people with anxiety have is how can what I eat cause my brain to not work right? The answer comes from examining a few well established concepts about the human body. An immune reaction against food begins in the digestive tract, but the reaction occurs throughout the body including the brain. This is why when we have a cold which is a viral infection in the sinuses and chest, we ache all over. The chemical inflammatory attack our immune system mounts against it is systemic.

Another part of the immune activation is that it alerts the brain by causing a stress response. The stress response is really a fear response which causes a high amount of alertness in the brain by raising the levels of the hormone cortisol. This alertness is designed to be a short term process. Unfortunately with a food sensitivity the immune reaction becomes chronic, and the brain begins to become over stimulated.

The best trait about the brain is that it learns. If you stimulate it with hearing and seeing French over time, neurons or brain cells from connections with other neurons called synapses. A complex connection of many neurons become functionally connected, in essence becoming the “wired program” that is the memory of French.

The worst trait of the brain, however, is also that it learns. An ongoing immune problem that secondarily causes cortisol elevation and ongoing alerting of the brain will begin to cause a learning pattern the same as studying French does. Sustained cortisol activation of the brain eventually trains the brain to react with too much alertness to everyday, non-stressful events. This perception is one of anxiety.

Anxiety patterning in the brain may relate to how the brain processes information. Visual, sound and other inputs are first processed in the back of the brain. They must be processed to the front of the brain through several areas that help with processing to form what we think we actually see and hear. Some of that information is processed through the right side of the brain and some through the left.

Generally the left side of the brain processes more analytically, while the right side processes more emotionally. With normal brain processing most information gets processed both through the left and right sides of the brain resulting in a balance of analytical (what do I think) and emotional processing (how do I feel). The alert state of the brain caused by frequent and sustained cortisol activity causes a shift to more right-sided processing. Once the brain learns this, normal things begin to activate the brain more emotionally which generates anxiety.

It is good to have a little anxiety when you see someone approaching with a handgun. The alertness is needed for the “fight or flight response”. However, we should not get the same reaction simply answering the phone at work.

With time the brain will try to shut down some of the excessive anxiety pattern causing the process to be “too flat” at times. This is the clinical expression of depressive traits. In the classic sense disorders of mood typically transition through stages:

Supporting this continuum of anxiety and depression is the common management of anxiety or depression with the same medications.


The current understanding is:

  1. The brain is highly affected by food

  2. Immune reactions against food alter cortisol levels and brain activation levels

  3. When the brain is abnormally activated over an extended period of time, it will “learn” that activation pattern

  4. A sustained alertness response in the brain eventually becomes anxiety


Dr. Perlmutter is correct in his comment that the brain is sensitive to what we eat. Fortunately by finding the trigger of this abnormal brain activation the pattern of anxiety/depression can often be reversed. To quote the slogan from one of our American organizations, the mind is a terrible thing to waste.

Rather than the last resort as is common, anxiety should call for the screening for food sensitivity. Anxiety feeds on itself, and time is the worst things one can give it. While it can be softened by a drug, it cannot be cured that way.