Balancing Glutamate for a Healthy Brain

By Natalie Collier, MScN

What is Glutamate

Glutamate is the most common excitatory neurotransmitter and most abundant amino acid in the brain. Glutamate is necessary for normal brain function, learning and memory. Although glutamate is a necessary neurotransmitter, more of it is not better. Too much glutamate wreaks havoc in the brain exciting cells to their death in a process known as excitotoxicity. High levels of glutamate have been linked to increased pain. Excitotoxicity has been associated with stroke, Alzheimer’s Disease, seizures and autism.  

Where do we get Glutamate in the Diet?

The body can manufacture its own Glutamate. Therefore, there is no dietary recommendations or requirements for glutamate. Glutamate is both naturally occurring and synthetic in our food supply. There are two types of dietary sources for glutamate; bound glutamate and free glutamate. Bound glutamate is present in various amounts in all foods that contain protein. Most people do not react to bound glutamate. However, some people benefit from reducing high glutamate foods. Free glutamate is not bound to other amino acids making it a very concentrated and stimulating source of glutamate. An example of a free glutamate is MSG, or monosodium glutamate, a synthetic form of glutamate. 

MSG is a synthetic food additive and flavor enhancer found in almost all processed foods and some restaurant cuisine to give food umami flavor (the fifth basic taste). All MSG should be avoided completely as it has been linked to endocrine disruption, migraines, heart palpitations and a cluster of symptoms known as “Chinese Restaurant Syndrome.” There are many sources of hidden free glutamate even in “healthy” snacks found at natural food stores. Watch for ingredients such as “hydrolyzed” foods like “hydrolyzed protein”, yeast extract, monopotassium glutamate, textured protein, soy protein and/or whey protein. These all can be hidden sources of MSG. Some otherwise healthy foods are naturally high in free glutamate including oysters, wheat/gluten, tomatoes, potatoes, mushrooms, aged cheeses and peanuts. In certain individuals the nerve cell can be more sensitive to glutamate and these foods should be limited in those populations.

Glutamate and GABA

GABA and Glutamate have an important relationship as GABA is manufactured from glutamate. Glutamate is the major excitatory neurotransmitter while GABA works as the major inhibitory neurotransmitter. They help keep the other balanced. If Glutamate had a personality in excess it would be angry, irritating and irrational. If GABA had a personality type it would be cool, calm and carefree. We can see how these qualities make them most effective as a team. When one or the other takes power over the other, the brain becomes troubled. 

When Glutamate is Low

Low glutamate is uncommon. Symptoms of low glutamate may include insomnia, concentration, mental exhaustion and low energy, but is also a signal the gastrointestinal tract may be in distress. Supplementing with glutamine and including foods that are naturally rich in glutamate will help to restore levels of glutamate. 

When Glutamate is Elevated

Symptoms of high glutamate may include headaches, anxiety, irritability, restlessness and ADHD-like symptoms. MSG and other food additives containing glutamate, should be strictly avoided. The ingredients below are examples of food additives that contain glutamate:

• Anything hydrolyzed
• Sodium caseinate
• Yeast extract
• Autolyzed yeast
• Whey Protein
• Soy protein
• Soy protein concentrate
• Soy sauce
• Gelatin
• Glutamic acid

When glutamate is elevated consider also reducing foods that are naturally high in free glutamate such as wheat/gluten, barley, peanuts, diet drinks. Foods to focus on may include: pasture-raised chicken and eggs, legumes, wild fish, quinoa, avocados, leafy greens, rice, sweet potatoes, whole fruits, fresh or dried herbs and spices. Support GABA levels (put link to GABA article) through proper diet, targeted supplementation and lifestyle modifications. For example, practicing yoga and meditation has been shown to be beneficial for GABA levels.