Excitotoxins are substances, usually amino acids, that stimulate taste receptors on the tongue. This greatly enhances our perception of a food’s flavor. Excitotoxins have no nutritional value and are only added to make food taste more irresistible to consumers. Despite being considered benign by food manufacturers, research shows that excitotoxins can have harmful health effects.
How do excitotoxins work?
Neuron receptors allow your brain cells to communicate with each other. When exposed to excitotoxins, neuron receptors in your brain fire much more rapidly than normal. This can go on for hours, which will either exhaust and weaken the neurons involved or kill them completely. And once a neuron has died, it will not come back. This damage is permanent.
Scientists have found this effect is particularly noticeable in the parts of the brain that control behavior, emotions, onset of puberty, sleep cycles and immunity.
Neurons will produce free radicals under the influence of excitoxins, which can harm other cells if left to circulate in your body. Your brain has protective functions that control any exposure to naturally-occurring excitotoxins. Antioxidants, such as vitamins C and E, will dispose of any excessive free radicals under normal conditions.
The problem comes with modern, refined food additives that contain unnaturally high amounts of excitoxins. These purified products will set off strong reactions in your neurons, which will release a lot of free radicals. If your body doesn’t have enough antioxidants to keep up, free radical production can easily reach dangerous levels.
In addition, certain excitotoxins, such as aspartame and monosodium glutamate (MSG), have been shown to cross the placenta in pregnant women. This could lead to impaired development of the fetal nervous system, including cerebral palsy or developmental disorders.
Common Excitotoxins and Their Effects
Various excitotoxins are used in a wide variety of prepared foods to enhance the flavor. Manufacturers consider them especially valuable in many low-fat and vegetarian products that may naturally have less flavorful ingredients.
Always read the ingredient label when you’re buying any prepared foods, even if they’re advertised as a healthy option. These are some of the most harmful excitotoxins to watch out for.
Aspartame / Aspartate – This is used as an artificial sweetener and sugar substitute. It’s also known by the brand names NutraSweet, Equal or Spoonful. You’ll see this additive in a lot of diet, sugar-free or diabetic products, such as sodas and other drinks, candies, yogurt, supplements or cereals.
Research studies have shown many potential adverse health effects from the consumption of aspartame. For instance, aspartame may trigger or worsen illnesses such as brain tumors, multiple sclerosis, epilepsy and seizures, Alzheimer’s disease, birth defects and diabetes.
In fact, 85 percent of all complaints registered with the US Federal Drug Administration are for adverse reactions to aspartame, including five reported deaths.
Monosodium Glutamate (MSG) – Japanese researchers first isolated MSG from the Japanese seaweed called kombu in 1908. The manufacturing process removes all the beneficial enzymes and minerals found in kombu until you’re left with highly concentrated monosodium glutamate.
A huge number of prepared foods contain MSG, such as many soups, chips, flavored crackers, soy sauces, salad dressings, fast foods, ready-made dinners and canned goods.
You may not be safe by simply avoiding the term “monosodium glutamate” listed on food package labels. Food manufacturers may also include additives such as:
- Hydrolyzed vegetable protein
- Textured vegetable protein
- Natural flavoring
Each of these additives may contain from 12 to 40 percent MSG. Also be suspicious of restaurants that advertise they don’t add MSG to their food. They may not need to, many of the products they get from their suppliers are likely already full of this excitotoxin.
Many people report experiencing migraine headaches or other reactions after eating MSG. This is sometimes known as MSG symptom complex. Dr. George R. Schwartz, author of In Bad Taste: The MSG Syndrome, groups symptoms that may result from MSG consumption into three categories:
- Allergic symptoms – e.g. rash, hives, asthma, or sneezing.
- Peripheral symptoms – e.g. jaw tightness, headache, rapid heartbeat, diarrhea and stomach cramps.
- Central (Brain) symptoms – e.g. depression, insomnia, confusion and paranoia.
MSG sensitivity can also develop over time. Regular consumption of MSG will create more nerve cells that are sensitive to it. And the more sensitive nerve cells you have, the more likely you are to react negatively to MSG. Dr. Russell Blaylock called this our “threshold of sensitivity” in his book Excitotoxins: The Taste that Kills.
Studies on mice found that MSG consumption could lead to obesity, reduced physical activity, reduced pituitary gland function, shrunken ovary size, delayed puberty and elevated levels of the hormone corticosterone.
Cysteine – This excitotoxin reacts with sugars and results in meaty and savory flavors when used as a flavor enhancer. It is usually called L-cysteine on food labels, and may also be used in breads or sold in health food stores as a supplement.
L-cysteine is typically produced from either human or pig hair, or duck feathers. This means it is generally not a vegetarian or vegan food additive.
Similar to other excitotoxins, L-Cysteine can produce brain damage by killing neurons.
High cysteine levels are also associated with Parkinson’s and Alzheimer’s disease.
Casein – Casein is a protein found in milk. Cheese is naturally high in casein. It is also added to some non-dairy creamers and soy cheeses, as well as fitness products to increase the protein levels.
Twenty percent of casein is made up of glutamic acid, the less-refined form of MSG. This makes casein a great flavor enhancer, but it can also contribute to glutamate sensitivity.