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Fibromyalgia Basics

Removing Additives Improves Symptoms

Trying to figure out which foods could be making your fibromyalgia symptoms worse is a daunting task. A better approach would be to eliminate a few known offenders—if only you knew what they were! A study headed up by Kathleen F. Holton, Ph.D., M.P.H., of Oregon Health and Science University in Portland, could help reduce your dietary guessing-game.

Dietary Toxins

Consuming foods with flavor-enhancing additives can overstimulate your nerves to the point of being toxic. Everyone has heard of MSG (monosodium glutamate), but did you know that there are many other forms of this additive that can be bad for you too? In addition, aspartate and cysteine are two other culprits that you need to avoid. 

All three compounds—glutamate, aspartate and cysteine—are amino acids, and the natural ingredients in protein. It’s okay to consume them in unprocessed protein sources because they are bound together with other amino acids essential to the body. In their bound form, the concentration of these three substances does not get very high in the bloodstream, preventing them from doing harm.

On the other hand, when these three compounds are added as flavor-enhancers to processed foods, they are not bound to protein and their blood levels can rise rapidly. In fact, they are used for their ability to quickly stimulate the neurons in your tongue to make bland foods taste better. These additives likely activate the nerves along your digestive system as well, contributing to irritable bowel symptoms. Also, blood glutamate levels are known to be linked to greater fibromyalgia muscle pain.1 

Mind Control

Fibromyalgia is more than achy muscles and a digestive disorder. Your central nervous system magnifies pain and contributes to symptoms of fatigue, sleep disorder, fibrofog, and alterations in mood. It’s the job of the blood-brain barrier to protect your brain from toxins in the bloodstream, but not all areas have this barrier and, in some places, it may be broken in fibromyalgia.

“Glutamate freely enters brain regions that lack a blood-brain barrier,” says Jerry D. Smith, Pharm.D.2 The hypothalamus is a particularly vulnerable area, which helps regulate pain and sleep. In addition, the barrier can be eroded during stress, infections, or when the immune system is activated. Given that glutamate is high in the brain and spinal fluid of fibromyalgia patients and it’s linked to pain, are additives in your diet partly to blame? 3

Studies show that glutamate is elevated in the bloodstream and the gastrointestinal tract, and it is known to be capable of sensitizing nerve endings to cause pain.4 So, why ingest more of this nasty chemical if you might be able to avoid it, or at least reduce it to reduce your fibromyalgia symptoms?

Treatment Trial

To answer this question, Holton conducted a one-month treatment trial eliminating additives containing glutamate, aspartate, and cysteine.5 The study involved 37 fibromyalgia patients and she provided diet-training sessions and counseling to be sure participants were eating foods free of these acid-containing additives (they go by many names, including MSG and Aspartame).

Holton monitored the patient’s symptoms throughout the one-month trial and additionally for three consecutive mornings, where everyone was given a glass of juice to drink. Unknown to the patients, half of the drinks contained a typical daily dose of MSG. Quite often in treatment trials, fibromyalgia symptoms improve because patients understandably want to feel better. However, giving some patients glutamate at the end of the study helped Holton confirm if the effects of the trial were truly due to eliminating the additives.

Symptom Benefits

Of the thirty-seven patients, 84 percent reported a greater than 30 percent reduction of symptoms. These results are better than those of any of the FDA-approved drugs for fibromyalgia. On average, eleven of the fibromyalgia and irritable bowel syndrome symptoms remitted.

The next step in the study looked at the impact of adding MSG back into the diet. “Most participants (73 percent) reported the onset of symptoms during the evening hours of the first day of the MSG challenge or the following morning,” says Holton. “Symptoms worsened over time, peaking on day three.”

In fact, fibromyalgia symptoms seemed to come back with a vengeance compared to the patients who did not get the MSG-containing juice drink (the placebo comparison group). “All fibromyalgia symptoms returned more frequently during MSG challenge as compared to placebo challenge,” says Holton.

An important point made by the study was the practical and mildly restrictive nature of the diet. In fact, most patients continued to eliminate the additives after the trial was over. And one can’t overlook the significant improvement in all but six of the patients, providing strong evidence that glutamate and similar additives are making your fibromyalgia symptoms worse.

“Dietary manipulation is a relatively simple and low-cost non-pharmacological intervention,” says Holton. If you suspect that glutamate is exacerbating your fibromyalgia, it might be time to act.

Getting Started

Reducing your intake of glutamate-containing food is important, but challenging. Fast foods, chips, frozen foods, and canned soups are more likely to contain glutamate without being regulated to disclose the additive in their product. So, in addition to Horton’s “Foods to Avoid” list, you should be aware of the “other” names of glutamate-containing foods.

Until you become familiar with both lists, bring a copy of them with you to the grocery store. Reading labels is time-consuming, but after a few shopping trips, you will become familiar with the foods or products on both “do not eat” lists.

If you are able to work with a nutritionist, an excellent article by Holton on “The role of diet in the treatment of fibromyalgia” may help. It was published in 2016 in the journal, Pain Management, and is available to individuals for free. Click here to download the article (click on the Future Medicine logo) and hand it to your nutritionist.

Foods to Avoid

Below is a list of food items on Holton’s “do not eat” list:

Protein powder/shakes
Body building supplements
Spice mixes or seasoning packets
Marinades purchased at grocery store
Boxed foods including seasoning packets
Canned goods (canned soup, chili, etc.)
Frozen meals
Packaged spaghetti/tomato sauce
Asian prepackaged foods
Soy sauce
Other Asian sauces (like oyster sauce, etc.)
Worcestershire Sauce
Seasoned nuts
Chips (except plain tortilla or potato chips)
Crackers (excluding plain Triscuits)
Salad dressing or salad dressing mix
Caesar salad dressing
Parmesan cheese
Sausage, pepperoni, bacon, ham
Hot dogs; deli meat
Equal (Aspartame sweetener)
Diet soda or other diet drinks
Chewing gum
Breath mints
Vitamins or medication in gelatin capsules
Vitamins/medication containing Aspartame
Sugar-free candy
Jello or Jello pudding
Gelatin candy (Gummy Worms, Skittles, etc.)
Sunny Delight or vegetable juice
Reduced calorie yogurt
Regular flavor yogurt

Other Names for Glutamate

Yeast extract (bakery items, canned fish/meat)
Calcium or sodium caseinate (coffee creamers, instant cream soups)
Yeast food or nutrient (certain wines, cider, beer)
Textured protein (meat substitutes)
Soy protein, Concentrate, Isolate (breads, cookies, baked goods)
Whey protein (Ricotta cheese)
Vestin (another name for MSG)
Ajinomoto (Japanese name for MSG)
Anything “Hydrolyzed” often contains glutamate

1. Bazzichi L, et al. Clin Biochem 42:1064-70, 2009.
2. Smith JD, et al. Ann Pharmacother 35:702-6, 2001.
3. Harris RE, et al. Arthritis Rheum 58:903-7, 2008.
4. Clos-Garcia M, at al. EBioMedicine 46:499-511, 2019.
5. Holton KF, et al. Clin Exp Rheumatol 30(Suppl 74):S10-S17, 2012.
6. Holton K. Pain Manag 6(4):317020, 2016.