People who are intolerant of chemicals in everyday products or the environment often find their problems ignored or brushed aside by other people, even their doctors.
Over the past 30 years I've routinely asked patients about intolerance to chemicals, foods and drugs and found a normal bell-shaped curve of distribution: Most people in my medical practice have some degree of chemical intolerance, a small percentage are sensitive to just about anything that's synthetic and a small percentage report no sensitivity at all.
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Where a person sits on that curve may change, depending upon numerous factors, which include infection, toxic exposures, nutritional depletion, and life stress.
I contributed my findings on chemical sensitivity to one of the earliest textbooks dealing with the topic, which was edited by Mark Cullen of Yale University in 1987.
At the time I found that patients with multiple chemical sensitivities appeared to have difficulty digesting protein, a problem that can contribute to impairment of detoxification and disturbances of immune function. I still find that digestive disturbances play an important role in chemical intolerance, both as a cause and as a symptom.
I've suspected that my observations would apply to the general population, even though the patients I see are not typical of patients in a primary care practice; they're referred to me because they have chronic problems that have been resistant to conventional diagnosis or treatment.
Read: "Why You Need to Detoxify 24 Hours a Day."
Now, a new study from the University of Texas Health Science Center, San Antonio, confirms that chemical intolerance is common among primary care patients and is rarely diagnosed.
The researchers gave the Quick Environmental Exposure and Sensitivity Inventory (QEESI) to 400 adult patients in two primary care practices in San Antonio and found that 20.3 percent met the criteria for chemical intolerance. For three-quarters of them, there was no medical notation of any kind of hypersensitivity. Most of these patients were middle-aged working-class women.
The chemically intolerant patients were more likely to have poorer functional status, to limit social activities and to use more medical services when compared with non-chemically intolerant patients.
The researchers explain:
Patients who are chemically intolerant use health care services at increased rates (making an average of 23.3 visits to a medical professional per year). In addition, chemical intolerance is associated with poor quality of life and functional impairments leading to loss of employment and socioeconomic hardships.
Read: "Eat This, Detox That."
Symptoms of chemical tolerance may involve multiple body systems and can affecting thinking, moods, joints, muscles, the gastrointestinal tract, the heart and blood vessels, skin, and urinary system.
Patients with chemical intolerance often have concurrent diagnoses, which may include heart problems, bronchitis, asthma, sinusitis, hypothyroidism, autoimmune diseases, irritable bowel syndrome, migraine, fibromyalgia, and chronic fatigue syndrome.
The Texas researchers found that chemically intolerant patients tended to also be intolerant of medication, specific foods and alcohol and to have more severe symptoms than patients without chemical intolerance.
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An interesting finding was that compared to a healthy population from the same community, chemically intolerant patients scored lower for "masking factors." factors that might otherwise obscure awareness of an association between chemical exposures and symptoms. "In other words," the researchers state, "chemically intolerant patients may be more aware of their difficulties in tolerating everyday environmental exposures than are members of the healthy population."
This is important because most triggers for chemical intolerance, like solvents, pesticides, and volatile organic compounds, are inherently toxic, and according to the Texas researchers, have been "clearly linked with the development of chemical intolerance and associated neuropsychiatric symptoms, via a process referred to as toxicant-induced loss of tolerance."
Read: "Childhood Obesity Linked to Air Pollution"
In this sense, chemically intolerant people are like the "canary in the coal mine" and they carry a message for all of us.
British miners in the early 20th century would take a caged canary with them into the mines because the canary was more sensitive to toxic gas than the miners. If the canary passed out, it was time to leave the mine.
The same kinds of environmental chemicals that provoke symptoms in the chemically sensitive have been associated with serious health problems in people who do not consider themselves chemically sensitive.
An example of this can be seen in how rates of autism among children in the U.S. have increased dramatically over the past 30 years. Development of autism in children has been associated with prenatal and perinatal chemical exposures of the type that may provoke symptoms in people with chemical intolerance.
With so much of our time spent indoors, chemical exposures at home, the office, at school and in stores poses a substantial challenge. Learn more about this important health issue in Sick Building, Sick People.
Chemical intolerance should not be ignored or stigmatized. It should be seen as a common physiologic response to living in a chemical world.
Now I'd like to hear from you:
Have you been exposed to chemicals?
Have you noticed any immediate or long-term affects?
What steps have you taken to limit exposure and detoxify?
Has anything helped?
Please let me know your thoughts by posting a comment below.
Leo Galland, M.D.
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Leo Galland, MD is a board-certified internist, author and internationally recognized leader in integrated medicine. Dr. Galland is the founder of Pill Advised, a web application for learning about medications, supplements and food. Sign up for FREE to discover how your medications and vitamins interact. Watch his videos on YouTube and join the Pill Advised Facebook page.
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References and Further Reading
 Leo Galland, "Biochemical Abnormalities in Patients with Multiple Chemical Sensitivities, in Workers with Multiple Chemical Sensitivities", M. Cullen ed., Occupational Medicine: State of the Art Reviews. Hanley and Belfus, Philadelphia (1987), pp. 713-720.
 David A. Katerndahl, Iris R. Bell, Raymond F. Palmer, and Claudia S. Miller, "Chemical Intolerance in Primary Care Settings: Prevalence, Comorbidity, and Outcomes", Ann Fam Med July/August 2012 vol. 10 no. 4 357-365
Landrigan PJ. "What causes autism? Exploring the environmental contribution". Curr Opin Pediatr. 2010 Apr;22(2):219-25.
Larsson M, Weiss B, Janson S, Sundell J, Bornehag CG. "Associations between indoor environmental factors and parental-reported autistic spectrum disorders in children 6-8 years of age." Neurotoxicology. 2009 Sep;30(5):822-31. Epub 2009 Feb 10
Edelson SB, Cantor DS. "Autism: xenobiotic influences." Toxicol Ind Health. 1998 Jul-Aug;14(4):553-63.
Windham GC, Zhang L, Gunier R, Croen LA, Grether JK. "Autism spectrum disorders in relation to distribution of hazardous air pollutants in the san francisco bay area." Environ Health Perspect. 2006 Sep;114(9):1438-44.
Power Healing: Use the New Integrated Medicine to Cure Yourself. Leo Galland M.D., 384 pages, Random House
The Fat Resistance Diet Leo Galland, M.D. Broadway Books
Superimmunity for Kids : What to Feed Your Children to Keep Them Healthy Now, and Prevent Disease in Their Future, Leo Galland M.D. with Dian Dincin Buchman, Dell
This information is provided for general educational purposes only and is not intended to constitute (i) medical advice or counseling, (ii) the practice of medicine or the provision of health care diagnosis or treatment, (iii) or the creation of a physician--patient relationship. If you have or suspect that you have a medical problem, contact your doctor promptly.
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