What is the prevalence of Multiple Chemical Sensitivity?

It has been noted that more women develop MCS than men. It is hard to know how many sufferers there are because most people are misdiagnosed but an estimated one third of the population has the genetic structure to be susceptible to the disease.

Its difficult to get current studies. There's no money in it. However a 1997 survey of geriatric veteren self reported chemical sensitivities at the rate of 37%, Bell, Walsh, Gross,net al.

MCS affects as many as 30% of the population with notices symptoms.

Over the "civilised" world it's around a third of the population. More women seem to be affected.

It seems to be worse for people who have had exposure to heavy chemicals or exhaust. Perhaps it is worse for those with fair complexion, redheads. I am not entirely sure.

Chemical sensitivity is a medical condition characterized by adverse health effects from exposure to common chemical pollutants and products. This study investigated the prevalence of chemical sensitivity in four countries—the United States (US), Australia (AU), Sweden (SE), and the United Kingdom (UK). In addition, it investigated the co-prevalence of chemical sensitivity with medically diagnosed multiple chemical sensitivities (MCS), fragrance sensitivity (health problems from fragranced products), asthma/asthma-like conditions, and autism/autism spectrum disorders (ASDs). Using nationally representative population samples in each country, data were collected in June 2016 and June 2017 through on-line cross-sectional surveys of adults (n = 4435). Results found that, across the four countries, 19.9% of the population report chemical sensitivity, 7.4% report medically diagnosed MCS, 21.2% report either or both, and 32.2% report fragrance sensitivity. In addition, 26.0% of the population report asthma/asthma-like conditions, of which 42.6% report chemical sensitivity and 57.8% fragrance sensitivity. Also, 4.5% of the population report autism/ASDs, of which 60.6% report chemical sensitivity and 75.8% fragrance sensitivity. Among individuals with chemical sensitivity, 55.4% also report asthma/asthma-like conditions, 13.5% autism/ASDs, and 82.0% fragrance sensitivity. Although the prevalence of chemical sensitivity across the countries is statistically different, its co-prevalences with other conditions are statistically similar. Results also found that, for 44.1% of individuals with chemical sensitivity, the severity of health effects from fragranced products can be potentially disabling. Further, 28.6% of those with chemical sensitivity have lost workdays or a job, in the past year, due to exposure to fragranced products in the workplace. Results indicate that chemical sensitivity is widespread across the four countries, affecting over 61 million people, that vulnerable individuals such as those with asthma and autism are especially affected, and that fragranced consumer products can contribute to the adverse health, economic, and societal effects.

Ive called the CDC for this and it is unclear if they know but wont share, or don't keep track. There are references from a tiny percent to a third fo the population reacting to triggers, but of course, to what extent are they disabling reactions.

Approximately 1/4 of the population in the USA have some sensitivity . Over 10% of the population have sufficient severity to receive a clinical diagnosis.

In my case stay away from humans and the chemicals they wear and use daily.

More people have chemical sensitivity and don't know that they have that. There have been over exposures noted from military and from industrial factories where people have been Overexposed and have MCS because of it yet they don't know that they have MCS

4% are likely to have a diagnosable condition of MCS.
34.7% of people are sensitive to fragrance and experience negative health effects from exposure to it.

More women than men, but men do get it too.
Men, however, may be underreporting it because of the social stigma and the toxic masculinity that surrounds men's pain.

Babies understood and accepted to be chemically sensitive generally, but would not carry a diagnosis of MCS because their immune system strengthens as they age.

https://link.springer.com/article/10.1007/s11869-019-00672-1

It tends to affect women a lot more than men...about a 75/25 split, and sadly, yes we are seeing more and more children affected.

Approximately 27% or 55 million adults worlwide

12% to 15% of the population are estimated to have MCS and numbers are increasing due to increases of toxic chemicals being produced and used in the environment. Men and women can be affected. Adults are more commonly affected due to the body's toxic load increasing over time.