Toxins are all around us. They are present in our homes, water, air, and soil.

Our exposure to toxins is greater now than at perhaps any other point in history. Modern life has brought a slew of chemicals that we ingest, inhale, inject, and even implant in ourselves.

As a result, rates of chemical intolerance are on the rise. In the last decade alone, there has been an estimated 300% increase in rates of chemical intolerance, with somewhere around 12-25% of the population affected.

While some individuals may never experience chemical intolerance, many others will develop symptomatic cases of what is known as Toxicant Induced Loss of Tolerance or TILT. This condition makes someone highly sensitive to toxins in their environment.

TILT presents as a diverse range of symptoms that cause illness, discomfort, and disability. In my practice, I see patients who have often struggled for years with a confounding mix of symptoms that elude easy diagnosis. Because toxins are so prevalent in our environments, pinpointing specific triggers can be challenging and, of course, very frustrating for patients who just want to feel better.

In addition, a growing body of evidence now links TILT with Mast Cell Activation Syndrome (MCAS). Together these two conditions explain many of the obscure symptoms patients are often told are “all in their head.”

I’m here to tell you that it is not all in your head. Chemical intolerance and MCAS are very real conditions that significantly impact your health and well-being. Helping my patients identify and eliminate toxic triggers in their environment is pivotal to laying the groundwork for healing.


Toxin Induced Loss of Tolerance (TILT)

Toxin induced loss of tolerance (TILT) and chemical intolerance (CI) are terms often used interchangeably. They both describe a category of disease marked by allergica-like responses to certain environmental toxins.

Unlike an allergy caused by an antibody-mediated response, TILT usually does not involve the classic IgE markers. It is a class of disease all itself and one we are discovering new information about every day.


Diagnosing TILT

TILT can affect any system in the body. While some individuals know the exact chemical exposure that led to the development of a new intolerance to an array of toxins, others struggle to connect the dots between symptoms. Doctors and patients alike can be frustrated by a puzzling mix of symptoms affecting multiple systems of the body.

As one researcher aptly described it: “Too many symptoms in too many organ systems.”

Thankfully, we have effective ways to identify those suffering from chemical intolerance. There are two prominent questionnaires available.


Brief Environmental Exposure and Sensitivity Inventory (BREESI).

This 3-question screening tool provides a quick way to assess the likelihood that someone has TILT. Its efficacy is well-validated. If someone responds yes to one or more questions on the BREESI, a deeper assessment is called for.


Quick Environmental Exposure and Sensitivity Inventory (QEESI)

The QEESI is an internationally validated 50-item questionnaire seen as the standard for assessing TILT. This is the tool I use with my patients as it provides an in-depth analysis of symptoms and triggers, which guides us in identifying areas in their environment that cause problems.

Acknowledging someone is dealing with chemical sensitivity is only the first step. Treatment requires identifying the toxins that initiate and trigger ongoing reactions. The QEESI provides the necessary information to begin the process.


What Causes TILT?

There are two distinct phases to the development of TILT: Initiation and triggering.

Initiation – The first stage of TILT occurs when someone who is already susceptible, usually due to an underlying genetic factor, is exposed to a toxin. The exposure could be a one-time high-level exposure, as we saw from the World Trade Center tragedy in 2001. First responders on the scene were exposed to an enormous load of toxin-filled dust. Many of them subsequently developed intolerance to everyday chemicals that previously were never a problem.

Initiation can also occur as a result of prolonged, low-level exposure to toxins. For example, individuals who have silicone breast implants may experience chronic low-level exposure to organosiloxanes leaching from the implant itself. Some women go on to develop adverse reactions to everyday chemicals, often followed by worsening of symptoms.

In the initiation phase of TILT, the initial exposure causes a bodily reaction that makes the individual more sensitive to their environment. While previously poorly understood, new research points to the mast cells’ role in the initiation response. We’ll look more closely at that in a moment.

Triggering – Due to the overreaction to the initiating event, an individual essentially becomes sensitized. Subsequent low-level exposure to the same toxin or even a completely different toxin can trigger a symptomatic response. At this point, the person may become aware of a new and worsening sensitivity to common household items.

Chemicals that may become triggers include:

  • Fragrances
  • Detergents
  • Hair spray
  • Deodorant
  • Cleaning chemicals
  • Carpet
  • Exhaust fumes
  • Cigarette smoke
  • Glue
  • Stain remover
  • And many more everyday items

For many people, this new sensitivity comes as an unpleasant surprise. Everyday activities like riding in an elevator can suddenly be problematic if, for example, a coworker wearing perfume is present. While in the past you may not have noticed, now, you develop a sudden headache and nausea for what seems like no good reason.

Symptoms of TILT range from mild to more disruptive:

  • Nausea
  • Headache or migraine
  • Brain fog
  • Difficulty with attention and memory
  • Fatigue
  • Muscle pain
  • Allergy-like symptoms
  • Mood changes


Mast Cells

So, where do mast cells come into play?

Your mast cells are specialized white blood cells that produce, store, and release signaling chemicals known as mediators. When mast cells detect a threat, they rapidly (think sub-second!) release mediators to alert other cells to respond.

They are like the ultimate environmental activist, jumping into action when they sense an environmental threat.

They are constantly on guard against any pathogen, toxin, or foreign invader you may come in contact with. The mediators they release are critical to your tissue’s ability to respond and repair after an insult.

Unfortunately, mast cells can make mistakes. If they become inappropriately activated, a condition known as mast cell activation syndrome (MCAS) can develop.

Someone with MCAS suffers from chronic inappropriate mast cell activation, where the cells regularly release mediators that are not needed. These mediators contribute to inflammation and a variety of symptoms that can affect multiple organ systems.

Because mast cells are present throughout the body, the exact symptoms a person with MCAS may experience vary. In addition, symptoms are often wide-ranging, affecting multiple body systems. If that sounds familiar, it’s because TILT acts in a very similar way. This similarity provides the key to unlocking effective treatment for both TILT and MCAS.


The Link Between TILT and MCAS

MCAS and TILT are often intertwined. We believe they are closely related because both conditions share similar symptoms and pathophysiology.

The often immediate reaction those with TILT experience when exposed to toxins points to the potential role mast cells play in their sensitivity. Out of all the cells in the immune system, mast cells respond quickest to a perceived threat. Their release of inflammatory and allergic-like mediators can be almost instantaneous, making mast cells a likely candidate to explain the mechanism behind TILT.

To test this theory, my practice recently participated in a study examining the link between TILT and MCAS. We compared QEESI scores among three groups:

  • Individuals diagnosed with MCAS
  • Individuals diagnosed with TILT/CI
  • Control group


Here are our results:

“More than half (59%) of the MCAS group met criteria for CI. A logistic regression model illustrates that as the likelihood of patients having MCAS increased, their likelihood of having CI/TILT similarly increased, to a near-perfect correspondence at the high ends of the QEESI and clinical MCAS scores. Symptom and intolerance patterns were nearly identical for the CI and MCAS groups.”

The evidence strongly suggests a direct link between toxic exposure, loss of tolerance, and resulting MCAS. It appears mast cells play a role initiating and triggering TILT. At the same time, once an individual develops TILT, I suspect their risk of MCAS increases. More research is needed in this area.


Successful Treatment

Once we arrive at a definitive diagnosis of TILT and/or MCAS, that is when the real work begins. We want to go beyond just treating the symptoms and instead create the conditions for real healing to take place.

The patients I see have often been searching for answers for a long time. It can be a huge relief to receive some clarity. From there, we work together to take the necessary steps towards recovery.


Step 1: Eliminate triggers

If a person continues to be exposed to toxic triggers, they will continue to struggle. It is not possible for the body to fully heal and repair until the specific toxic trigger is eliminated.

However, identifying which toxins are triggers can be very challenging. There are tools I use in my practice to guide the process of discovering which toxins are present in the home and in what situations a patient is experiencing a reaction. Sometimes a patient needs to eliminate a lot of products from their home environment and then trial how they respond as they slowly introduce a select few.

The same can be true for what a person eats. An elimination diet is often helpful in this stage, as many individuals with TILT and/or MCAS also have sensitivities to certain foods.

In my experience, people with TILT and MCAS are very attuned to how their body responds to toxins, and working together, we can successfully identify and remove the big triggers.


Step 2: Eliminate all toxins

Someone who has MCAS and/or TILT is highly susceptible to overreact to any toxic trigger. Part of the healing process is to remove as many toxins from the home environment as possible. This way, with the triggers removed, the work of regulating the body’s response can begin.

In part 1 of this series, I provide information on specific toxins and suggestions for removing them. This step is essential for all my patients. Think of it as reducing the toxic burden on your body.

The more toxins you are exposed to, the more work your body has to do to neutralize and remove them. I see many patients whose bodies are overworked and over-reacting, whether they have TILT, MCAS, Lyme disease, or something else. They are worn out and tired, and my goal is to help them return to a place of balance.

For that to happen, we must reduce the load their body is carrying, by reducing their toxic burden. While there may be some toxins that it is difficult if not impossible to avoid, there are many that can easily be removed by substituting a better product in its place.


Step 3: Treat the immune system

At the same time, as we remove toxins and triggers from a person’s environment, we also need to address what is happening in the immune system. A big part of what I see in my patients is an overactive immune response to the environment. Bringing the immune system into better regulation is key to successful treatment.

Repairing the immune system requires a multi-pronged approach that addresses the whole person. When dealing with a condition as complex as TILT and/or MCAS there is no magic pill that will fix everything. Working together, I help my patients choose a combination of treatments that holistically support healthy immune function. These may include:


Hope for TILT and MCAS

As our knowledge of the complex interactions between toxins in our environment, mast cells, and chemical intolerance increases, our hope for treatment and prevention grows. By eliminating toxins from our homes and larger environment, we protect ourselves from inappropriate mast cell activation and resulting intolerance.

The work of identifying and removing toxins from your home can feel daunting. I encourage everyone to take it one step at a time and to reach out for help if you’re experiencing troubling symptoms that can’t be explained. There is so much that can be done when you take a holistic approach to wellness that includes the environment in which you live.



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