Identifying triggers

While there are some common triggers, most people affected by MCAS struggle to identify all the triggers responsible for their symptoms. And each individual has a unique set of triggers that cause their mast cells to overreact.

While avoiding or reducing exposure to triggers can improve symptoms, most people with MCAS will experience multiple triggers. This can make it difficult to work out what is causing a reaction. 

Identifying individual triggers is best done by keeping a diary which includes foods, exposure to chemicals and fragrances, stress, change in temperature and exercise. This helps us to identify any patterns or common themes which can help us to understand more about what is triggering our reactions.

It is important to remember that food and environmental triggers can change over time and that no single approach works for everyone. Restarting the diary if problems arise in the future could help to identify new or changing triggers.

Share your triggers and symptoms with friends and family so they can help with management and reducing exposure to triggers. You can download our PDF about triggers here. We hope this will help you to talk to others about the triggers you are trying to avoid.

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The Histamine Bucket Theory

This histamine bucket theory is a useful visual aid to help us to understand the impact of factors which contribute to histamine levels. This theory can help us to understand the impact of different activities and situations on histamine levels and therefore, how to reduce this exposure where possible.

You could think of your body as an empty bucket. Different foods and activities fill your histamine bucket at different speeds but combine to form the total level of histamine in your body.

If you can keep your bucket at a lower level, you may feel better because a fuller bucket could mean you have more symptoms. Managing triggers, reducing exposure to known triggers, and taking medication could all help to manage the level of your bucket.

You can download a PDF of this theory to share to help others understand.

Specialist diets

Many people affected by MCAS find that foods are common triggers. Although sometimes it is obvious which food is triggering symptoms, this isn't always the case. Where we suspect food is the culprit, it can be difficult to identify food triggers as we usually consume multiple foods at the same time. Reactions are not always instant and can sometimes take several days to trigger symptoms. Therefore, a systematic approach is needed to reveal which foods or food groups are causing symtoms.

Some specialist diets can be helpful. Dietary management strategies most frequently used by people with MCAS are:

  • Low histamine
  • Dairy free
  • Gluten free
  • Low Salicylates
  • Low oxalates
  • Low FODMAP
  • Low sugar (Ketogenic)

Or a combination of any of the above.

Elimination diets ​should only be implemented under the guidance of a healthcare professional. The food group should be removed for a period of 6 weeks and then foods reintroduced one by one to see if there is a reaction to an individual food.

A Healthcare professional must be involved with any restriction diets for children.

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