The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 68

82. Why do mast cell patients react to leftover food?

  • Reacting to leftovers is arguably the strangest thing about mast cell disease. Lots of people tolerate foods that are freshly cooked but react to eating leftovers in the following days.
  • There are multiple ways that food can be broken down but I’m going to focus on how microbes do this, contributing to mast cell symptoms.
  • Microbes start breaking down food basically immediately. Any kind of food.
  • Freezing arrests microbial growth but doesn’t kill the microbes. Refrigeration slows down microbial growth but it doesn’t fully stop it. Cooking at high temperatures kills microbes.
  • Microbes break down food in several ways but the most important ones for this conversation are protein degradation and lipid (fat) degradation.
  • Proteins are composed of building blocks called amino acids. They are essentially long chains of amino acids. One of those building blocks is called histidine. When histidine is broken down, it produces histamine. This will happen when any protein is broken down, animal or plant.
  • However, animal meat contains hemoglobin, a very large protein that contains tons of histidine. Plants do not have this. This is thought to be one of the reasons why patients often do worse with meat leftovers than plant or grain based leftovers. Another reason is that some meats naturally have a high concentration of histamine to start with.
  • Lipids are found in both plants and animals but they are fundamentally different. Lipids in plants are usually oils while lipids in meats are fats. Lipids can be broken down by microbes or just by exposure to oxygen. This is what causes things to go rancid, more common in animal fats than in plant lipids. Acids and alcohols can be produced when lipids are broken down. Alcohols in particular can be triggering to mast cells.