Do mast cells make you gain weight and have a huge stomach when you are eating almost nothing?

I have seen MCAS drive weight gain in some patients, weight loss in other patients, and alternating weight gain and weight loss in yet other patients. Except for weight changes due to gain or loss of edema (swelling), we do not yet understand the molecular mechanisms underlying any of these frustrating phenomena. It should be noted, too, that many MCAS patients also suffer problems with (often acute) “bloating” of the abdomen, independent of any issues with actual obesity, and we don’t even yet understand the mechanism of this bloating in these patients.


Why does my suspected MCAS make it difficult for me to eat healthy foods like fruits and veggies? I can only eat 6 foods and sometimes I go for weeks at a time not being able to eat.

If your MCAS is only suspected, then it’s possible that MCAS or a large number of other diseases might cause difficulty with eating. Accurate diagnosis is the beginning of the road to effective therapy. We do not yet understand why some MCAS patients react to certain foods while other patients tolerate those foods but react to other foods. We also do not understand why some MCAS patients react to certain foods *sometimes* but then tolerate those same foods (or at least what appear to be the same foods) at other times.


My cholesterol is in the 500’s! Mast cell related? Salt wasting syndrome related?

I have seen many MCAS patients with high cholesterol levels and/or high triglyceride levels. In some of them, these high levels seem to come down a good bit upon “settling down” their mast cell disease. However, we still do not understand the molecular mechanisms by which the dysfunctional mast cells in such patients are driving, or at least contributing to, the elevated lipid levels. In my experience, salt-wasting syndrome in MCAS seems a bit less common than high lipid levels in MCAS, but there are no studies yet to put numbers on this, and there certainly is no understanding yet of the molecular mechanisms by which dysfunctional mast cells might drive salt-wasting.


Can I reintroduce foods after being free of major reactions etc. for a long period of time (while staying on my meds of course)! I miss having raw fresh fruits and vegetables.

As noted in earlier answers, as they gain better control over the disease, some MCAS patients can regain tolerance for previously intolerable substances. If the disease has been better controlled for some time, there’s nothing wrong with (cautiously) re-trying substances which previously were intolerable, with the obvious caveat that if a substance previously caused acute anaphylaxis, then it would probably be best to re-try that substance under very close supervision, such as being watched at the allergists office while trying the suspect substance.


What is recommended to do for MCAS patients who are experiencing gut pain?

The best approach to dealing with any medical problem is to identify the most accurate diagnosis. Whether the issue is gut pain or any other symptom, patients with mast cell disease should never assume any new symptom, or any major exacerbation of an old symptom, is necessarily due to their mast cell disease. Go get the new problem appropriately evaluated, in a timely fashion, and if some other diagnosis is identified as likely the cause of the problem, then — *regardless* of whether that diagnosis is *ultimately* attributable to the mast cell disease — it’s the standard treatments for the identified diagnosis which must be tried first. Only if no other diagnosis can be identified, or if standard treatments for some other identified diagnosis prove unhelpful, does it then become reasonable to consider mast-cell-targeted treatments in a patient with known mast cell activation disease. For abdominal discomfort, some of the medications which can sometimes be helpful include antihistamines, cromolyn, ketotifen, montelukast, vitamin C, diamine oxidase, proton pump inhibitors, laxatives, stool softeners, and others. It is not presently possible to predict which medications will be most likely to help which symptoms in which mast cell patients.


Is there a way to reintroduce foods that you have become anaphylactic to?

I have seen some mast cell patients regain tolerance for previously intolerable substances as they gain better control over their mast cell disease. For some patients, desensitization therapy (usually managed by an allergist) can help regain tolerance.

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If you would like to see a NY Mast Cell Activation Disorder specialist, Dr. Lawrence Afrin is now seeing patients in a private practice setting at our office in Armonk, NY. To make an appointment with Dr. Afrin, please call the office or contact us here