I recently came upon a study on Google Scholar looking at the validity of using an application of your phone to identify foods and behaviors that trigger gastrointestinal symptoms in people.  If you want full access to the study, check it out here.

The app, called my Symptoms, seemed to be able to identify foods that trigger gastrointestinal symptoms such as gas, bloating, nausea, psychological symptoms, belching, discomfort, and diarrhea.  It also seemed to identify a relationship between psychological symptoms and GI symptoms.

There were other interesting findings as well.  First, they couldn’t find a relationship between non-GI symptoms such as headache and fatigue and food.  Instead, these symptoms were more correlated with psychological distress, indicating that daily stress and/or the psychological response to GI symptoms themselves may be what caused the headache or fatigue.

Second, they found that people with abdominal pain, gas and bloating could be stratified in to 3 separate patterns.  The first group was the most common, roughly 50% of the participants fell within it, and they saw a gradual rise in symptoms throughout the day.  The second group experienced symptoms between 3-4am and contained roughly 25% of the participants.  Finally, the third group experienced symptoms between 9-10am and contained the remainder of participants.

The final finding is something that doesn’t shock me in that it elicits GI symptoms, but by the sheer number of people who did it.  The average individual in this study still consumed calories after midnight on most days.  People who did this were more likely to follow the late night symptom pattern with symptoms occurring at 3-4am.

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Eating late at night: bad on at least 2 levels

Why would eating late in to the night cause an increase in symptoms such as gas, bloating, and abdominal pain?  Well, there are a couple of big reasons.  First, if you’re eating at midnight, you’re probably not sleeping either.  We get most of our deep sleep early in the night no matter what time we go to bed, so we have less opportunity to get deep sleep when we go to bed at 12am than if we go to bed to 10pm.

Secondly, our digestive enzymes and nutrient transporters in the gut follow a circadian rhythm.  Specifically, disaccharidases, enzymes that break apart 2-sugar molecules in to simple sugars, are highest during the day and lowest at night.  Then, the transporters that carry these simple sugars from the gut to the blood also follow this same rhythm.  So, what we get is poorly digested and absorbed carbohydrate sitting in the gut for longer periods of time when we consume high levels late at night.

Certain amino acids follow this same rhythm too, and one of particular interest to people with gut problems is histidine.  Theoretically speaking, histidine consumed late at night may sit in the gut for long enough for bacteria to convert it to histamine, contributing to histamine intolerance.

Finally, people who experienced the late night symptom pattern also tended to consume more alcohol.  Given how alcohol affects sleep, and often affects food timing and choices, it’s likely that people with late night symptoms are probably doing a number of these things.

Conclusion

This study is great for 2 reasons.  First, it identifies variations in symptom timing as well as food-symptom interactions.  More importantly, it validates the use of an electronic food/symptom diary to pinpoint foods that produce gastrointestinal symptoms.  The app, mySymptoms, is a step closer to personalized healthcare that I hope will help people identify specific foods that induce symptoms, rather than eliminate entire categories of foods.

In its current version, mySymptoms can do a better job at identifying relationships between foods and symptoms in people with GI problems.  We’re not that great in finding the causal foods because most of us look for things immediately prior to symptoms, something I covered in a blog you can find here.  The app mySymptoms can identify symptom patterns further out provided you have more than 28 days of data.

I spoke with the developer and they have some pretty good plans for the future.  The potential of this is pretty endless, as I believe that there are way more factors than specific foods that elicit symptoms, and when we can identify behavior/food interactions, that may be more important than just specific foods on their own.  With that data, you can just be more mindful of when you consume certain foods, rather than eliminate them altogether.

Hey folks, interested in mySymptoms?  You can find it on IOS and Android for $3 which seems pretty cheap to me.  It costs $2 to buy an app to make your Iphone fart, what’s an extra $1 to make sure you’re not farting all day everyday?

Have some questions for the developer?  I hope to put together an interview with him in the near future and would love to know what you want to know.  Just post your questions in the comments section below and I’ll pick some out to ask him.