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What can corn tell you about your digestion?

Ever thought about how long it takes for food to go from one end to the other end and what that might be telling you about your digestion?

Those of you with children are perhaps a little more in tuned into how what your children are eating is affecting their poop and may have become accustomed to seeing sweetcorn in their poop or noticing reddish coloured poop after eating fresh beetroot. More on sweetcorn further below. Gut transit time (GTT) is the time it takes for ingested food to travel through the gut. It varies from person to person, and also from day to day, for different reasons. Some of you have noticed that when travelling, especially when crossing many time-zones, that for the first few days at your new destination you are not as regular as normal.

A normal GTT of around 16-36 hours is a key determinant of a well functioning digestive system. Food has to travel through 7-8 meters of intestine, from the time it enters your mouth. The longer it takes for food to move through your gut, the greater the opportunity for the production of harmful bacterial degradation products. These by-products when produced in large amounts generally doesn’t make us feel very well and is not a good thing. A sluggish gut or slow transit is associated with constipation and bloating, but to be clear not everyone who suffers with constipation has a slow transit. And interestingly, regular daily bowel movements doesn’t guarantee a normal GTT.

So, whether you are regular or not so regular, it’s worth checking in on your GTT and taking the corn test. As we aren’t able to digest the outer husk of the corn kernel, corn in the form of corn kernels or corn on the cob gives us good insight into GTT.

How to do the corn test:

  1. Wait three days (or even up to 7 days if you suspect you have a sluggish gut) from the last time your had corn.
  2. Then have a healthy serving of corn kernels (3 tablespoons or so) or a corn on the cob, and notice how long it takes for you to spot the corn in your poop. If your GTT is a little slow, taking simple steps such as increasing your fibre and fluid intake, and doing daily exercise, can help to speed things up. In the next post we will look at some causes of a slow GTT.