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FODMAP Diet: Oligosaccharides, Monosaccharides, and Polyols

Continuing on with the FODMAP Diet from the last post. Will use this post to finish the diet explanation, and then post later to talk about where I’m at with it.

People have asked what FODMAP means. It stands for ‘Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols’. As acronyms go, it’s not the most helpful. The breakdown into what each item means helped me a lot more. It is a complicated diet change and needs to be studied before attempting and reviewed all the way along. A registered dietician is super helpful.

We talked about lactose, which is the only disaccharide that can cause issues, so that’s the ‘D’ in FODMAP. Fructans are one of the two oligosaccharides we need to worry about; the other being…

Galacto-oligosaccharides (GOS)
Galactose sugars joined together with a glucose and fructose molecule at the end. Nobody can digest or absorb these at all, so they are big IBS triggers. Some people have different levels of tolerance – your mileage may vary.

Avoiding them is pretty easy though. Just skip all beans, chickpeas and lentils. Wait, your diet consists of a lot of those? You have my sympathies.

And when they say beans, they mean all true beans. Kidney, baked, black, cannellini, great northern, pinto, navy, lima, butter beans, adzuki, soy, mung and fava. (Sorry Hannibal.) Green beans are fine.

Soy gets tricky.

  • Soybeans in any whole form are out.
  • Soy milk is okay, as long as it’s from a soybean extract and not made from whole soybeans.
  • Soy-based yogurt can be okay in small amounts. Same with soy cheese.
  • Soy flours (as well as chickpea, lentil and pea flours) are generally okay if only small amounts in a recipe. Assess your own tolerance.
  • Soy sauce is fine, unless you have gluten issues in which you can get the gluten-free version called Tamari.
  • Tofu, tempeh and miso are usually okay because of how they have been processed.

Make sense?

This part hasn’t been a big issue for me. Beans and the like aren’t a big part of our diet. I do miss hummus, and Mucho Burrito is right out. Big problem here though is that removing these foods can cut out a huge source of the soluble fibre you DO need. I’m taking Metamucil to counter that (psyllium is one of the fibers that don’t cause too many issues, but chia seeds work well too).

Like Lactose and Disaccharides, Fructose is the only Monosaccharide we need to worry about. Fructose, also known as the ‘fruit sugar’, is in every fruit as well as honey and the much feared HIGH-FRUCTOSE CORN SYRUP. Some grains and veggies have it too.

But you don’t have to dump all fruit. While fructose can be poorly absorbed, when it is digested with equal or greater amounts of glucose, the glucose ‘piggybacks’ the fructose through the bowel lining. You can still overwhelm this by eating too much fructose at one time though, so space out your fruit intake. No more than the equivalent of one average orange at a time. A banana, small melon slice, half cup of pure juice, etc.

I’m also just reading that they suggest no more than three tablespoons of tomato paste at a sitting. Which means my wife’s awesome low-FODMAP spaghetti sauce isn’t safe after all. Oops.

Foods that have more fructose than glucose are out: apples, pears, mangoes, asparagus, peas (yay!), agave nectar, HFCS, concentrated fruit juice, honey.

Most everything else is okay, as long as fruits and nuts are in reasonable quantities. Peanut butter and jam are in here as well in small amounts.

Sugar alcohols, often with names that end in ‘ol’ like sorbitol, mannitol, etc. Some fruits and veg and a bunch of artificial sweeteners have them. Sugar-free gums are typical culprits – again a mistake I made a few times.

Out: Apples, apricots, peaches, pears, watermelon, mushrooms (no!), cauliflower, peas (yay!). Gum, mints and candies with polyol artificial sweeteners.

In: Most everything else. A couple cherries, a quarter avocado, half cup of sweet potato and a single stalk of celery are okay but no more.

My reference to all this has been “The Complete Low-FODMAP Diet: A Revolutionary Plan for Managing IBS and Other Digestive Disorders” by Sue Shepherd and Peter Gibson. Shepherd was one of the scientist who has been working on this subject for a long time, so I figured why not go with the source. I also have the cookbook from the same source – awesome super-tasty recipes.