IBS & FODMAPS: Understanding Carbohydrates and Digestive Health

Here’s the deal. Whether you have Irritable Bowel Syndrome, or not, must of us do not understand what carbohydrates do for and in our bodies. A confusing requisite to dietary health, carbohydrates fuel our cells and muscles into action, and supply energy to our brains for mental acuity. But how carbohydrates breakdown in our body can make the difference between indigestion and a calm, satiated digestive system.

There are a few steps involved in breaking down carbs from a whole food to its simplest, chemical form — before it is absorbed and used up by our powerhouse organelle, mitochondria.

What you need to know?

  • Carbohydrates become simple-sugar molecules when digested.
  • Digestion of carbohydrates starts in the mouth with mastication and the release of amylase–an enzyme that breaks down carbohydrates.
  • Besides a bit of churning, carbs do not breakdown in the stomach. Digestion of fats and protein predominantly occur in the stomach from churning and protein specific enzymes.
  • Carbohydrates are fully broken down in the small intestine before moving to the large intestine.
  • FINALLY, food in our stomach passes through a valve, called the duodenum, into the small intestine. At this point the pancreas releases enzymes to aid in the digestive process. Like a Russian nesting doll, the chemical chains of carbohydrates, going through your digestive system, slowly get smaller and smaller until you have the smallest doll possible–a single molecule form of what was once a whole piece of food.
     This is some neat stuff. 


IBS and Carbohydrates

Did you know, Canada has some of the highest rates of IBS in the world? There is an estimated 5 million people currently suffering with symptoms of IBS.1

With IBS new research is finding that some of these carbohydrates are not absorbed at a time when they should. As a result they end up having an osmotic effect; meaning, excess water is pulled into the intestine causing excess fermentation. Fermentation of these carbohydrates is the proposed issue for people experiencing IBS.

Some people experience diarrhea, constipation, gas and intestinal pain from trapped gas. Overall, is it due to inadequate enzyme release? Is it due to food sensitivities? Poor microflora?  We really don’t know for certain, but some people experience relief by eliminating certain carbohydrates with the Low FODMAPS diet. In fact, an Australian study found that an impressive number of 75% of people in their study experienced relief  from following a low-FODMAP diet.2


That’s a high percentage of improvement for a study looking at diet.


What you need to know about the low-FODMAP Diet?

  • Understanding FODMAPs means understanding how short-chain sugars breakdown in the body and why we believe certain types of carbs are correlated with symptoms of IBS. 
  • FODMAPs is an acronym for a variety of short-chain sugars from carbohydrates.  
  • Imagine a short metal chain, each link is carbohydrate. When broken down through digestion the chain links will no longer be connected, leaving you with individual, unlinked metal rings.  Consider each link a molecule. 
  • FODMAPs stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polysaccharide Sugars.  


The FODMAPs diet (Fructo, Oligo, Di, Mono, and Polysaccharide Diet) is a helpful way to knowingly avoid eating certain high starch, sugar, and other problem carbohydrates


If you suffer from digestive health issues, like I do, there is a lot to learn about the FODMAPs diet. To ease yourself into understanding healthful and potential problem foods, here is a list of FODMAP friendly foods to get you started.

Every body is different when it comes to diet and how you may feel after eating certain foods. For example, legumes  are on the High FODMAP Foods list found below, but you personally may not experience digestive issues after eating legumes. Someone else, however, may have to completely avoid eating legumes. Everyone will have different “trigger” foods.  

In stating that reality, there is a unanimous observation among individuals experienceing IBS and IBD symptoms that a diet lower in sugar, lactose, starch, alcohol, and high-fat proteins is beneficial. The best way to successfully implement these helpful tools is by choosing whole foods over processed foods, and choosing foods from the Low FODMAP foods list.


Food Category High FODMAP Foods Low FODMAP Food
Vegetables Asparagus, artichokes, onions(all), leek bulb, garlic, legumes/pulses, sugar snap peas, onion and garlic salts, beetroot, Savoy cabbage, celery, sweet corn Alfalfa, bean sprouts, green beans, bok choy, capsicum (bell pepper), carrot, chives, fresh herbs, choy sum, cucumber, lettuce, tomato, zucchini.
Fruits Apples, pears, mango, nashi pears, watermelon, nectarines, peaches, plums Banana, orange, mandarin, grapes, melon
Milk and dairy Cow’s milk, yoghurt, soft cheese, cream, custard, ice cream Lactose-free milk, lactose-free yoghurts, hard cheese
Protein sources Legumes/pulses Meats, fish, chicken, Tofu, tempeh
Breads and cereal Rye, wheat-containing breads, wheat-based cereals with dried fruit, wheat pasta Gluten-free bread and sourdough spelt bread, rice bubbles, oats, gluten-free pasta, rice, quinoa
Biscuits (cookies) and snacks Rye crackers, wheat-based biscuits Gluten-free biscuits, rice cakes, corn thins
Nuts and seeds Cashews, pistachios Almonds (<10 nuts), pumpkin seeds

Click here for more info on understanding FODMAPs. If you have any questions regarding carbohydrates and digestive health, sign-up to follow my blog, or email me at hello@healthyrootsmeg. Curious about the Lemon Energy Bites seen in the article photo, click here.

1(2016)Irritable Bowel Syndrome (IBS). Canadian Digestive Health Foundation, www.cdhf.ca

2Gibson, P. R.,& Shepherd, S. J. (2010) Evidence-based dietary management of functional gastrointestinal symptoms: The FODMAP Approach. Journal of Gastroenterology and Hepatology, 25, 252-258.

3(2016)The Monash University Low FODMAP Diet: examples of low and high FODMAP foods. Monash University: medicine, nursing and health sciences.www.med.monash.edu