What are FODMAPs and how do I follow a low FODMAP diet?
FODMAPs or Fermentable Oligo-Di-Monosaccharides and Polyols are a specific type of carbohydrate found in certain foods that you must avoid if you are following a low FODMAP diet. The family of FODMAPs include:
- Lactose from dairy products.
- Fructans: garlic, onions, wheat etc.
- Galactans: legumes such as lentils, beans, soybeans etc.
- Fructose: honey, certain fruits, high fructose corn syrup etc.
- Polyols: stone fruits such as avocados, peaches, plums, cherries, apricots, nectarines etc. and sweeteners such as xylitol, sorbitol, mannitol.
Why should you follow a low FODMAP diet?
FODMAPs create a few problems for your intestines that lead to Irritable Bowel Syndrome (IBS) and digestive system problems. The following symptoms can be caused by FODMAPs:
- Abdominal pain & discomfort
- Abdominal cramps
- Weight gain with difficulty losing weight
- Feeling like you don’t completely empty your bowel when you have a movement
- Alternating constipation and diarrhea
- Inconsistently formed stools such as random changes in size, shape and color
- Passing mucus
- Sometimes feeling hungry shortly after meals
- Fatigue after meals
- Brain fog
How does this happen?
FODMAPs draw a lot of water into your intestine which contributes to some of the symptoms listed above. Additionally, FODMAPs are not digested well and poorly absorbed which results in fermentation of the food that you eat. When your food ferments in the intestine, it causes the above symptoms as well.
Why can’t you digest them well?
If you have taken a lot of antibiotics throughout your life then you may have too many bacteria in your small intestine or abnormal bacterial colonies in your large intestine. Normally, the large intestine has a lot more bacteria than the small intestine; but if this shifts due to antibiotics and poor diet then you won’t be able to tolerate FODMAPs very well. If there is bacterial overgrowth in your small intestine known as SIBO (small intestinal bacterial overgrowth), then there will be rapid digestion and fermentation of the food you eat which leads to your digestive system problems. This can be compounded by yeast overgrowth and/or intestinal parasites.
Beans are a classic example of a FODMAP that has had many jokes made about their connection with gas. The gas produced by beans is a result of their fermentation in the bowels due to problems with gut bacteria. Not everyone gets gas from beans which means they are a great indicator of healthy gut bacteria.
How long should you follow the low FODMAP diet?
This depends on your current situation and what your doctor prescribes. Most individuals stay on it for approximately 2-6 weeks and then begin restoring healthy gut bacteria with specific prebiotic and probiotic-rich foods. The great thing about the low FODMAP diet is that you don’t need to be on it for very long to restore healthy digestive system function.
Your doctor may prescribe an antibiotic or herbal medicines to suppress the growth of bacteria in the small intestine during this diet. If your stool analysis shows yeast overgrowth or parasites then this diet will be extremely helpful for that as well. The healthier your gut bacteria, the better you will be at fighting infections in the intestine.
Can I combine the ketogenic diet with the Low FODMAP Diet?
Yes. All you have to do is follow the ketogenic diet and eliminate any FODMAPs that are listed on the ketogenic diet. The purpose of combining the two would be to burn more fat, reduce inflammation and to reverse insulin resistance.
How do I get started?
Simply start eating low FODMAP foods and small amounts of moderate FODMAPs. I have found a number of excellent resources for you to help with your low FODMAP diet.
You can download this free handout provided by Stanford University which should get you started right away.
Kate Scarlata, a registered dietician, has some excellent resources to help you including a shopping list, recipes and more on her website.
All of this material was founded by the Monash University Department of Gastroenterology where the research was done on FODMAPs. They are an excellent resource for FODMAP information and they even offer a mobile app to help you with a low FODMAP diet.
Remember to always consult with your doctor, nutritionist or registered dietician before trying the low FODMAP diet. If you aren’t getting the results you expect on a low FODMAP diet, then there may be other factors involved such as an intestinal parasite or yeast overgrowth that is holding you back. Be sure to be evaluated by a functional medicine practitioner to find the underlying causes of what may be impairing your progress.