FODMAPs are a large group of dietary sugars (carbohydrates) found in many common foods such as specific dairy products, wheat and other grains, and fruits and vegetables. FODMAPs is an acronym, which stands for:
Polyols (sugar alcohols e.g. artificial sweetener)
The key FODMAPs are:
- Oligosaccharides, such as fructans/fructo-oligosaccharides (found in grains and vegetables) and galactans/galacto-oligosaccharides (found in legumes)
- Disaccharides – such as lactose (found in milk)
- Monosaccharides – such as fructose (found in fruit)
- Polyols – sugar alcohols e.g. artificial sweeteners such as sorbitol, mannitol, xylitol
FODMAPs are generally poorly absorbed in all people, however, those with specific gut disorders such as irritable bowel syndrome (IBS) are thought to experience the uncomfortable symptoms due to the gut being unusually sensitive. When these sugars are poorly absorbed in the small intestine, they continue into the large intestine, where they act as a food source to the bacteria that live there. The bacteria then ferment the undigested FODMAPs to produce gas and cause the symptoms associated with IBS such as lower abdominal discomfort/pain, bloating, distention, nausea, excessive wind (flatulence), altered bowel habits (diarrhoea and/or constipation). Each person’s symptoms are individual, depending on the severity of the reaction to a FODMAP. The length of time a symptom lasts also differs between individuals, depending on the amount of FODMAPs in the diet, a person’s reaction to them, and the severity of these reactions.
Hydrogen/methane breath-testing can be used to assess if a person absorbs fructose, lactose and sorbitol effectively. It is not essential but it may be helpful in tailoring the Low FODMAP Diet.
A Low FODMAP Diet (i.e. a diet that limits, but does not eliminate FODMAPs) is usually recommended for 6-8 weeks at a time to assess your tolerance. Progress should be assessed by an accredited dietitian who can help advise which foods can be gradually re-introduced into your specific diet. The goal is to identify the threshold at which you are able to consume FODMAP containing foods without causing bothersome gastrointestinal symptoms.
It is not generally recommended that you follow a low FODMAP diet for life; restricting dietary intake of a wide array of foods should generally be avoided if possible to reduce the risk of nutrient deficiencies. FODMAPs are a normal part of the diet and have benefits for health, such as providing fibre and prebiotics for gastrointestinal health. That is why, if you choose to follow such a diet, it should be done under supervision of a dietitian.
A few examples of food sources high in each of the FODMAPs are listed below. The list is not complete, and is subject to change as new data becomes available regarding the FODMAP content of foods.
• Fruits: apples, boysenberries, cherries (>3), figs, pears, nashi pears, peaches, mango, watermelon, tamarillo, tinned fruit, dried fruit, large serves of fruit
• Vegetables: asparagus, artichokes, sugar snap peas
• Sweeteners: honey, fructose (>5g daily*), high fructose corn syrup
• Drinks: fruit juice, soft drinks sweetened with fructose, sparkling wine, dessert wine, ciders, rum
• Fruits: custard apples, nectarines, peaches, persimmon, rambutan, tamarillo, watermelon
• Vegetables: artichokes, asparagus (>3), beetroot (>4 slices), Brussel sprouts (>½ cup), broccoli (>½ cup), cabbage – savoy (>1 cup), chicory root, corn (>½ cob), fennel (>½ cup), garlic, leeks, okra, onions, peas (>1/3 cup), radicchio lettuce, snow peas (>10), spring onion (white part)
• Cereals: wheat, rye, barley products (bread, pasta, couscous, crackers, biscuits)
• Nuts: cashews, pistachios
• Legumes: all (chickpeas, lentils, dried/canned beans, baked beans, soy beans)
• Drinks: soy milk
• Milk: cow, goat and sheep
• Cheese: fresh (cottage, ricotta, cream cheese, mascarpone)
• Other dairy products: yoghurt, ice cream, custard
• Fruits: apples, apricots, avocado (>¼), blackberries, cherries (>3), longan (>10), lychees (>5), nashi pears, nectarines, pears, peaches, plums, prunes, watermelon
• Vegetables: cauliflower, celery (>1 stick), mushrooms, snow peas, sweet potato (>½ cup)
• Sweeteners: sorbitol (420), mannitol (421), xylitol (967), maltitol (965), isomalt (953)
The low FODMAP diet is becoming more prominent since it has been widely researched and published in international medical journals and has now seen it accepted and recommend as one of the most effect dietary therapies for treating IBS. One in seven adults suffer from IBS or other functional gastrointestinal disorder (FGID). The underlying cause of IBS is not well understood and a number of factors may trigger symptoms, and since there is no “official” diagnosis (hence it being a syndrome), many people are turning to the Low FODMAP Diet for help.