Evidence-Based Dietary Management of Functional Gastrointestinal Symptoms

Efficacy of the Low FODMAP Diet

Efficacy of restricting dietary fructose and/or sorbitol has been reported in several observational studies^[35–38] and the benefits appeared to be durable.^[36] The nature of the diets used, however, was generally poorly defined. Using a well-defined diet, restriction of fructose and fructans, together with general avoidance of other FODMAPs led to impressive global symptoms response in three out of four patients with IBS and fructose malabsorption in a retrospective study.^[39] Efficacy was durable and was closely related to dietary compliance. That the efficacy of the low FODMAP diet was due to restriction of fructose and/or fructans in the diet was convincingly shown in a subsequent double-blinded randomized quadruple-arm placebo-controlled re-challenge trial.^[40] Further evaluation of the diet in other groups with functional gut symptoms has shown consistent benefit in patients with quiescent inflammatory bowel disease and ileal pouch. An evaluation of patients who did not have a breath hydrogen test supported the efficacy of the diet in those with complete fructose absorption.^[41] Of importance is that efficacy is not restricted to patients with diarrhea-predominant IBS, but applies equally to any bowel habit. Thus, the evidence base for efficacy of the diet is now substantial.

The ability of those instructed in the low FODMAP diet to adhere to it is remarkably good. More than 75% of patients were judged to be completely or mostly compliant with the diet in a retrospective review median 14 months (range 2–40 months) after implementation of the diet. In patients with inflammatory bowel disease, dietary compliance and efficacy of the diet were associated with more time availability, higher education status, and the use of specific cookbooks. These findings suggested that an understanding of the dietary principles and allocation of time to work on applying the diet were important to ensure success. These findings are not surprising.

Table 1. Food sources of FODMAPs (where FODMAPs are problematic based on standard serving size) and suitable alternatives
FODMAP	Excess fructose	Lactose	Oligosaccharides (fructans and/or galactans)	Polyols
Problem high FODMAP food source	Fruits: apples, pears, nashi pears, clingstone peaches, mango, sugar snap peas, watermelon, tinned fruit in natural juice Honey Sweeteners: fructose, high fructose corn syrup Large total fructose dose: concentrated fruit sources; large serves of fruit, dried fruit, fruit juice	Milk: cow, goat and sheep (regular & low-fat), Ice cream Yoghurt (regular & low-fat) Cheeses: soft & fresh (e.g. ricotta, cottage)	Vegetables: artichokes, asparagus, beetroot, Brussels sprout, broccoli, cabbage, fennel, garlic, leeks, okra, onions, peas, shallots. Cereals: wheat & rye when eaten in large amounts (e.g. bread, pasta, couscous, crackers, biscuits) Legumes: chickpeas, lentils, red kidney beans, baked beans Fruits: watermelon, custard apple, white peaches, rambutan, persimmon	Fruits: apples, apricots, cherries, longon, lychee, nashi pears, nectarine, pears, peaches, plums, prunes, watermelon Vegetables: avocado, cauliflower, mushrooms, snow peas Sweeteners: sorbitol(420), mannitol(421), xylitol(967), maltitol (965), isomalt (953) & others ending in '-ol'
Suitable alternative low-FODMAP food source	Fruit: banana, blueberry, carambola, durian, grapefruit, grape, honeydew melon, kiwifruit, lemon, lime, mandarin, orange, passionfruit, paw paw, raspberry, rockmelon, strawberry, tangelo. Honey substitutes: maple syrup, golden syrup Sweeteners: any except polyols	Milk: lactose-free, rice milk Cheese:'hard' cheeses including brie, camembert Yoghurt: lactose-free Ice cream substitutes: gelati, sorbet Butter	Vegetables: bamboo shoots, bok choy, carrot, celery, capsicum, choko, choy sum, corn, eggplant, green beans, lettuce, chives, parsnip, pumpkin, silverbeet, spring onion (green only), tomato Onion/garlic substitutes: garlic-infused oil Cereals: gluten-free & spelt bread/cereal products	Fruits: banana, blueberry, carambola, durian, grapefruit, grape, honeydew melon, kiwifruit, lemon, lime, mandarin, orange, passionfruit, paw paw, raspberry, rockmelon Sweeteners: sugar (sucrose), glucose, other artificial sweeteners not ending in 'ol'

Table 1. Food sources of FODMAPs (where FODMAPs are problematic based on standard serving size) and suitable alternatives

FODMAP

Excess fructose

Lactose

Oligosaccharides (fructans and/or galactans)

Polyols

Problem high FODMAP food source

Fruits: apples, pears, nashi pears, clingstone peaches, mango, sugar snap peas, watermelon, tinned fruit in natural juice
Honey
Sweeteners: fructose, high fructose corn syrup
Large total fructose dose: concentrated fruit sources; large serves of fruit, dried fruit, fruit juice

Milk: cow, goat and sheep (regular & low-fat), Ice cream
Yoghurt (regular & low-fat)
Cheeses: soft & fresh (e.g. ricotta, cottage)

Vegetables: artichokes, asparagus, beetroot, Brussels sprout, broccoli, cabbage, fennel, garlic, leeks, okra, onions, peas, shallots.
Cereals: wheat & rye when eaten in large amounts (e.g. bread, pasta, couscous, crackers, biscuits)
Legumes: chickpeas, lentils, red kidney beans, baked beans
Fruits: watermelon, custard apple, white peaches, rambutan, persimmon

Fruits: apples, apricots, cherries, longon, lychee, nashi pears, nectarine, pears, peaches, plums, prunes, watermelon
Vegetables: avocado, cauliflower, mushrooms, snow peas
Sweeteners: sorbitol(420), mannitol(421), xylitol(967), maltitol (965), isomalt (953) & others ending in '-ol'

Suitable alternative low-FODMAP food source

Fruit: banana, blueberry, carambola, durian, grapefruit, grape, honeydew melon, kiwifruit, lemon, lime, mandarin, orange, passionfruit, paw paw, raspberry, rockmelon, strawberry, tangelo.
Honey substitutes: maple syrup, golden syrup
Sweeteners: any except polyols

Milk: lactose-free, rice milk
Cheese:'hard' cheeses including brie, camembert
Yoghurt: lactose-free
Ice cream substitutes: gelati, sorbet
Butter

Vegetables: bamboo shoots, bok choy, carrot, celery, capsicum, choko, choy sum, corn, eggplant, green beans, lettuce, chives, parsnip, pumpkin, silverbeet, spring onion (green only), tomato
Onion/garlic substitutes: garlic-infused oil
Cereals: gluten-free & spelt bread/cereal products

Fruits: banana, blueberry, carambola, durian, grapefruit, grape, honeydew melon, kiwifruit, lemon, lime, mandarin, orange, passionfruit, paw paw, raspberry, rockmelon
Sweeteners: sugar (sucrose), glucose, other artificial sweeteners not ending in 'ol'