Food is one common trigger for digestive conditions such as irritable bowel syndrome (IBS).

Avoiding high FODMAP foods is the cornerstone of some of the most common IBS diets.

But is it really worth cutting out those fermentable carbohydrates and following a low-FODMAP diet?

Let’s do some digging and find out!

What are FODMAPS?

FODMAPs are a collection of carbohydrates that contribute to IBS symptoms like gas, bloating and stomach pains.

To spell this out:¹

Fermentable

Oligosaccharides

Disaccharides

Monosaccharides

Polyols

Summary

• FODMAP is an anagram for carbohydrates that could cause/worsen IBS symptoms

Why choose a FODMAP diet for IBS?

Some (but not all) carbohydrates are poorly absorbed in the small intestine. As a result, they move further through the gut and ferment in the large intestine.

In people with IBS, this can trigger symptoms such as bloating, constipation, wind, diarrhoea, stomach pain and flatulence.

The guiding theory of a low FODMAP IBS diet is to replace high FODMAP foods that are poorly digested with low FODMAP foods that easily break down in the stomach.

This decreases the fermentation of sugars in the large intestine. Consequently, this can reduce bloating, constipation and other IBS symptoms.

However, IBS sufferers aren’t all sensitive to the same high FODMAP foods. To help reduce IBS symptoms, a dietitian may recommend you eliminate high FODMAP foods for a short period.

They are then gradually reintroduced in phases to identify which exact foods you are most sensitive to. It can also show which are better tolerated.

Summary

• It has been proven that some carbohydrates (FODMAPs) can trigger IBS
• The FODMAP diet can help you distinguish which cause your symptoms and which are ‘safe’

How do you start a low-FODMAP diet?

A low-FODMAP diet is not quite as simple as cutting out all high-FODMAP foods and focusing on low-FODMAP foods. It usually involves the following three stages:

1. Restriction

This stage usually lasts a few weeks and requires strict avoidance of high-FODMAP foods.

Once you find adequate relief of IBS symptoms then you can move onto the next stage.

2. Re-introducing foods

This next step requires reintroducing high-FODMAP foods to see which type and amount of high-FODMAP foods are affecting you the most.

It is recommended that you reintroduce foods one at a time – and it is recommended that you use a dietician to help guide you through this process.

3. Making it work for you

This stage allows you to know which FODMAP foods you need to restrict, and which ones are actually fine to consume.

For example, you may be fine eating a piece of wheat bread every day but may want to avoid cauliflower all the time.

As you can see, a low FODMAP diet is a significant dietary intervention. And unless you have diagnosed IBS and have exhausted all other IBS diet options, it can do more harm than good.

If you don’t want to be so strict…

The lists of high- and low-FODMAP foods below show how complex and restricted a low FODMAP diet can be.

Just to reiterate, a low FODMAP diet isn’t for everyone. But that’s not to say you can’t take inspiration from some of the theory.

For example, keeping a food diary to track the severity of your symptoms against what you’ve consumed.

Most of us can’t remember exactly what we eat on a day-to-day basis. This is why it can be helpful to write it down.

This visibility allows you to recognise patterns between your diet and IBS symptoms. With this knowledge you could then reduce or eliminate a food for a short period to see if it has an impact on symptoms.

This is a simple but effective way to, see how an individual food may be causing your digestions problems.

How to start a food diary for IBS

1. Write down everything you eat daily, the time you ate it, and the severity and time of your IBS symptoms on the same day.
2. If you recognise a pattern where eating a certain food seems to regularly coincide with a rise in your digestion problems, consider eliminating this from your diet for a few weeks.
3. During this elimination period, continue to keep a food diary and track your symptoms.
4. After this period, gradually reintroduce the food and record any changes in your symptoms.
5. Repeat with other foods if necessary.

It’s always recommended that any changes to diet are done in consultation with your GP or a dietitian.

Summary

• There are several stages to a formal FODMAP diet, all of which help you to determine which foods are a problem for you
• It is recommended that you consult a trained dietician for help with this
• Keeping a food diary can also help you find out which foods you may need to avoid

What are FODMAPs foods?

FODMAPs can be found in varying amounts in a wide variety of foods.

Some foods contain just the one, e.g. only fermentable carbs, whereas others can contain several different types.

High-FODMAP foods

In many cases, high FODMAP foods are to blame for IBS symptoms. So, it makes sense to cut them out, right?

But whilst there’s growing evidence to show restricting these foods can drastically improve IBS symptoms, it takes serious commitment.

Here is a comprehensive list of high FODMAP foods which you should avoid/reduce if you want to follow this diet (especially in the first reduction stage).²

• High-FODMAP vegetables/legumes

1. Garlic (including garlic salt, garlic powder) – should be avoided entirely if possible
2. Onions (including onion powder) – should be avoided entirely possible
3. Artichoke
4. Asparagus
5. Bakes beans
6. Beetroot
7. Broad beans
8. Butter beans
9. Cassava
10. Cauliflower
11. Celery
12. Falafel
13. Pickled / fermented vegetables, e.g. sauerkraut
14. Kidney beans
15. Mangetout
16. Mung beans
17. Mushrooms Peas
18. Kidney beans
19. Cabbage
20. Soybeans
21. Spring onions

• High-FODMAP fruit

1. Apples
2. Apricots
3. Avocado
4. Bananas (ripe)
5. Blackberries
6. Blackcurrants
7. Cherries
8. Currants
9. Dates
10. Figs
11. Goji berries
12. Grapefruit (over 80g)
13. Guava (unripe)
14. Lychee
15. Mango
16. Nectarines
17. Peaches
18. Pears
19. Pineapple
20. Plums
21. Pomegranate
22. Prunes
23. Raisins (over 1 tbsp)
24. Sultanas
25. Tined fruit in pear / apple juice
26. Watermelon

• High-FODMAP meat

1. Chorizo
2. Sausages

• High-FODMAP cereals, grains and nuts

1. Wheat (and products containing it, e.g. biscuits, bread, noodles)
2. Almond flour/meal
3. Amaranth flour
4. Barley
5. Bread
6. Carob flour / powder
7. Cashews
8. Chestnut flour
9. Couscous
10. Einkorn flour
11. Freekeh
12. Gnocchi
13. Granola
14. Muesli
15. Pistachios
16. Rye
17. Semolina
18. Spelt flour

• High-FODMAP sweeteners, condiments, spreads, etc.

1. Agave nectar
2. Fructose
3. Gravy (if it contains onion)
4. High fructose corn syrup
5. Hummus
6. Honey
7. Jam
8. Molasses
9. Pesto
10. Stock cubes
11. Vegetable pickle
12. Most sugar-free sweets
13. Sweeteners (inulin, isomalt, lactitol, maltitol, mannitol, sorbitol, xylitol)
14. Tzatziki dip

• High-FODMAP drinks

1. Beer (more than one bottle)
2. Apple and raspberry cordial (50-100% real juice)
3. Orange cordial (20-50% red juice)
4. Fruit / herbal tea with apple
5. Apple, pear or mango fruit juice
6. Orange juice (if over 100ml)
7. Fruit juices (any in high quantities)
8. Kombucha
9. Meal replacement shakes containing milk
10. Rum
11. Fizzy drinks with high fructose corn syrup
12. Soy milk
13. Sports drinks
14. Tea (if strong or with added soy milk)
15. Wine (more than 1 glass)
16. Whey protein (unless lactose free)

• High-FODMAP dairy foods

1. Buttermilk
2. Ricotta cheese
3. Cream
4. Custard
5. Gelato
6. Ice cream
7. Kefir
8. Cow’s milk
9. Goat’s milk
10. Evaporated milk
11. Sheep’s milk
12. Sour cream
13. Yoghurt

Summary

• As you can see, there are a lot of foods to be aware of if you want to go low-FODMAP

Low FODMAP foods

It’s not all doom and gloom though, there are also lots of foods that are perfectly fine to eat while following a low-FODMAP diet.

Here are some of the most common ‘safe’ foods and the quantities you should limit certain foods to.

• Low-FODMAP vegetables/legumes

1. Alfalfa
2. Bamboo shoots
3. Beansprouts
4. Beetroot
5. Black beans (45g)
6. Bok choy / pak choi
7. Broccoli (35g)
8. Brussels sprouts (2 sprouts)
9. Butternut squash (35g)
10. Cabbage (70g)
11. Callaloo
12. Carrots
13. Celeriac
14. Celery (less than 5cm of stalk)
15. Chicory leaves
16. Chickpeas (42g)
17. Chili – if tolerable
18. Chives
19. Collard greens
20. Corn (1/2 cob)
21. Courgette (65g)
22. Cucumber
23. Aubergine (80g)
24. Fennel
25. Green beans
26. Green pepper (75g)
27. Ginger
28. Kale
29. Lentils (in small amounts)
30. Lettuce
31. Marrow
32. Okra
33. Olives
34. Parsnip
35. Snow peas (5 pods)
36. Pickled gherkins
37. Large pickled onions
38. Potato
39. Pumpkin
40. Radish
41. Red peppers
42. Spring onions (the green part)
43. Seaweed
44. Chard
45. Baby spinach
46. Squash
47. Sun-dried tomatoes (4 pieces)
48. Swede
49. Swiss chard
50. Sweet potato (65g)
51. Tomato (1 small / 1/4 a can)
52. Turnip (1/2 a turnip)
53. Water chestnuts
54. Zucchini

• Low-FODMAP fruit

1. Ackee
2. Unripe bananas (1 medium)
3. Blueberries (45g)
4. Cantaloupe melon (120g)
5. Cranberry (1tbsp)
6. Clementine
7. Coconut cream (75g)
8. Coconut flesh (50g)
9. Dragon fruit
10. Lingonberries
11. Grapes
12. Guava
13. Honeydew / Galia melons (80g)
14. Kiwifruit (2 small)
15. Lemon (including juice)
16. Lime (including juice
17. Mandarin
18. Orange
19. Passion fruit
20. Papaya
21. Pineapple
22. Plantain
23. Prickly pear
24. Raspberry (30 berries)
25. Rhubarb
26. Strawberry
27. Tamarind

• Low-FODMAP meat/meat substitutes

1. Beef
2. Chicken
3. Chorizo
4. Foie gras
5. Kangaroo
6. Lamb
7. Pork
8. Prosciutto
9. Quorn
10. Turkey
11. Cold cuts, e.g. ham, turkey breast
12. Processed meat (check ingredients)

• Low-FODMAP fish/seafood

1. Canned tuna
2. Fresh cod
3. Fresh haddock
4. Fresh plaice
5. Fresh Salmon
6. Fresh Trout
7. Fresh Tuna
8. Plain crab
9. Plain lobster
10. Plain mussels
11. Plain oysters
12. Plain prawns
13. Plain shrimp

• Low-FODMAP cereals, grains and nuts

1. Wheat free bread
2. Gluten-free bread
3. Corn bread
4. Rice bread
5. Spelt sourdough bread
6. Potato flour bread
7. Wheat- / Gluten-free pasta
8. Wheat bread (1 slice)
9. Almonds (10 almonds)
10. Cream crackers (4 crackers)
11. Oatcakes (4 cakes)
12. Shortbread biscuit (1 biscuit)
13. Brazil nuts
14. Bulgur (44g cooked serving)
15. Buckwheat
16. Brown / wholegrain rice)
17. Chestnuts
18. Plain potato crisps
19. Cornflour / maize
20. Cornflakes (14g)
21. Gluten-free cornflakes
22. Corn tortillas (3 tortillas)
23. Crackers
24. Flaxseed / linseed (1tbsp)
25. Hazelnuts (10 hazelnuts)
26. Macadamia nuts
27. Millet
28. Mixed nuts
29. Oats
30. Peanuts
31. Pecans (10 halves)
32. Pine nuts
33. Polenta
34. Popcorn
35. Porridge / oat-based cereals
36. Potato flour
37. Pretzels
38. Quinoa
39. Pasta (100g cooked)
40. Rice
41. Rice cakes
42. Rice flour
43. Chia seeds
44. Hemp seeds
45. Poppy seeds
46. Pumpkin seeds
47. Sesame seeds
48. Sunflower seeds
49. Tortilla chips
50. Walnuts

• Low-FODMAP sweeteners, condiments, spreads, etc.

1. Aspartame
2. Acesulfame K
3. Almond butter
4. Barbeque sauce
5. Capers in vinegar
6. Dark chocolate (5 squares)
7. Milk chocolate (4 squares)
8. White chocoalte (3 squares)
9. Chutney (1tbsp)
10. Dijon mustard
11. Fish sauce
12. Golden syrup (1tsp)
13. Glucose
14. Glycerol
15. Strawberry jam
16. Raspberry jam (2tbsp)
17. Maple syrup
18. Marmalade
19. Marmite
20. Mayonnaise (no garlic / onion ingredients)
21. Miso paste
22. Mustard
23. Oyster sauce
24. Pesto sauce (less than 1 tbsp)
25. Peanut butter
26. Rice malt syrup
27. Saccharine
28. Shrimp paste
29. Soy sauce
30. Sriracha hot chili sauce (1 tsp)
31. Stevia
32. Sweet and sour sauce
33. Sucralose
34. Sugar
35. Tahini pate
36. Tomato sauce / ketchup (2 sachets)
37. Vegemite
38. Apple cider vinegar (2 tbsp)
39. Balsamic vinegar (2 tbsp)
40. Rice wine vinegar
41. Wasabi
42. Worcestershire sauce (the onion and garlic content is acceptably low, making it low-FODMAP)

• Low-FODMAP drinks

1. Beer (1 drink)
2. Vodka (limited intake advised)
3. Gin (limited intake advised)
4. Whiskey (limited intake advised)
5. Wine (1 drink)
6. Coffee (without milk or up to 250ml lactose free milk)
7. Coconut milk (125ml)
8. Coconut water (100ml)
9. Drinking chocolate powder
10. Fruit juice (low-FOSMAP fruits only, 125ml)
11. Lemonade (low quantities)
12. Egg protein powder
13. Rice protein powder
14. Whey protein isolate powder
15. Soya milk made with soy protein
16. Sugar free soft drinks (low quantities)
17. Black tea
18. Chia tea
19. Fruit and herbal tea (no apple added)
20. Green tea
21. Peppermint tea
22. White tea
23. Water

• Low-FODMAP dairy foods, eggs and alternatives

1. Butter
2. Brie
3. Camembert
4. Cheddar
5. Cottage cheese (2 tbsp)
6. Cream cheese (2 tbsp)
7. Feta
8. Goat
9. Halloumi (40g)
10. Monterey Jack
11. Mozzarella
12. Paneer (2 tbsp)
13. Parmesan
14. Ricotta (2 tbsp)
15. Swiss cheese
16. Eggs
17. Margarine
18. Almond milk
19. Hemp milks (125ml)
20. Lactose-free milk)
21. Macadamia milk
22. Oar milk (30ml)
23. Rice milk
24. Sorbet
25. Soy protein (avoid soy beans)
26.  Tempeh
27. Tofu (drained and firm varieties)
28. Whipped cream
29. Coconut yoghurt
30. Greek yoghurt (23g)
31. Lactose-free yoghurt
32. Goat’s yoghurt

• Low-FODMAP herbs, spices and cooking ingredients

1. Most herbs and spices (avoid chili, garlic, onion)
2. Avocado oil
3. Canola oil
4. Coconut oil
5. Olive oil
6. Peanut oil
7. Rice bran oil
8. Sesame oil
9. Soybean oil
10. Sunflower oil
11. Vegetable oil
12. Acai powder
13. Baking powder
14. Baking soda
15. Cacao powder
16. Cocoa powder
17. Gelatine
18. Ghee (1tbsp)
19. Icing sugar
20. Lard
21. Mango powder (1tsp)
22. Nutritional yeast
23. Salt
24. Soybean oil

Summary

• Thankfully, there are a lot of ‘safe’ low-FODMAP foods around, which may be worth implementing into your diet to see if you experience a difference

Before you consider a low FODMAP IBS diet

Following a low FODMAP IBS diet is not a decision to take lightly. Only attempt it if:

• Your IBS is formally diagnosed by your GP
• You’ve tried other less restrictive diet strategies already (e.g. increasing your fibre intake and probiotics)
• You’re recommended this diet by a FODMAP trained dietitian. Don’t attempt it alone – you need ongoing professional nutrition advice and support to implement this diet plan effectively

This final point is particularly important.

If this is a diet change you would like to initiate, careful implementation is crucial.

A FODMAP trained dietitian can assess if it’s appropriate for your IBS symptoms and also ensure what you’re eating continues to be nutritionally sufficient.

This is not an allergy diet

Eliminating high FODMAP foods isn’t a long-term solution.

This is where IBS diets can differ from allergy diets.

It’s important to recognise, IBS is not caused by a food allergy. It has nothing to do with your immune system.

Whereas diets for food allergies and intolerances often involve permanent exclusion of an allergen, this is not usually required in IBS diets.

For example, after the initial elimination period in a FODMAP diet, most IBS sufferers can start to tolerate small to moderate quantities of high FODMAP foods.

Consider that food may not be causing your IBS

Remember, diet is only one cause of IBS. If lifestyle factors, such as stress, are the trigger of your IBS symptoms, making behavioural changes could be more valuable.

In addition, if you suffer with food anxiety of any form, or have other underlying health conditions, it’s particularly important to seek medical guidance before pursuing an IBS diet.

Summary

• A low-FODMAP diet is a big commitment and shouldn’t be taken lightly
• Increasing your fibre and probiotics could help your IBS before going for a FODMAP diet
• Eliminating FODMAP foods isn’t a long-term solution, as different people can tolerate different types/amounts of FODMAP foods
• Keep in mind that food may not be causing your IBS, as it can also be linked to stress, food anxiety and other underlying health conditions

The final say

• FODMAPS are different groups of carbohydrates which may affect/worsen IBS symptoms
• A low-FODMAP diet is sometimes recommended to help determine which FODMAP foods affect you
• FODMAP diets can be very restrictive and should not be viewed as a long-term solution
• If you have been diagnosed with IBS and want to try a FODMAP diet, it is recommended that you consult a registered dietician to help

Last updated: 10 August 2021