FODMAP 101: Low FODMAP Diet Explained

FODMAPs Explained - AGN Roots Grass-Fed Whey

FODMAP 101 - 

What are the chances you deal with stomach issues like bloating, constipation, and gas daily? You're not alone. Let's start at the beginning.

What is Irritable Bowel Syndrome?

Irritable bowel syndrome (IBS) is a functional condition that affects 11% of the global population[1]. About 30% of the people who experience symptoms don't consult a doctor but rather learn what is possible via online publications and apply a few fundamental changes to their diets to land on a solution that works.

Everything you eat can have an impact on your body. In some cases, it can cause digestive issues or exasperate your IBS. By eating low FODMAP foods, limiting these reactions to tolerable levels or eliminating them is possible.

What exactly is the FODMAP diet, and how can it improve your digestive health?

In this guide, we'll review everything you need to know about FODMAP. With a base knowledge of low FODMAP foods, you could avoid digestive issues and improve your gut health for the long haul.

What are FODMAPs?

What does FODMAP stand for, exactly?


Fermentable carbohydrates are carbohydrates that break down by colonic bacteria via fermentation.  The fermentation method of digestion contrasts with enzymatic digestion, which does not create much gas or bowel irritation.


Oligosaccharides are carbohydrates that from when three to six units of simple sugars (monosaccharides) share bonds.


A disaccharide is the sugar formed when two monosaccharides share bonds.


Monosaccharides (fructose), also called simple sugars, are sugars in their simplest forms.


Polyols are hydrogenated monosaccharides and include foods like apples, cherries, pears, and plums.

Why do FODMAP Foods Cause Gas?

In short, these short-chain carbohydrates, when working through the small intestine, tend to rely heavily on bacteria fermentation which through osmosis pulls water into the colon, causing all kinds of discomfort.

Fermentation takes place when the small intestine is not capable of breaking down the sugars. As a result, the FODMAP food will make its way to the end of the intestine, meet its match, bacteria.

In other words, FODMAPs are short-chain carbs that often resist digestion. These carbohydrates are found naturally in various foods and impact everyone differently.

The amount of gas production as the byproduct of bacterial digestion is dependent on how much FODMAP food requires bacteria intervention to break down.

Types of FODMAPs

There are five main types of FODMAPs.

1.) Fructose

Fructose is a simple sugar. It's found in high fructose corn syrup, fruits, honey, and vegetables. 

Foods that contain fructose include:

  • Agave syrup
  • Honey
  • Most juices
  • Grapes
  • Peas
  • Zucchini
  • Apples

2.) Lactose

Lactose is a carb found in dairy products like milk. Though not all people with IBS are lactose intolerant, it can make IBS symptoms worse.

Foods tend to vary in lactose content, though. While some lactose-containing foods can trigger symptoms, some might not.

Foods that contain lactose include:

  • Cow and goat milk
  • Ice cream
  • Cheese
  • Yogurt
  • Baked goods containing milk

Learn More: Lactase Explained - How to break down Lactose?

3.) Fructans

Fructans are non-digestible carbs. They're found in barley, rye, wheat, and spelt. They're also found in vegetables like onions and garlic.

When gut bacteria act on fructans, it starts a fermentation process. This fermentation can offer some health benefits. However, it can also cause unwanted IBS symptoms.

Foods that contain fructans include:

  • Wheat
  • Barley
  • Rye
  • Garlic
  • Onions
  • Cashews
  • Watermelon
  • Asparagus
  • Bananas

4.) Galactooligosaccharides

Also known as galactans or GOS. This carb is found in legumes like chickpeas, lentils, and beans. Like fructans, galactans are non-digestible and can therefore cause IBS issues.

Foods that contain galactans include:

  • Soy products
  • Lentils
  • Beans
  • Pistachios
  • Oat milk
  • Lentils

5.) Polyols

Polyols are sugar alcohols that usually end in "-tol." A few include maltitol, mannitol, xylitol, and sorbitol. Some polys exist naturally in fruits and vegetables like blackberries and mushrooms.

Polys are also used as artificial sweeteners.

Foods that contain polys include:

  • Cauliflower
  • Stone fruits
  • Avocado
  • Blackberries
  • Corn
  • Celery
  • Sweet potatoes
  • Mushrooms
  • Artificial sweeteners

If you have IBS, you might not find that you're sensitive to every type of FODMAP. With that in mind, the FODMAP diet uses an elimination process. You'll eliminate every kind of FODMAP, then re-introduce one at a time.

The systematic process allows you to determine which foods cause your symptoms. Then, you can keep the foods you tolerate well within your diet.
Before following this process, make sure to speak with a doctor or qualified dietary professional. They can make sure you complete the process with your health in mind. A misdiagnosis of IBS related to FODMAPs with Irritable Bowler Disorder (IBD) is no small mistake.

How Do FODMAPs Affect the Body?

What exactly happens when you eat FODMAP diet foods?

Many FODMAPs will pass through the majority of your intestine without experiencing changes. FODMAPs are digestion-resistant. 

For some people, carbs function like FODMAPs, such as fructose and lactose. Sensitivity can vary between people. If you're sensitive to a specific FODMAP, it can cause digestive problems.

Once the FODMAP reaches your colon, the fermentation process begins. Then, your gut bacteria will use the fermented FODMAP for energy. This is the same process your body completes to feed friendly gut bacteria.

Positive gut bacteria can prevent health issues like irritable bowel syndrome, diarrhea, and eczema.

Friendly gut bacteria sometimes produce methane. Bacteria from FODMAPs, on the other hand, produce both hydrogen and methane which can cause you to experience pain, constipation, stomach cramps, gas, distention, and bloating.

Since FODMAPs are osmotically active, they can draw water into the intestine causing diarrhea and dehydration.

Who Should Use the FODMAP Diet?

Among patients with IBS, about 40% have mild symptoms, 35% have moderate cases, and 25% have severe IBS[2]. Some people don't recognize they're experiencing IBS. Here are a few potential symptoms you might want to look out for:

  • Pain and cramping
  • Diarrhea
  • Constipation
  • Alternating constipation and diarrhea
  • Fatigue
  • Difficulting sleeping
  • Anxiety and depression
  • Bowel movement changes
  • Gas and bloating
  • Food intolerance

About 70% of people with IBS report particular foods trigger their symptoms[3]. Unfortunately, there's no well-defined cause for IBS. Many people believe diet and stress can both have an effect.

Switching to the low-FODMAP diet could relieve your IBS symptoms. Reducing your symptoms could improve your quality of life.

In fact, following a low FODMAP diet food list could benefit patients with other functional gastrointestinal disorders (FGID). It could also help patients with inflammatory bowel diseases, such as ulcerative colitis and Crohn's disease.

If the low-FODMAP diet works for you, you might experience less:

  • Stomach pain
  • Constipation
  • Diarrhea
  • Bloating
  • Gas

Remember, everyone reacts to FODMAPs differently. How the low-FODMAP diet affects you could differ from someone else's experience. Keep an open mind and remain realistic before eating low-FODMAP diet foods.

Switching to a low-FODMAP diet could have a psychological benefit, too. Many digestive disturbances can cause stress and embarrassment. In some cases, irritable bowel syndrome is connected to anxiety and depression as well.

50% to 90% of the people who seek treatment for IBS have psychiatric disorders[4]. These include major depression, PTSD, social phobia, panic disorder, and generalized anxiety disorder. Scientists are still learning more about how the gut-brain connection works.

By switching to a low-FODMAP diet, you could reduce your anxiety and depression.

The Low FODMAP Diet Food List

Before you switch to a low-FODMAP diet, it helps to know which foods to add to your diet and which foods to avoid. Remember, the FODMAP diet works through an elimination process. You'll remove all high FODMAP foods from your diet first.

Then, you'll slowly add foods back into your routine to see which ones cause gastrointestinal symptoms.

First, let's talk about the foods you should add to your diet. This low-FODMAP diet food list can help you get started.

Make sure to add plenty of fish, meats, and eggs to your diet. These foods are usually well-tolerated. Check the label to make sure these foods don't contain FODMAP ingredients like high-fructose corn syrup or wheat.

When cooking, experiment with different fats and oils. For example, you can add olive oil to your next dish. Olive oil is high in omega-3 fatty acids, which provide health benefits like[5]:

  • Improving eye health
  • Fighting anxiety and depression
  • Fighting inflammation (which is associated with heart disease, cancer, and other conditions)
  • Promoting brain health during pregnancy
  • Alleviating menstrual pain
  • Improving sleep
  • Reducing ADHD symptoms in children
  • Improving the condition of your skin (reducing the risk of acne and premature aging)
  • Reducing the risk of certain cancers
  • Fighting autoimmune diseases (multiple sclerosis, type 1 diabetes, Crohn's disease, etc.)
  • Reducing metabolic syndrome symptoms
  • Reducing asthma in children and young adults
  • Improving mental disorders (bipolar disorder, schizophrenia, etc.)
  • Fighting age-related decline and Alzheimer's 
  • Reducing fat in the liver
  • Improving bone and joint health
  • Improving risk factors for heart disease

As you cook, add different spices and herbs into the mix, too. Herbs and spices can turn a bland dish into a flavorful creation.

Try to add nuts and seeds among your low FODMAP diet foods, including:

  • Sesame seeds
  • Peanuts
  • Cashews
  • Almonds
  • Macadamia nuts
  • Pine nuts

There are plenty of fruits you can eat that aren't high in fructose. For example, you can add blueberries, grapefruit, lemons, oranges, and strawberries to your diet.

There are low-FODMAP sweeteners you can use, too. Consider using molasses, stevia, and maple syrup to replace sugar alcohols.

Remember, there are some sources of lactose you can eat, like hard cheese. Consider aged, softer cheeses like camembert and brie, too. Otherwise, consider switching to lactose-free dairy products.

You can still have vegetables on a low-FODMAP diet, too! These vegetables include:

  • Bell peppers
  • Bok choy
  • Carrots
  • Cucumbers
  • Green beans
  • Kale
  • Lettuce
  • Spanish
  • Potatoes

You can also have grains like quinoa, rice, oats, and corn.

These low FODMAP diet foods aren't definitive, though. There are many other foods you might find are beneficial to your digestive health. Consider working with a professional dietitian to choose the right foods for your body.

Remember, everyone reacts to FODMAPs differently. You might find items on this low FODMAP food list you can't tolerate. Maybe there are high FODMAP foods you can tolerate.

The elimination diet will help you create a FODMAP diet that's right for you.

High FODMAP Foods to Avoid

It's not enough to use a low-FODMAP diet food list. If you want to improve your gut health, you'll need to know which foods to avoid, too. Otherwise, foods that are high in FODMAPs could cause gastrointestinal problems.

First, try to eliminate beer, fortified wines, fruit juice, soy milk, and milk from your diet. Avoid soft drinks with high-fructose corn syrup, too.

When removing dairy products from your diet, try to avoid fresh cheeses like ricotta and cottage cheese. Some whey protein supplements are high in FODMAPs, too. Remove milk, ice cream, sour cream, and most yogurts from your routine.

Learn More: How Much Lactose is in AGN Roots Grass-Fed Whey?

What fruits and vegetables do you have at home? Consider removing these items from your FODMAP diet:

  • Apples
  • Applesauce
  • Artichokes
  • Asparagus
  • Apricots
  • Beetroot
  • Blackberries
  • Boysenberries
  • Broccoli
  • Brussels sprouts
  • Cabbage
  • Canned fruit
  • Cauliflower
  • Cherries
  • Dates
  • Garlic
  • Fennel
  • Figs
  • Leeks
  • Mushrooms
  • Okra
  • Onions
  • Peaches
  • Peas
  • Pears
  • Shallots
  • Watermelon

Look in your pantry for wheat and barley products, too. Consider removing biscuits, crackers, bread, pasta, and most cereals from your diet. Avoid making pancakes or waffles for a while.

You'll also need to avoid certain legumes, including lentils, baked beans, soybeans, chickpeas, and red kidney beans.

Otherwise, avoid sweeteners like fructose, high fructose corn syrup, mannitol, sorbitol, maltitol, xylitol, and honey for a while. Instead, take your coffee black!

Remember, you can slowly reintroduce these foods back into your diet later on.

Benefits of a Low-FODMAP Diet

Before following this low-FODMAP diet food list, it helps to understand how it can change your life.

In one study, 66% of the patients who followed a low FODMAP diet were satisfied with their symptom control. All symptoms (bloating, abdominal pain, flatulence, lethargy) improved with the low FODMAP diet[6].

The low-FODMAP diet isn't for everyone, though. If your doctor hasn't diagnosed you with IBS, switching to low FODMAP diet foods could negatively impact your gut health.

Why? Most FODMAPs are prebiotics. Prebiotics support friendly bacteria in your gut.

Learn More: Prebiotics Explained

We need prebiotics to protect our bodies from harmful bacteria. Good gut bacteria could improve your immune system functions. They could help with obesity and depression, too.

Some gut bacteria even help form vitamin K and short-chain fatty acids, which promote a stronger gut barrier. This barrier protects the gut from viruses, bacteria, and inflammation.

In fact, short-chain fatty acids could even reduce your risk of cancer[7]. 
The FODMAP diet is ideal for anyone who has ongoing gut symptoms and hasn't responded to first-line dietary advice. It can also help if you haven't responded to stress management strategies.

Here are a few benefits you might experience by following the FODMAP diet.

Reduce Digestive Issues

One study compared IBS patients on the low FODMAP diet versus patients who received standard diet advice. After nine months, more patients who followed the low FODMAP diet reported satisfaction compared to the standard group (76% versus 54%)[8].

Many IBS patients experience stomach pain, reflux, flatulence, bowel urgency, and bloating. These symptoms could impact your social interactions and quality of life. Following a low-FODMAP diet could reduce your symptoms.

Switching to the FODMAP diet could help you manage your constipation, flatulence, and other digestive health issues.

Improve Your Quality of Life

After 15.7 months on the low FODMAP diet, 72% of participants reported satisfaction with their symptoms[9].

About 50 to 80% of patients with IBS experience symptom relief following FODMAP restriction.

Switching to a low-FODMAP diet could increase your energy levels. At the same time, you can limit your severe digestive symptoms. These changes could improve your overall quality of life.

Planning Your FODMAP Diet

Before you start eating FODMAP diet foods, you'll need a plan. There are three stages to the FODMAP diet. Before you get started, complete these steps to ensure the FODMAP diet is right for you.

Should I Talk to a Doctor about FODMAP?

Of course the first step is to get checked out by a practicing and licensed physician. Let them know if you're experiencing digestive symptoms. 

If IBD is ruled out, treating IBS is a great starting point where FODMAP knowledge will certainly serve you well. 

What is the First-Line Advice for the Low-FODMAP Diet?

Following the low-FODMAP diet is an intense process. Before you get started, your doctor might suggest you follow first-line strategies. Below is a compilation of common practices you may consider discussing with your physician.

Eat Regularly

First, set a schedule for regular, consistent meals. Eating regularly will ensure you're not overeating in one sitting. Sometimes, overeating can aggravate IBS symptoms.

Get Enough Fiber

You'll need fiber to improve your gastrointestinal and bowel health. 
If you're experiencing diarrhea, try foods with soluble fiber. These include squash, carrots, oats, and chia seeds.

If you're struggling with constipation, get a mix of soluble and insoluble fiber. Insoluble fiber includes fruits, vegetables, brown rice, quinoa, nuts, and seeds.

Learn More: Fiber Explained

Remove Irritants

Consider getting intentional with the removal of irritants from your diet that might impact your digestive health. These include alcohol, energy drinks, caffeine, and spicy foods.

Avoid High-Fat Meals

High-fat foods could trigger your IBS symptoms due to the natural proclivity of fats to stimulate colonic contractions. 

Avoid Sweeteners

Check the labels on your favorite foods and look for sugar alcohols, high fructose corn syrup, fructose, or honey. 

Learn More: Sweeteners 101

Manage Your Stress

Remember, the gut-brain connection could trigger IBS symptoms. Try to manage your stress levels. Consider picking up yoga or meditation for a while.

Learn More: La Vida Lorena 

What is Low-FODMAP Diet Preparation?

If you decide it's time to prepare for your FODMAP diet get rid of the high-FODMAP foods in your house. By removing temptation you have a shot. 

FODMAP Diet Stages

If you plan on following the low-FODMAP diet, you'll need to complete each stage. Here are the three stages of an effective FODMAP diet.


First, you'll need to avoid all high-FODMAP foods. Remove these foods from your diet for three to eight weeks. Instead, focus on your low-FODMAP diet food list.

Do you notice any change in your digestive health? Are you experiencing IBS symptoms less often? If it feels like your digestive health has improved, you can move on to the next step.


You can now start adding high-FODMAP foods back into your diet. The reintroduction stage will help you determine which FODMAPs you can tolerate. You'll also use this stage to determine your threshold level. Your threshold indicates the amount of FODMAPs your body can tolerate.

During the reintroduction stage, you'll test each food one by one, for three days at a time. Consider working with a trained dietitian during this process. You'll continue eating low-FODMAP diet foods during the reintroduction period.


Once you've completed the reintroduction stage, you should know which FODMAP foods you can and can't eat. Now, you can move onto the personalization stage. This stage is also called the modified low-FODMAP diet.

In this stage, you'll still need to restrict some high-FODMAPs. You might have found that low-FODMAP foods trigger your IBS, too. Using what you learned in the previous stage, you'll adapt your diet with your tolerance levels in mind. Consider the amount and type of each FODMAP you tolerated. You can add these foods to your routine now!

This step will help you remain flexible with your diet. It can also help you add more variety to what you eat. Following your personalized FODMAP diet can improve your quality of life and digestive health long-term. 

If your symptoms don't improve, make sure to review the foods you're eating. Look for ingredient lists to find high-FODMAPs. Then, cut these foods out.

Consider the stressors in your life, too. Even if you make changes to your diet, stress can still aggravate your IBS symptoms.

Remember, everyone reacts to FODMAP foods differently.

Keep that in mind as you begin this process.

FODMAP Diet Foods: Your Guide to Better Gut Health

Ready to start your journey toward better digestive health? With your list of FODMAP diet foods, you could reduce your IBS symptoms. Prepare to improve your quality of life with a happy, healthy gut! Looking for more ways to improve your digestive health? We're here to help. 

Consider switching to a grass-fed whey to improve your gut health today!

[1] Canavan, Caroline et al. “The epidemiology of irritable bowel syndrome.” Clinical epidemiology vol. 6 71-80. 4 Feb. 2014, doi:10.2147/CLEP.S40245
[2] Industry Council., IFFGD. “Statistics.About IBS, 25 Mar. 2021,
[3] Monsbakken, K W et al. “Perceived food intolerance in subjects with irritable bowel syndrome-- etiology, prevalence and consequences.” European journal of clinical nutrition vol. 60,5 (2006): 667-72. doi:10.1038/sj.ejcn.1602367
[4] Lydiard, R B. “Irritable bowel syndrome, anxiety, and depression: what are the links?.” The Journal of clinical psychiatry vol. 62 Suppl 8 (2001): 38-45; discussion 46-7.
[5] Hjalmarsdottir, Freydis. “17 Science-Based Benefits of Omega-3 Fatty Acids.Healthline, Content Created by Healthline and Sponsored by Our Partners, 15 Oct. 2018,
[6] Nawawi, Khairul Najmi Muhammad, et al. “Low FODMAP Diet Significantly Improves IBS Symptoms: an Irish Retrospective Cohort Study.European Journal of Nutrition, Springer Berlin Heidelberg, 13 Sept. 2019,
[7] Drago, Lorenzo. “Probiotics and Colon Cancer.” Microorganisms vol. 7,3 66. 28 Feb. 2019, doi:10.3390/microorganisms7030066
[8] Ross, Erin, et al. “The Low FODMAPS Diet and IBS: A Winning Strategy.Journal of Clinical Nutrition & Dietetics, IMedPub, 8 Apr. 2016,
[9] Whelan, K., et al. “The Low FODMAP Diet in the Management of Irritable Bowel Syndrome: an Evidence‐Based Review of FODMAP Restriction, Reintroduction and Personalisation in Clinical Practice.Wiley Online Library, John Wiley & Sons, Ltd, 15 Jan. 2018,


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