There are so many health benefits associated with eating a plant-based diet. However, for those with digestive issues such as irritable bowel syndrome (IBS) or inflammatory bowel disease (IBD), it can be challenging to find plant-based options that won’t trigger symptoms.
The low FODMAP diet is a temporary elimination-type diet which involves avoiding certain types of carbohydrates that can be difficult to digest for some people.
The goal of a low FODMAP diet is to help reduce digestive symptoms and improve overall gut health. For some people this can make following a plant-based diet so much more enjoyable!
In this blog post, we’ll take a closer look at what a low FODMAP diet entails, potential challenges and considerations, and tips on how to succeed on a low FODMAP plant-based diet.
What are FODMAPs?
FODMAP is an acronym that stands for Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols. Sounds like a mouthful, but these are simply types of carbohydrates that are found in many foods.
These short-chain carbohydrates are not well absorbed in the small intestine. They then travel to the large intestine where they are fermented and used as fuel by bacteria.
This fermentation process produces hydrogen gas which can cause gas, bloating, abdominal pain, and other digestive symptoms in some people.
FODMAPs are naturally present in many fruits, vegetables, grains, and dairy products, as well as in some sweeteners and additives used in processed foods and supplements.
It is important to remember that most of these FODMAP foods are healthy foods and not everyone is sensitive to them.
How Does a Low FODMAP Diet Work?
The low FODMAP diet was developed by a team of researchers at Monash University in Melbourne, Australia as a way to manage digestive symptoms. The diet works as a system and involves three phases: elimination, reintroduction/challenge, and personalization.
These three phases help you discover what your food triggers are and how to eventually incorporate them back into your diet without causing symptoms. Because, ultimately, most of these foods are high in fiber, prebiotics and probiotics which your gut needs for long-term health.
Let’s break down each of these phases and what they entail:
1. Elimination – Low FODMAP
This is the phase that most people think of when they hear Low FODMAP diet. During the elimination phase, high FODMAP foods are avoided for a period of 2 weeks up to 6 weeks. This phase allows the digestive system to calm down and symptoms to improve.
The elimination phase requires careful attention to food labels and should involve working with a registered dietitian to ensure adequate nutrient intake.
2. Reintroduce – Challenge High FODMAP foods
Once you feel significant improvement to your overall symptoms and have been symptom free for 3-5 days you can begin the Challenge phase.
A single food from each FODMAP group is reintroduced one at a time, starting with a small quantity and then increasing portion size over a 3 day period. After that, you wait for 3-5 days before starting your next challenge with another FODMAP group.
You should keep a food symptoms diary to keep track of foods challenged and your level of symptoms.
This process usually takes 8-12 weeks and helps determine which specific FODMAPs are causing symptoms, which foods can be tolerated and in what amounts, so that the diet can be personalized to each individual’s needs.
The personalization phase is all about expanding your diet so that you can enjoy more foods and still maintain control over your symptoms.
Using your food symptoms diary you can begin to rate your symptoms and categorize foods into three catagories:
- 1. Green – these foods caused little to no symptoms and are well tolerated.
- 2. Yellow – these foods were tolerated in small amounts but caused symptoms in larger amounts (dose dependent).
- 3. Red – these foods caused the most symptoms and were poorly tolerated.
This will help you navigate what foods to start adding back into your diet. The goal is to not avoid the “red” foods forever but maybe wait a few months before challenging them again to see if your tolerance has improved.
Who Would Benefit from a Low FODMAP Diet?
The low FODMAP diet is usually recommended if you have been diagnosed with IBS (irritable bowel syndrome) by your doctor and have already ruled out celiac disease, diverticulitis and other conditions with similar symptoms to IBS.
It may also be suggested for people with inflammatory bowel disease (Crohn’s disease, ulcerative colitis) or SIBO (small intestinal bacterial overgrowth).
It is estimated that around 75% of people with IBS experience symptom relief on a low FODMAP diet. If you fall into the 25% who don’t improve, I would discuss other potential causes with your health practitioner.
You never want to diagnose yourself or start on this diet without the recommendation from your doctor. The low FODMAP diet can be tricky and complex and is best tackled with the guidance of an experienced registered dietitian.
It is also important to note that a low FODMAP diet is not a long-term solution, but rather a short-term approach to identify trigger foods and create a personalized plan for a healthy, sustainable diet.
Challenges & Considerations for Plant-Based Eaters
The challenge for vegans and vegetarians is that FODMAPs are found in staple foods like fruits, vegetables, whole grains, nuts, beans, lentils, and soy foods. These are all healthy foods that we rely on heavily to meet our nutrition needs.
But don’t give up! You may find it comforting to know that for every high FODMAP food there is a low FODMAP swap. The key is starting with the recommended serving size and then adjusting from there according to your individual tolerance.
It is possible to be vegan or vegetarian and follow a low FODMAP diet. It just takes some thought and planning and hopefully some guidance from a registered dietitian for added support.
The following are a few nutrition considerations for plant-based eaters:
Since a lot of high FODMAP foods are also high in fiber this can make it difficult to meet your fiber needs especially during the elimination phase.
The good news is that there are some great lower in FODMAP prebiotic fiber sources to choose from like: kiwis (2), unripe banana, cooked and then cooled potatoes or rice (a great source of resistant starch along with green bananas), cabbage (1/2 cup), walnuts (10 halves), flaxseeds (1 Tbsp), chia seeds (2 Tbsp), rolled oats (1/2 cup), buckwheat, canned lentils (1/2 cup), and canned chickpeas (1/4 cup).
Pay attention to the ingredients inulin, chicory root, and fructo-oligosaccharides (FOS) which are often added to a lot of dairy-free products and supplements. These sources of fiber are considered high FODMAP.
A lot of the staple plant proteins are high in FODMAPs. Most beans, lentils and some soy products (soy milk, soft/silken tofu, whole mature soybeans) fall into the high FODMAP category. Thankfully, there are a few exceptions.
Beans & Lentils
Canned & rinsed lentils at 1/2 cup (46g) or canned & rinsed chickpeas at 1/4 cup (42g) can be considered low FODMAP if kept at that serving size.
Soy products lower in FODMAPs include: firm/extra-firm tofu, tempeh, edamame, and miso. Refer to the blog post Pros and Cons of Soy for more information on soy, FODMAP servings and benefits of soy.
Also include high protein lower FODMAP grains such as 1 cup quinoa, brown rice, millet, 3/4 cup buckwheat, 1/2 cup oats, 2/3 cup teff.
Nuts & Seeds
Nuts like cashews and pistachios are high FODMAP, but adding lower FODMAP nuts and seeds are not only great fiber sources but they also provide added protein.
These include: 2 Tbsp seeds (chia, hemp, pumpkin, sunflower), 1 Tbsp flaxseeds, 2 Tbsp peanut butter, 32 peanuts (28g), walnuts (10 halves), 20 macadamia nuts (40g), 10 almonds.
Seitan is an awesome source of protein and is low FODMAP. Even though it is made from wheat gluten, it is a protein and not a carbohydrate.
However, most store bought seitan contain high FODMAP seasonings like garlic and onion so it is best to make your own using vital wheat gluten*. 1/4 cup or 30g is considered low FODMAP and contains 25g protein (*Disclaimer: as an Amazon Associate I earn from qualifying purchases).
As long as you are including a variety protein sources in the right amount you should be able to meet your protein needs just fine.
If you are an athlete or your protein needs are higher, including a low FODMAP friendly protein supplement can be beneficial. Refer to tip number 6 (below) under 9 tips to help you succeed on a low FODMAP plant-based diet.
Getting enough iron is important for growth and development and for making hemoglobin which provides oxygen to all parts of the body, preventing anemia.
Some of the best sources of plant-based iron come from high FODMAP beans and lentils. This is why you should “milk” the 1/4 cup chickpeas (canned & rinsed) and 1/2 cup lentils (canned & rinsed) to not only provide fiber and protein, but to also some iron.
Other good iron sources are 1 cup kale (137g), bok choy (75g), quinoa (155g cooked), firm tofu (170g), 1/2 cup oats (52g), 2/3 cup teff, 2 Tbsp seeds (pumpkin, hemp, sesame), 1 Tbsp flax, peanut butter.
To help increase absorption of iron make sure to avoid tea and coffee with meals and include a rich source of vitamin C: lemon, lime, strawberries, bell pepper, kiwi. You can also increase your iron by cooking in a cast iron skillet!
Calcium is important for bone and heart health. Thankfully there are a few low FODMAP plant-based sources to choose from.
A few good calcium sources are: kale, bok choy, cabbage, orange, broccoli florets (3/4 cup or 75g), canned lentils (1/2 cup), canned chickpeas (1/4 cup), firm/extra-firm tofu, tempeh, 2/3 cup teff and calcium fortified plant milks (1 cup unsweetened almond, macadamia, rice, or hemp milk).
Eating enough calcium is important but it’s also important to make sure you are getting enough vitamin D in order to absorb the calcium you are eating in addition to doing weight-bearing exercise. More on vitamin D in a few.
Zinc is a mineral that helps the immune system fight off invading bacteria and viruses to keep you healthy. It also helps heal wounds and is important for proper taste and smell.
Good plant-based sources of zinc include: quinoa, brown rice, oats, buckwheat, firm/extra-firm tofu, tempeh, low FODMAP nuts & seeds, 3/4 cup broccoli florets, and…again…canned lentils and chickpeas.
Including enough plant sources of omega 3 fatty acids is essential. Omega 3s play an important role in your overall health. Check out my previous blog post to learn more about the benefits and The Best Vegan Omega 3 Sources.
You can find low FODMAP alpha-linolenic acid (ALA) sources from: flaxseeds, flaxseed oil, hemp seeds, chia seeds, walnuts, firm tofu, tempeh, edamame.
To ensure you are getting enough DHA and EPA, some people recommend taking an algae based omega 3 supplement daily containing at least 250 mg of combined DHA and EPA.
Vitamin B12 is an important nutrient that helps your body form red blood cells, maintain nerve function, helps make DNA, and converts fat and protein into energy.
Whether you are following a low FODMAP diet or not, if you are vegan or vegetarian (or over the age of 50) it is recommended that you take a B12 supplement (cyanocobalamin).
This is because B12 is not found in plant-based foods and as you age your body doesn’t produce as much hydrochloric acid which is important for B12 absorption .
Some foods are fortified with B12 like nutritional yeast (which happily is considered low FODMAP at 1 Tbsp!), but you would have to use a lot of nutritional yeast with every meal consistently in order to meet your B12 needs. So, taking a supplement is still recommended.
Absorption of B12, especially in supplement form, is poor which is why it is generally recommended to take around 50 mcg daily or 2,000 mcg every week (much higher than the RDI value of 2.4 mcg daily).
There are so many benefits to vitamin D beyond bone health and helping your body absorb calcium. Vitamin D can also support a healthy heart, help decrease inflammation and boost immune function.
Unfortunately, there are very few foods that naturally contain vitamin D. Some foods like plant milks are fortified with it, but this would not provide you with enough. This holds true regardless of whether or not you are following a low FODMAP diet.
They call it the sunshine vitamin because your body can also make vitamin D when your body is exposed to sufficient sunlight (at least 10-15 minutes a day). However, there are many factors that affect the efficiency of this.
Because of this and the importance of vitamin D for your immune system, it is often recommended to take a daily supplement of 1,000-2,000 IU daily.
The “Gentle” FODMAP Approach
If all of this information about the low FODMAP diet sounds completely overwhelming, I hear you! For some, it can create a lot of anxiety which is not helpful for your symptoms.
The good news is that there is an easier approach that you can try first. It’s called the “gentle” FODMAP diet which is a more relaxed version of the low FODMAP diet.
This more gentle version still incorporates the same three phases (elimination, challenge, personalize). The difference is, during the elimination phase you only avoid the really high FODMAP foods that are statistically more likely to create symptoms. This provides more flexibility instead of having to restrict all high FODMAP foods.
The “gentle” FODMAP approach can be a good option if you:
- Are underweight and at risk for nutritional deficiencies.
- Have a history of disordered eating.
- Already have a lot of dietary restrictions due to food allergies, sensitivities or other medical health conditions.
- Are a child and still growing or are elderly.
- Are pregnant.
- Don’t have access to a dietitian or FODMAP trained specialist.
- Find the standard low FODMAP diet too difficult to follow.
Refer to Monash University for more on the “gentle” FODMAP approach.
9 Tips to Help You Succeed on a Low FODMAP Plant-Based Diet:
So, if you are plant-based and your doctor has recommended that you try a low FODMAP diet then these tips are for you!
1. Don’t try to do it alone!
A FODMAP trained registered dietitian can help you troubleshoot and provide you with the support you need to be successful.
2. Limit the Elimination Phase
It might be best to limit the elimination phase to 2 weeks (depending on symptom improvement) in order to avoid extra dietary restrictions for a prolonged period of time.
3. Meal Plan!
Planning ahead can ensure you are meeting your nutrition needs and help keep you satisfied. Balance your meals by including all major food groups: low FODMAP whole grains, plant proteins, fruit/vegetables, nuts and seeds.
4. It’s All About Portions
Pay close attention to portions. A “low FODMAP” food can turn into a high FODMAP food just by doubling the portion size. Use the Monash App to identify which foods and portions are considered low and high FODMAP.
You can also search for low FODMAP certified products and utilize their food/symptom diary to help you keep track.
5. Be a Food Label Detective
Get comfortable reading food labels for FODMAP ingredients. This can be tricky! Read Monash’s blog on Label Reading for more details.
6. Shake it Up
This is optional, but you can always add a protein shake for extra fuel. A lot of supplements are loaded with high FODMAP ingredients and additives but there are certified low FODMAP supplements out there.
I like HUM Core Strength vanilla protein powder*. It is vegan and certified low FODMAP with fewer ingredients. Just be cautious with protein supplements. I would probably wait until after the elimination phase to add it in (*Disclaimer: as an Amazon Associate I earn from qualifying purchases).
7. Supplement As Needed
Taking a good vegan multi-vitamin daily can help ease your mind that you are meeting all the nutrients of concern. One of my favorites is Complement.
An important non-diet related tip is to take good care of yourself! Practice stress management techniques like meditation and deep breathing.
Getting enough sleep can be a difficult task to achieve sometimes but the pay off is huge. Lack of sleep can put stress on your gut and affect your digestive health.
Aim for daily movement or gentle exercise such as yoga, Tai Chi. All of these things can help decrease inflammation and move you closer to a symptom-free life.
9. Complementary Treatments
Another beneficial non-diet tip is the use of complementary treatments. Both Cognitive behavioral therapy and acupuncture can be effective treatments for IBS1. Just another tool to add to your tool box.
Low FODMAP Seasoning & Sweeteners
Let’s talk flavor! A big challenge is that both onions and garlic are high in FODMAPs. This forces you to be more creative when it comes to flavoring your food and using sauces.
Fortunately, there are low FODMAP alternatives that you can use instead. Swap out onions for chives and use garlic infused olive oil in place of garlic. You can also use a low FODMAP garlic and onion replacement powder. I really like the Gourmend brand because it contains quality ingredients.
Soy sauce is considered low FODMAP up to 2 Tbsp. Tamari and coconut aminos are also great low FODMAP options. Adding in up to 2 Tbsp of miso is another way to add some umami flavor.
Fody is a good resource for low FODMAP sauces, marinades, salsas, and salad dressings.
High FODMAP sweets and sweeteners to watch out for: agave syrup, honey, high fructose corn syrup, isomalt, mannitol, molasses, sorbitol, xylitol. Most sugar-free gum, mints and candies contain one of these ingredients.
Low FODMAP sweets and sweetener alternatives: 2 heaping tsp cocoa or cacao powder, 100% maple syrup, rice malt syrup, sugar (brown, white, raw, confectioner’s, beet), stevia, and dark chocolate! (5 pieces or 30g).
Low FODMAP Vegan Swaps
For an easy reference, check out the list below for a few low FODMAP Vegan Swaps:
How to Succeed on a Low FODMAP Plant-Based Diet
As you can probably tell by now, the low FODMAP diet is not straight-forward. If you are plant-based it definitely presents some challenges, but it is possible!
By following the above tips and recommendations you can succeed on a low FODMAP plant-based diet. Just remind yourself that the elimination phase is only temporary.
This is a short-term approach to help you identify your personal trigger foods and create an individualized plan for a healthy, sustainable and symptom-free diet for the long-term.
If you’re looking for meal planning ideas, I created a Plant-Based Low FODMAP 7 Day Meal Plan. It’s available under Services and Plant-Based Meal Plans.