All About Lentils & FODMAPs

This Explore An Ingredient: Lentils will cover canned lentils as well as dried lentils.

For dried we will discuss the 3 varieties listed on the Monash App, using the terminology that Monash uses:

  • Green Lentils (also often called Brown Lentils)
  • Red Lentils
  • Le Puy Lentils (also often called French Green Lentils or lentilles du Puy)

Three kinds of lentils in wooden scoops, on a white painted wooden surface

Are Lentils Low FODMAP?

You might have seen lentils on some high FODMAP food lists. We are here to set things straight.

There are low FODMAP serving sizes of lentils, but the recommended serving sizes vary depending on the type of lentil and how it was prepared.

Most importantly, in our Test Kitchen analysis the volumes that are actually low FODMAP are NOT the volumes stated on the Monash app (as of September 2019) for three out of their four entries.

NOTE: As of 12/21 Monash University updated their canned green lentil app entry and it now aligns with our recommendations below. Canned, drained green lentils are low FODMAP in 46 g amounts (as they were before) but Monash has not adjusted their volume to ¼ cup.

This is particularly important to U.S. FODMAPers, or anyone who measures by volume.

We also used the USDA as reference and our weights and volumes align with theirs.

The Short Story

 We have had discussions with Monash about discrepancies between their volumes and weights as presented on the app as of September 2019.

They have instructed us (and you) to pay attention to the weights. 

We have created an easy-to-use guide for you to understand what volumes correspond to those weights. Our volumes are very different from the ones on the Monash App, so if you measure by volume this will be on interest to you.

Here is our chart of recommended low FODMAP volume amounts of lentils to consume, based upon the recommended low FODMAP weights by Monash.

lentil graph

Our Chart Explained

  • BLUE represents published low FODMAP weights of lentils by Monash University. These are confirmed low FODMAP amounts.
  • GREEN represents the volumes FODMAP Everyday® has determined match the low FODMAP Monash weights. If you are measuring by volume, we recommend you pay attention to this column.
  • RED represents the volumes that Monash says matches their weights. 

As you can see, for the weights that Monash has determined to be low FODMAP amounts,  our volumes were about half of their stated volumes. This is a significant difference.

The exception is the Le Puy lentils. Per the Green Light low FODMAP 30 g serving, we came up with 3 tablespoons and they came up with 2 tablespoons, but we can assume that they used Australian tablespoons, which are larger, and so our measurements pretty much match.

Please read our article When Is A Tablespoon Not A Tablespoon? For more information on Australian tablespoons.

The Takeaway

If you measure by volume and you want to measure out the amount that Monash has determined to be Green Light low FODMAP, then you should measure out HALF of what Monash has listed on their app (9/2019). The exception is the Le Puy lentils, which we believe are represented correctly. 

If you want the LONG story, which is complicated and involves a lot of math, please jump to the end of this article.

Consider Canned Lentils: Water Soluble GOS & Fructans

Lentils contain both GOS and fructans, and the amounts will depend on variety.

These FODMAPs are water-soluble, which is why it is recommended that you buy canned lentils and drain them. A good portion of the FODMAPs will drain away with the liquid. Therefore you can eat a larger amount of canned, drained lentils than you can of dry lentils, cooked from scratch.

Drain your canned lentils thoroughly in a fine-meshed strainer, THEN measure or weigh the amount for you to eat or use in a recipe. (More below).

Check out our recipe for Tempeh Lentil Chili, which showcases canned, drained lentils.

Lentil Nutrition

Lentils are a complex carbohydrate, low in fat and calories, and high in protein and fiber.

Lentils are also high in potassium, manganese, phosphorus, iron and are a very rich source of folate.

Lentils are naturally gluten-free.

Choosing Your Lentil

Green Lentils:

These are also referred to as brown lentils and if you find a recipe that simply calls for “lentils”, then these are the kind you want.

These green (brown) lentils are the same used in most canned lentil products and for classic lentil soup.

Check out our recipe for Lentil Salad with Greens & Yogurt, which showcases canned, drained lentils.

Red Lentils:

Red lentils come whole or split. Make sure you choose the correct type for your individual recipe.

Red lentils cook very quickly and become quite soft and even mushy, which can be used to their advantage, such as in Indian dal.

Check out our recipe for Chicken & Lentils, which showcases red lentils.

Le Puy Lentils:

These small, very dark green lentils are also referred to as French Green Lentils and Lentilles du Puy. They are known for their flavor and how they hold their shape, making them exceptional for salads, in particular.

How To Buy

Know what your recipe is calling for or what you want from your choice of lentil, as they are not interchangeable.

For instance, classic Indian dal will take advantage of the fact that red lentils will cook down to a silky, lovely mashed texture.

Salads will be exceptional when made with Le Puy French green lentils, as they hold their shape, are visually attractive and retain some toothsome texture.

Traditional lentil soup begs for simple green (brown) lentils.

If you have the option of buying lentils in bulk, this can be a very economic approach, and you can buy just what you need.

For lentilles du Puy you will most likely will have to order online, unless you have a very well-stocked gourmet foods store nearby. Remember, true lentilles du Puy will have an AOC designation.

AOC stands for appellation d’origine controlee. It is a French certification system that guarantees the designation of origin. For instance the AOC designation will guarantee that your Roquefort cheese comes from Roquefort and that your lentilles du Puy come from that region of France.

How To Store

As with any dry bean or legume, store them airtight in a cool, dry place.

For canned, simply refer to the use-by date on the label.

How To Prep

Sort through your dry lentils as there could be little stones or lentils that are just not right. Simply pick those out and discard.

Rinse your lentils in a wire-meshed strainer under cool water to remove any dust or powdery debris.

How To Cook

Individual recipes will dictate, so follow those directions.

Lentils do not have to be soaked, as do some heartier and hardier beans.

A general rule of thumb is a ratio of 3:1 water to dry lentils. Bring both water and lentils to a boil in a covered pot, reduce heat to a simmer and cook until tender. Red lentils will cook much faster than green/brown or Le Puy.

Generally speaking, green lentils will cook in about 20 minutes and red lentils less than 10 minutes.

You can use stock in lieu of water for more flavor.

Use a large pot as dried lentils will at least double and sometimes even triple in volume during cooking.

Many cooks like to salt lentils after cooking, not during, as it is said salt toughens lentils if it is added to water during cooking.

Some cooks prefer to cook lentils like pasta, in plenty of water, cooking till tender and then draining.

The Long Story Of Lentil Volume Measuring

Monash University is based in Australia and they use the metric system when cooking.

The Monash app offers volume amounts for food entries and then there are corresponding weights, of which you can choose either grams or ounces.

While FODMAP Everyday®is a global resource, we are based in the U.S. and we use volume measurements in our cooking, as do Americans in their homes. All of our FODMAP Everyday®recipes are presented in imperial and metric, so that anyone in the world can use our recipes and information.

We know volume measurements are important to the U.S. consumer.

As I worked on lentils for this article and our lentil recipes, it became clear to me that something wasn’t lining up. It appeared that the volumes and weights on the Monash app did not match one another, which I discerned from our own weighing and measuring in our Test Kitchen.

I also referenced the FDA as an additional resource. Their weights and volumes align with our findings.

I contacted Monash in regards to their lentil entries on the app and was directed to use their posted weights and not the volumes.

How FODMAP Everyday®Assessed Lentils

In our Test Kitchen we use a digital scale and we use calibrated volume measuring implements. Please refer to our article Measuring By Volume for further information on what “calibrated volume measuring implements” means.

Precision & Accuracy

I cooked each lentil three different times. Our volume measurements were taken 10 times for each food item, on each of the three separate occasions, and the average volume was recorded.

The volumes per weight that are listed in the Monash app did not correspond to our findings (or to the FDA ). Most distressingly, the Monash volumes were in most cases 100% larger in volume than our results. This huge, statistically significant discrepancy is what encouraged us to investigate further.

Monash App Amounts Are Cooked & Drained

Monash said that they performed their lab tests on cooked and drained lentils. They said that for the dry lentils that they cooked them according to the instructions “given on the pack”, with no further explanation. For canned lentils they weighed them after draining.

One common approach in test kitchens that I have worked in is to prepare dry lentils with water in a 3:1 ratio, water to lentils. This is how we prepared our lentils.

Look & Learn?

In the past, Monash has directed us to use the image accompanying each food entry to help us assess the food tested.

Apparently with lentils, although the weights provided are for cooked lentils, which was confirmed in our contact with Monash, they decided that the image of raw lentils was more attractive and used that instead. So in this case the image did not help us understand what the entry was presenting.

So, How Much Can I Eat?

Monash told us to use the weights listed on their app, so we did. Then, in our Test Kitchen we used their weights to discern the actual volumes that we should be eating in order to comply with a Green Light low FODMAP volume.

Our chart above in this article shows you the low FODMAP volumes that you can eat. 

About Canned Lentils

Canned lentils were drained before measuring by Monash and we followed suit.

Monash states that 46 g of canned, drained lentils are low FODMAP. They state that this volume amount is equal to ½ cup.

In our Test Kitchen measurements ½ cup of drained, canned lentils was equal to 82 g, which means that if you have been using the Monash volume measurement to plan your low FODMAP meals you have been eating way too much canned, drained lentils.

Our ¼ cup weighed 41 g, which is much closer to the recommended weight by Monash.

Drained Weight is Vastly Less

Make sure you drain your canned lentils before measuring or weighing.

One, 15.5 ounce (439 g) can of lentils equals 8.75 ounces (246 g) of drained lentils. Note the very large weight difference between drained and straight out of the can in the image below.

Image of Undrained and Drained Lentils

Dry Green Lentils

Monash has lab tested cooked green (brown) lentils and they are low FODMAP in amounts of 23g. (Note that this is much less than the recommended canned, drained amount). Their corresponding volume is ¼ cup.

Green (brown) lentils in a black wooden scoop

In our testing, a low FODMAP amount of cooked green (brown) lentils that weighs 23 g are equal to a scant 2 tablespoons, roughly HALF the volume of what Monash states.

For the record, our 2 tablespoon volume measurement came to 25 g.

Also for the record, Monash states that 46 g of green (brown) cooked lentils are Moderate for FODMAPs. They state that this is equal to ½ cup. In our testing ½ cup of cooked green (brown) lentils weighed 100 g.

Remember, Monash has told us to go by their weights. They say a low FODMAP amount of cooked green (brown) lentils is 23 g. This is very close to our volume measurement of 2 tablespoons, NOT their stated ¼ cup.

Dry Red Lentils

Monash has lab tested cooked red lentils and they are low FODMAP in amounts of 23g. Their corresponding volume is ¼ cup.

Dried Red lentils in a brown wooden scoop, closeup

In our testing, a low FODMAP amount of red lentils that weighs 23 g is equal to approximately 2 tablespoons, again roughly HALF the volume of what Monash states.

For the record, our 2 tablespoon volume measurement came to 24 g.

Also for the record, Monash states that 46 g of red cooked lentils are Moderate for FODMAPs. They state that this is equal to ½ cup. In our testing ½ cup of cooked red lentils weighed 96 g.

Please note, Monash has told us to go by their weights. They say a low FODMAP amount of cooked red lentils is 23 g. This is very close to our volume measurement of 2 tablespoons, NOT their stated ¼ cup.

French Green Le Puy Lentils

At first glance, this app entry might appear confusing. This is because Monash states that 2 tablespoons of cooked Le Puy lentils weigh 30 g, but they also state that ½ cup weighs 90 g.

lentilles du Puy in a light wooden scoop, closeup

At first this would seem to not make sense, because ½ cup equals 8 tablespoons – EXCEPT in Australia, where their tablespoon is larger.

Their tablespoons, being a fourth larger than the rest of the world’s tablespoons, explains their math as presented.

Monash has lab tested Le Puy lentils and they are low FODMAP in amounts of 30g. Their corresponding volume is 2 tablespoons – but note that these are Australian tablespoons.

In our testing, a low FODMAP amount of Le Puy lentils that weighs 30 g equals about 3 tablespoons, which closely resembles their 2 Australian tablespoon measurement.

For the record, our 2 tablespoon volume measurement came to 24 g.

If you made it down to here, THANK YOU for sticking with me:) Now, go eat your lentils in the right amounts!