Low FODMAP Diet Portion Sizes: How Much Can I Eat?

After we ask, “What Can I Eat?” after being told we should follow the Low FODMAP diet, the next question is often, “How Much Can I Eat?”

We are told we can have almonds, but then we see them listed on some high FODMAP lists, as well as on a list of Low FODMAP foods. How many almonds are okay? When do they tip from Low FODMAP to high? Twenty blueberries are okay according to the Monash University Smartphone App but let’s say you come across a recipe that calls for ½ cup; how does that translate? And what does it mean if Monash Green Lights 1 ½ tablespoons of salsa, but Australian tablespoons are a different volume than everyone else’s in the world? (Yes, that’s true. More on that later).

Confused? Yeah, we were too! This article is meant to address your Low FODMAP diet portion sizes questions, but first, a little primer:

Use Your Tools

We love our Monash University Smartphone App. Frankly, we wouldn’t be able to navigate the Low FODMAP diet without it and we highly suggest that you download it, if you haven’t already.

Australian Tablespoons

Tablespoons in Australia equal 20 ml. Everywhere else in the world considers a tablespoon to be 15 ml. This means that for most of us, when we see something on the Monash Smartphone app (an Australian-based App) that lists food amounts in “tablespoons” that we can actually have more of the food than we initially think if we live outside of Australia!

Use Your Smarts

The list of Low FODMAP foods in the Monash University Smartphone App will be displayed in multiple ways. It will be listed either in volume or by count, such as those 10 blueberries, or ½ cup bean sprouts. Then, each of those foods will also have a corresponding weight; you can tell the app to show you ounces or grams. But the problem for many of us is that we don’t know what anything looks like in terms of ounces or grams, which is why we are writing this article in Low FODMAP diet portion sizes. 

Counting out 20 berries is easy, but what does 30 grams of dark chocolate look like? And what about avocado? The app says 1/8 an avocado is Low FODMAP, but if you know what a Hass avocado looks like (small) next to a Florida avocado (huge) you know that the designation of “1/8 an avocado” isn’t that helpful. In cases like that you have to look at the weight, and again, most of you probably don’t know what 20 grams of avocado looks like. But we know and we are going to show you here. Let’s get to the pictures!

*Please note that we are showing you the largest amount of an ingredient that the Monash University Smartphone app states is “Green Light” and Low FODMAP. It does not necessarily mean that this is the largest amount that one can consume, without triggering symptoms or that Monash has assessed as the upper limit in terms of FODMAPs (see Sugar, below). Please work with your registered dietitian to assess your own personal tolerances and needs.

Almonds & Walnuts

Here you can see what 1 Low FODMAP serving of almonds looks like (10 whole almonds/12 g) versus 1 Low FODMAP serving of walnuts (10 halves/30 g). Take note of specific language within the Monash University Smartphone App. The Low FODMAP diet portion sizes for almonds is for whole almonds, whereas the walnut serving is for walnut halves.

Avocado

Monash recommends 1/8th an avocado as one serving, but what does that look like? Take a good look at the amount of avocado below; this is what a Green Light Low FODMAP serving, 20 g/.75 ounce of avocado looks like. Avocados vary tremendously by size. A Florida avocado can weigh 2 pounds/910 grams. A Hass avocado will average at about 6 ounces/170 grams. Obviously “1/8 an avocado” means very little, but 20 g/.75 ounce is the same no matter where you live or what kind of avocado you start with! 

Cheddar Cheese, cubes and shredded and sliced

Yes, you CAN have some dairy products on the Low FODMAP diet. Monash's list of Low FODMAP foods includes “2 slices” of cheddar cheese. Well, here is what their 1 1/2 ounce/ 40 gram size serving looks like in a block, shredded and in slices. Enjoy a cheese sandwich or melt some on corn chips for nachos to serve with our salsa (see below).

Low FODMAP Salsa, BBQ Sauce & Ketchup

We love our condiments as much as the next person - but we need to watch our FODMAP intake. Thankfully we can still have Low FODMAP Salsa (1 1/2 tablespoons/30 g), Low FODAMP BBQ Sauce (2 tablespoons/ 46 g) and Low FODMAP Ketchup (1 sachet/ 13 g), as long as we pay attention to servings sizes. In the images below you might be thinking that the ketchup amount looks tiny. We successfully dipped over a dozen French fries in there! And by the way, we didn’t know what “1 sachet” was either. Turns out it is equivalent to a little more than 2 teaspoons. 

Dark Chocolate & Milk or White Chocolate

The Low FODMAP diet portion size for dark chocolate is set at “5 squares”, which doesn’t tell us much. Luckily Monash also details that this is equal to 30 g - and 15 g for milk and white chocolates - but what does that serving size look like? Quite a bit actually. Check out the amounts below, including the same amount of dark chocolate in chip/morsels form (it’s about 3 tablespoons). Yes, you can have chocolate on the Low FODMAP diet!

Sugar

Plain, white table sugar is recommended at 1 tablespoon servings by Monash University - but those are Australian tablespoons. A closer look tells us that they suggest 14 g, which is more similar to 1 tablespoon plus 1/2 teaspoon of sugar everywhere else in the world. This might not seem like a big difference, but when you add these extra teaspoons up in a recipe, they can make a huge difference. Also, please note that while plain white table sugar is a disaccharide, it is not a FODMAP, due to the fact that it has equal amounts of glucose and fructose. Sugar is only recommended in small amounts by Monash based upon general healthy eating guidelines. You can eat more and use more sugar in recipes - just use common sense and keep it to a minimum. We make and eat cupcakes, but not for everyday!

Oats

Oats are another ingredient that can create confusion. Are they gluten-free or not? Are they Low FODMAP? Oats themselves are gluten-free, however, they can be an issue for some people for two reasons: they can be cross-contaminated with gluten during harvesting and/or processing, and they contain avenin, which is a protein in oats that is similar to gluten and might need to be avoided if it triggers symptoms for you. Monash says that oats are Low FODMAP in servings of 1/2 cup/52 g. Note that this is for 1/2 cup of raw oats, which when cooked, makes quite a generous bowl of oatmeal, as you can see below.

Raisins

Speaking of grapes, let’s look at dried grapes, aka raisins. The Monash app says a Low FODMAP serving size is 1 tablespoon/13 g. Again, these are Australian tablespoons, which means that the rest of us can rest easy knowing we can have a heaping tablespoon amount - which actually goes a long way as a snack, in cookies, a bowl of oatmeal or any way you would like to use them.

Blueberries & Strawberries

Not all berries are created equal! Blueberries are Green Light approved by Monash University in amounts of 20 berries/28 g. How does this translate to volume? It equals about 3 U.S. tablespoons. Strawberries, on the other hand, are listed on the Smartphone App as having a high detectable FODMAPs. 8 medium sized strawberries show as red in the Monash app. Blueberries will give you more bang for your FODMAP buck.

Gluten-Free Pasta

Perhaps, like us, the pasta entry in the Monash Smartphone App left you scratching your head. The Low FODMAP serving of 1 cup/ 145 g is for cooked pasta. But how do you know how much to start with raw? And what about all the different shaped pastas? We cooked and compared very curly rotelle pasta and also long strands of spaghetti, because they were as different as pasta shapes can get. To our great surprise each of them measured about a cup at the same 145 g weight! So even though the image in the Monash Smartphone App shows a penne type shape, it turns out that they are all pretty much the same weight per cup. For your information, we cooked 12-ounce packages of pasta and the result is about 700 grams cooked, so this size package gives you 5 scant Low FODMAP diet portion sizes.