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Low-FODMAP bulking: a full 3,500-calorie day

By Iron Gut · Updated 25 October 2026

Most low-FODMAP meal plans are written for a normal appetite. If you train hard and want to gain, you need two or three of those plates, and the portions are where it gets tricky. This page shows one full day from The Build Plan at about 3,520 calories and 212 g of protein, with each meal and its numbers.

What low-FODMAP means for a big eater

FODMAPs are a group of carbohydrates that some people struggle to absorb: fructose, lactose, fructans, galactans and polyols. Gut bacteria ferment them fast, and they draw water and gas into the gut as they go [1]. Garlic and onion are two of the biggest sources of fructans, which is why low-FODMAP recipes leave them out.

The catch for a lifter is portion size. A food can sit inside its low-FODMAP serving at a normal plate and go over it once you double the plate. So the way to eat 3,500 calories on low-FODMAP food is to keep the limited foods at their serving and build the extra calories from foods that carry few FODMAPs at any size: rice, potatoes, meat, fish, eggs, lactose-free dairy and oils.

If you have ongoing gut symptoms, see a doctor or a dietitian before you change your diet. This page shows a day of food for general information.

The day, meal by meal

The day below is day 4 of the 3,500-calorie week in The Build Plan. Calories and protein are estimates from the book.

Breakfast: maple oat and rice porridge (785 calories, 48 g protein)

Oats carry FODMAPs once the serving gets large, so the porridge stops the oats at half a cup and makes the bowl big with cooked rice, lactose-free milk and whey isolate. You get a breakfast that runs close to 800 calories without stacking the oats.

Mid-morning: popcorn, peanut and dark chocolate mix (440 calories, 14 g protein)

Popcorn gives you volume, and the peanuts stay at 28 g. This snack runs higher in fat than the rest of the day, so it fits on a day when the meals are lean.

Lunch: ginger soy beef rice bowl (1,005 calories, 68 g protein)

The bowl comes to 875 calories and 65 g of protein on its own. The 3,500 day adds 100 g of cooked rice, which brings 130 calories, and that one change is how the plan moves a meal up a calorie level. Ginger, scallion greens and tamari carry the flavor in place of garlic and onion.

Dinner: pork chop, mash and green beans, with roasted carrots (960 calories, 61 g protein)

The pork chop plate comes to 785 calories and 59 g of protein, and the maple-roasted carrots add 175 calories. Potatoes and carrots stay low in FODMAPs at full portions, so they carry a lot of the calories on this diet.

Evening: vanilla chia pudding with strawberries (330 calories, 21 g protein)

The pudding closes the day. If you want more protein, the book lets you stir in half a scoop of whey isolate for 55 calories and 12 g of protein.

How to adjust the day

You can scale this day up or down with the starches. Each 100 g of cooked white rice adds about 130 calories, and each extra 150 g of potato adds about 105 calories, so you can move a meal up or down without touching the limited foods. The Build Plan runs weeks at about 3,000, 3,500 and 4,000 calories, and each day is added up at its level.

Two habits keep a big low-FODMAP day working. Cook the rice, beef and soup in one session so the week runs off the fridge, and keep one fruit per meal so the fructose stays spread out across the day.

Want the whole week?

The Build Plan has 64 recipes, one per page, and week plans at three calorie levels, with the portions worked out. You can see the plans here. If you're also avoiding gluten, the gluten-free version runs the same calorie levels.

To check packaged food for hidden garlic and onion, the free Label Cheat Sheet shows the six words to scan for.

FAQ

Can you bulk on a low-FODMAP diet?

You can. You build the calories from foods that stay low in FODMAPs at large portions, such as rice, potatoes, meat, fish, eggs and lactose-free dairy, and you keep foods with a serving limit, such as oats, at that serving.

How much protein is in this 3,500-calorie day?

The day comes to about 212 g of protein, with 48 g at breakfast, 68 g at lunch and 61 g at dinner, plus the snacks.

What replaces garlic and onion in these recipes?

Garlic-infused oil, the green tops of scallions, ginger and tamari carry the flavor. The fructans in garlic stay in the solids, so a strained infused oil keeps the taste without them.