Plain grits are low FODMAP and safe for most people following a low-FODMAP diet. Grits are made from ground corn, and Monash University, the leading authority on FODMAP testing, has tested corn-based foods and rated them as low FODMAP at standard serving sizes. That said, what you add to your grits and the type you buy can change the picture.
Why Corn-Based Grits Are Low FODMAP
FODMAPs are specific types of carbohydrates that ferment in the gut and trigger symptoms like bloating, gas, and abdominal pain in people with IBS. Corn doesn’t contain significant amounts of any of these fermentable carbohydrates. Monash University has tested corn in several forms, including corn on the cob, polenta, tortillas, and popcorn, and found them all to be low FODMAP at a standard or half serving.
Grits and polenta are essentially the same thing: ground dried corn. The main difference is the grind size and regional tradition. Since polenta appears on both the Monash University and Stanford Hospital low-FODMAP food lists, grits made from the same base ingredient carry the same FODMAP profile. Stanford’s Digestive Health Center explicitly lists grits as a suitable wheat-free grain on a low-FODMAP diet. Both white and yellow corn grits are safe, as the processing method and corn variety don’t meaningfully change the FODMAP content.
Watch Out for Flavored and Instant Varieties
Plain stone-ground grits are straightforward: just ground corn. But pre-packaged and instant varieties sometimes contain additives worth checking. Quaker Original Instant Grits, for example, lists degerminated white corn grits, salt, calcium carbonate, iron, B vitamins, BHT, and citric acid. Ingredient screening tools flag at least one ingredient in this product as potentially high FODMAP, though the core corn grits themselves are fine.
The bigger risk comes from flavored instant grits. Varieties labeled “butter flavor,” “cheese,” or “country bacon” often contain milk solids, onion powder, garlic powder, or high-fructose corn syrup. Onion and garlic are among the highest-FODMAP foods, and even small amounts in powdered form can trigger symptoms. If you’re buying instant grits, flip the package over and scan the ingredient list before assuming they’re safe.
How to Keep Your Grits Low FODMAP
The simplest approach is buying plain grits (stone-ground, quick-cook, or instant with no added flavoring) and seasoning them yourself. For cooking liquid, water is the safest choice. If you want a creamier result, use lactose-free milk or a plant-based milk that’s low FODMAP, like almond milk in small quantities.
Butter is a reliable choice for richness. Monash University has tested butter and gives it a green light at one tablespoon (about 19 grams). Butter is high in fat but contains virtually no carbohydrates, which means it carries no FODMAPs. A pat of butter with salt and pepper is the classic preparation and happens to be one of the safest for a sensitive gut.
For toppings and mix-ins that work well:
- Cheese: Hard and aged cheeses like cheddar, Parmesan, and Swiss are naturally very low in lactose and generally well tolerated. Soft cheeses are riskier unless labeled lactose-free.
- Garlic-infused oil: You can’t eat garlic pieces, but garlic-infused olive oil delivers the flavor without the FODMAPs. The problematic compounds in garlic are water-soluble, not fat-soluble, so they don’t transfer into oil.
- Maple syrup: A drizzle of real maple syrup turns grits into a breakfast side. Maple syrup is low FODMAP at one tablespoon.
- Bacon and eggs: Plain proteins are FODMAP-free. Crumbled bacon and a fried egg on top of grits is a classic combination that stays well within safe territory.
- Fresh herbs: Chives, basil, and green parts of scallions add flavor without FODMAP concerns.
Portion Size Considerations
Most corn-based foods test low FODMAP at a full standard serving, which for a cooked grain side dish is roughly three-quarters of a cup. Grits expand significantly during cooking, so a quarter cup of dry grits typically yields about a cup of cooked grits. Staying within a normal single-bowl portion keeps you well within the tested safe range. There’s no evidence that larger portions of plain corn grits become high FODMAP, but the general principle of the low-FODMAP diet is to stick to tested serving sizes during the elimination phase.
If you’re stacking multiple low-FODMAP foods in the same meal, keep in mind that FODMAPs from different sources can add up. A bowl of grits on its own is unlikely to cause issues, but grits plus several other borderline foods in the same sitting could push your total FODMAP load higher than expected.