Is Spinach Low FODMAP? Fresh, Frozen & Cooked Spinach Guide
Spinach is low FODMAP and safe for IBS. Learn about fresh, frozen, baby spinach, and cooked vs raw volume differences on the low-FODMAP diet.
Yes, spinach is low FODMAP. Fresh spinach, baby spinach, and frozen spinach are all confirmed low in FODMAPs at standard serving sizes. Spinach is one of the most nutrient-dense vegetables available and is a reliable choice for people following a low-FODMAP diet. It is rich in iron, folate, vitamins A and C, and numerous antioxidants, making it an important food to include in a diet that can sometimes feel nutritionally limited.
The one thing to be aware of with spinach is the dramatic volume difference between raw and cooked. A large bowl of raw spinach cooks down to just a couple of tablespoons, which means it is easy to eat much more spinach in cooked form than you realize.
Why Is Spinach Low in FODMAPs?
Spinach is low in FODMAPs because it contains minimal amounts of fructose, fructans, GOS, lactose, and polyols. Leafy green vegetables in general tend to be FODMAP-friendly because their carbohydrate content is low — most of their weight comes from water, fiber, and micronutrients rather than fermentable sugars.
Monash University has tested baby spinach and confirmed it as low FODMAP at 75g, which is a generous serving of about 2-3 cups of raw leaves. This is one of the larger tested serving sizes for vegetables, reflecting the fact that spinach simply does not contain meaningful amounts of problematic carbohydrates.
FODMAP Breakdown: Spinach
| Form | Serving Size | FODMAP Level | Notes |
|---|---|---|---|
| Baby spinach (raw) | 75g (~2-3 cups) | Low | Generous safe serving |
| Mature spinach (raw) | 75g | Low | Slightly tougher leaves |
| Cooked spinach | 1/2 cup (75g) | Low | Represents much more raw spinach |
| Frozen spinach | 75g (thawed, drained) | Low | Equivalent to large raw volume |
| Spinach in smoothies | 1 cup raw (30g) | Low | Common smoothie addition |
What Is the Raw Versus Cooked Volume Difference?
This is the most important practical consideration with spinach. Raw spinach has very high water content and a lot of air between the leaves, which means it reduces dramatically when cooked.
Roughly speaking, 6 cups of raw spinach cooks down to about 1 cup. This means that a serving of cooked spinach represents a much larger quantity of actual spinach than an equivalent volume of raw spinach.
For example, if you saute a large bag of fresh spinach (about 300g raw) until wilted, you end up with less than a cup of cooked spinach. You have just eaten four times the tested low-FODMAP serving size. While spinach is low FODMAP even at moderately larger servings, this concentration effect is worth keeping in mind.
Practical guideline: A half-cup of cooked spinach is a reasonable serving that keeps you well within low-FODMAP limits. If you are eating raw spinach in a salad, 2-3 cups is a comfortable amount.
How to Use Spinach on a Low-FODMAP Diet
Spinach is one of the most versatile vegetables in a low-FODMAP kitchen. Here are some practical applications.
Salads
Baby spinach makes an excellent salad base. It is tender, mild-flavored, and pairs well with a wide range of toppings. Try it with sliced strawberries (low FODMAP at 5 berries), hard cheese (which is naturally low in lactose), walnuts (low FODMAP at 10 halves), and a simple olive oil and lemon dressing.
Smoothies
A handful of raw spinach (about 30g or 1 cup) adds nutrition to smoothies without significantly affecting flavor. Blend with a ripe banana (firm bananas are lower FODMAP), a splash of lactose-free milk, and some frozen blueberries for a nutrient-packed, low-FODMAP smoothie.
Cooked Dishes
Sauteed spinach with garlic-infused oil is a classic side dish that remains FODMAP-safe. Wilt spinach in a hot pan with garlic-infused olive oil, a pinch of salt, and a squeeze of lemon. It takes about 2 minutes and pairs well with grilled protein and rice.
Spinach also works well stirred into oatmeal (savory oats are underrated), mixed into egg dishes like frittatas and omelets, or layered into lasagna with lactose-free cheese.
Frozen Spinach Convenience
Frozen spinach is a time-saving staple. It is already blanched and chopped, so you can add it directly to soups, stews, pasta sauces, and casseroles. Keep a bag or box in the freezer for quick meals. Frozen spinach retains most of its nutritional value and has the same FODMAP profile as fresh.
How Does Cooking Affect Spinach’s FODMAP Content?
Cooking does not increase the FODMAP content of spinach per gram. However, because cooking reduces volume so dramatically, you end up consuming more spinach per apparent serving. This is a portion control issue rather than a FODMAP chemistry issue.
Boiling spinach and draining the water may slightly reduce any water-soluble components, but since spinach’s FODMAP content is already very low, this effect is negligible.
One cooking consideration: if you are making a dish that combines spinach with other FODMAP-containing ingredients, the overall FODMAP load of the dish matters. Spinach itself will not push you over the threshold, but it is part of the total picture. An app like FODMAPSnap can help you evaluate the full FODMAP profile of a meal rather than looking at individual ingredients in isolation.
Spinach Compared to Other Leafy Greens
How does spinach stack up against other greens on the FODMAP spectrum?
- Lettuce (all varieties): Low FODMAP. Iceberg, romaine, butter lettuce — all safe in generous amounts.
- Kale: Generally considered low FODMAP, though Monash testing is limited. Safe in typical serving sizes.
- Swiss chard: Low FODMAP in moderate portions.
- Arugula (rocket): Low FODMAP and adds a peppery kick to salads.
- Cabbage: Low FODMAP at about 75g (roughly 1 cup), but may cause gas due to raffinose content (not technically a FODMAP but similarly fermentable).
- Beet greens: Limited FODMAP data; use cautiously.
Spinach stands out for its nutrient density — it packs more iron, folate, and vitamins per serving than most other leafy greens.
Nutritional Spotlight
Spinach is nutritionally exceptional, which matters on a low-FODMAP diet where food variety can be limited.
- Iron: Spinach is a good plant-based iron source (2.7mg per 100g raw). Pair with vitamin C (lemon juice, bell peppers) to enhance absorption.
- Folate: Critical for cell division and particularly important during pregnancy.
- Vitamin A: From beta-carotene. Important for vision, immune function, and skin health.
- Vitamin K: Essential for blood clotting. One cup of raw spinach provides over 100% of the daily value.
- Magnesium: Supports muscle and nerve function. Many IBS patients are low in magnesium.
- Antioxidants: Including lutein, zeaxanthin, and quercetin.
Reintroduction Considerations
Spinach does not require formal FODMAP reintroduction because it is already low FODMAP. You can enjoy it throughout all phases of the diet.
If you experience discomfort after eating spinach, consider whether the issue might be related to oxalates (which spinach contains in relatively high amounts), fiber content, or other ingredients in the dish. Cooking spinach reduces oxalate content somewhat and may improve digestibility.
People taking blood thinners (warfarin/Coumadin) should maintain consistent spinach intake rather than dramatically increasing or decreasing it, as vitamin K affects blood clotting.
Key Takeaways
- Spinach is low FODMAP at 75g (about 2-3 cups raw or 1/2 cup cooked)
- Baby spinach, mature spinach, and frozen spinach are all safe
- Be mindful of the raw-to-cooked volume reduction — cooked spinach is more concentrated
- Spinach is extremely nutrient-dense, providing iron, folate, and vitamins A and K
- It works in salads, smoothies, cooked dishes, and baking
- No reintroduction is required — enjoy throughout all diet phases
Related Reading
- Are Carrots Low FODMAP? — Another reliable low-FODMAP vegetable
- Are Peppers Low FODMAP? — Pair peppers with spinach for colorful salads
- Are Eggs Low FODMAP? — Spinach and eggs make a perfect low-FODMAP breakfast
- Is Oatmeal Low FODMAP? — Try savory oats topped with sauteed spinach
This article is for informational purposes only and does not constitute medical advice. Always consult with a qualified healthcare professional or registered dietitian before making significant changes to your diet, especially if you have IBS, SIBO, or other gastrointestinal conditions. FODMAP tolerance varies between individuals, and a supervised elimination and reintroduction process is recommended for best results.
Track Your Personal FODMAP Triggers
Everyone's gut is different. FODMAPSnap uses AI to analyze your meals for FODMAP content and learns your unique sensitivities over time — so you can eat with confidence.
Frequently Asked Questions
How much spinach can I eat on a low-FODMAP diet?
Baby spinach is low FODMAP at a generous serving of about 75g (roughly 2-3 cups raw). Cooked spinach reduces dramatically in volume — a large handful of raw spinach cooks down to just a few tablespoons. This is important because you might inadvertently eat the equivalent of several raw servings when eating cooked spinach. Stick to about half a cup of cooked spinach per sitting.
Is frozen spinach low FODMAP?
Yes, frozen spinach is low FODMAP. Freezing does not change the FODMAP content of spinach. Frozen spinach is already blanched and compressed, so a small block represents a much larger volume of fresh spinach. A half-cup serving of thawed, drained frozen spinach (about 75-80g) is considered safe.
Is spinach better than kale for a low-FODMAP diet?
Both spinach and kale are low FODMAP. Kale has not been extensively tested by Monash University, but it is generally considered safe in typical serving sizes. Spinach tends to be milder in flavor and more versatile in cooking. Choose based on your taste preference and how your body responds.
Can spinach cause digestive issues despite being low FODMAP?
Spinach is high in oxalates and contains some insoluble fiber, both of which can occasionally cause mild digestive discomfort in sensitive individuals. This is unrelated to FODMAPs. If raw spinach bothers you, cooking it breaks down some oxalates and makes the fiber easier to digest. People with a history of kidney stones should consult their doctor about oxalate intake.