Chia Seeds vs. Flax Seeds: Registered Dietitians Crown the Healthier Superfood

Despite their tiny size, seeds pack a nutritional punch. This is especially true of chia seeds and flax seeds—two popular varieties known for their nutty flavor and plant-based protein. The ingredients can also be used in similar ways, but they’re not exactly identical. Ahead, experts explain the nutritional and culinary differences between chia seeds vs. flax seeds, plus which superfood is healthier for you.

What Are Chia Seeds?

Chia seeds are the seeds of the chia plant, which is native to Mexico and Guatemala. The seeds are small, flat, oval-shaped, and come in many colors—including red, white, and black. In the United States, black chia seeds are the most common variety. 

Nutrition

“Chia seeds are an excellent source of fiber, which plays a crucial role in supporting healthy digestion, lowering cholesterol, stabilizing blood sugar levels, and keeping you full after meals,” explains Marissa (Meshulam) Karp, MS, RD, CDN, registered dietitian and founder of MPM Nutrition. The tiny seeds are also packed with antioxidants, which fight free radicals (i.e., harmful molecules). This is noteworthy because high levels of free radicals can increase inflammation and oxidative stress, potentially increasing the risk of chronic disease. What’s more, chia seeds contain bone-supporting calcium, anti-inflammatory omega-3 fatty acids, and satiating plant-based protein.

Flavor and Texture

“Dry chia seeds are crunchy and lightly ‘pop’ when eaten,” says Ann Ziata, chef-instructor at the Institute of Culinary Education in New York City. They’re mildly nutty, and easily take on flavors of other ingredients, especially when soaked. That being said, “soaked chia seeds are loved for their unique texture, as they absorb a lot of liquid and [turn] from crunchy seeds into soft pearls,” Ziata adds.

What Are Flax Seeds?

Native to Turkey and Iran, the flax plant is a shrub that produces edible seeds. These seeds are known as flax seeds or linseed. The seeds are smooth, brown, and shaped like teardrops.

Nutrition

“Like chia seeds, flax seeds are a rich source of fiber and omega-3 fatty acids,” explains Karp. Both nutrients have satiating and anti-inflammatory properties in the body, making flax seeds a worthwhile addition to your rotation. Flax seeds also provide lignans—an antioxidant known for supporting the heart and bones, Karp notes. Additionally, the ingredient provides protein and vitamin E, an essential nutrient with antioxidant effects. 

Flavor and Texture

“Flax seeds have a warm, nutty, earthy, and slightly grassy flavor,” shares Ziata. The taste is similar to sesame seeds mixed with bran, she adds. Whole flax seeds are coarse and fibrous, while ground flax seed has a grainy powdery consistency. However, when ground flax seed is mixed with liquid, it develops a gel-like texture.

How to Eat Chia Seeds

Chia seeds are deliciously versatile, though it’s not recommended to eat them dry. That’s because they can absorb liquid in the body, potentially causing gastrointestinal issues and blockages. With that in mind, chia seeds should always be combined with liquid first.

Most often, chia seeds are used to make chia pudding, a sweet and creamy concoction that can be enjoyed as a breakfast, snack, or dessert. The pudding is easy to make: Mix chia seeds with your preferred milk and flavoring add-ins (think cocoa powder or maple syrup), then store in the refrigerator overnight. “The seeds will absorb the liquid and swell up, creating a tapioca-like pudding,” says Ziata. From there, you can add fruit for a Strawberry-Chia Breakfast Pudding or Apple Cinnamon Chia Pudding. Chia seeds are also a popular ingredient in smoothies, where they’ll add thickness and a nutty flavor. 

In baking, the ingredient can be used as an egg substitute. Simply combine 1 tablespoon of whole chia seeds with 3 tablespoons of water, let sit until a gel forms, then add to your batter as usual. But take note: “Chia seeds will continue to absorb liquid even after baking, so you may wish to use them in recipes with a lot of fat—like fudgy brownies—to prevent the baked goods from drying out,” Ziata advises.

How to Eat Flax Seeds

Flax seeds, whether whole or ground, can be eaten dry. That’s because they don’t swell up and absorb as much liquid as chia seeds, even when ground. Thus, the best uses for flax seeds are slightly different.

“[When whole], flax seeds can be used as an earthy, crunchy topping for breads, muffins, crackers, and salads,” says Ziata. They can also be pressed to make flaxseed oil, which is appreciated for its high nutritional content and powerful nutty flavor. However, flaxseed oil has a low smoke point, meaning it can easily burn at high temperatures. Because of this, it’s best used in raw preparations, like salad dressings or garnishes. 

When ground, flax seeds can be incorporated into cereal, oats, yogurt, smoothies, and condiments for extra texture, notes Ziata. “Additionally, finely ground flax seeds can be used as an egg substitute for baking cookies, cakes, and more,” she adds. For each egg in a recipe, mix one tablespoon of finely ground flax seeds with three tablespoons of warm water, then let sit for several minutes until thick. This will create a gel that can be used to bind ingredients together, just like an egg would. 

Can You Use Chia Seeds Instead of Flax Seeds?

In general, you can use chia seeds in place of flax seeds, but it depends on the recipe and how you’d like to prepare the seeds.

For example, in smoothies, chia seeds and flax seeds can be used interchangeably. “However, flax seeds may add more flavor than chia seeds,” notes Ziata. Meanwhile, in baking, both chia seeds and flax seeds can be used as egg substitutes. Ziata prefers flax seeds because they can bind ingredients without absorbing too much moisture, which is a potential risk with chia seeds.

It’s worth noting that chia seeds and flax seeds aren’t interchangeable when it comes to pudding. When combined with liquid, flax seeds will develop a more grainy and unpleasant texture compared to chia seeds. Flax seeds also have a stronger flavor than chia seeds, making it difficult to add flavor to a pudding with other ingredients. 

Which One Is Healthier?

If you’re stuck between chia seeds vs. flax seeds, there’s “no clear winner” in terms of nutrition, says Karp. “[Both ingredients] offer impressive health benefits, and incorporating either into your daily routine can be a great choice,” she adds. 

Otherwise, a good place to start is your nutritional goals. “If you’re looking for a fiber-rich option to support digestion, chia seeds may be the better choice,” Karp explains. That’s because they deliver more than double the amount of fiber than flax seeds, she notes. “On the other hand, if maximizing antioxidant intake is your priority, flax seeds might be the way to go,” Karp adds. This is due to their rich content of lignans, giving them the edge in the antioxidant department.

Bottom line? “The best foods for your health are the ones that you consistently enjoy and include in your diet,” Karp concludes. So, whether you’re blending a smoothie or garnishing yogurt, it’s worth reaching for chia seeds or flax seeds—or maybe a bit of both!