Chia Seeds vs. Flax Seeds: Is One Healthier Than the Other?

Chia seeds are little oval-shaped seeds originating from the Salvia hispanica plant, more commonly known as the chia plant. They are sometimes called salba seeds, are usually bought whole, and come in black and white varieties.

Chia seeds are native to Mexico and Guatemala and were likely used as a staple food in ancient Aztec and Mayan diets.

In comparison, flax seeds are flatter and slightly bigger than chia seeds. Also known as linseeds, they are generally brown or golden, can be bought whole or ground, and are thought to originate from the Middle East.

Chia seeds taste pretty bland, whereas flax seeds have a slightly nuttier flavor. However, both types of seeds are easy to incorporate into a variety of dishes.

Both chia and flax seeds are rich in a variety of nutrients.

This table compares flax seeds and chia seeds, listing the amounts of major nutrients per 1-ounce (28-gram) portion, or around 4 tablespoons.

Both seeds contain a good amount of protein and omega-3 fats, with flax seeds containing slightly more.

Flax seeds also have significantly more copper and thiamine.

Chia seeds have slightly fewer calories and more fiber. They also have nearly 2.5 times more of the bone-strengthening mineral calcium, as well as slightly more iron and phosphorus.

Both chia and flax seeds contain good amounts of alpha-linolenic acid (ALA), a type of plant-based omega-3 fat.

ALA is considered essential because it’s a type of fat your body cannot produce. This means you can only get it through your diet. Several studies conclude ALA may lower the risk of heart disease.

Eating chia seeds and flax seeds regularly may help improve cardiovascular health by reducing:

• blood pressure levels
• low-density lipoprotein (LDL) cholesterol levels
• oxidative stress

Because of their high omega-3 content, both flax and chia may reduce blood clotting and thin the blood. People who take blood thinners should consult a healthcare professional before adding large amounts of these seeds to their diets.

Both chia seeds and flax seeds may help reduce risks associated with developing metabolic syndrome and type 2 diabetes.

Both seeds contain good amounts of fiber, which has also been linked to a lower risk of developing type 2 diabetes. Fiber helps prevent type 2 diabetes by slowing down the digestion of carbs and the absorption of sugar into the blood. This leads to a more gradual rise in blood sugar levels after a meal and prevents blood sugar spikes.

This stabilizes blood sugar levels and offers some protection against type 2 diabetes.

Both chia and flax seeds may help protect you against cancer in several ways.

For starters, they’re both rich in fiber, a nutrient generally linked to a lower risk of certain types of cancer.

According to a 2023 review, a diet high in dietary fiber may reduce the risk of the following cancers:

• esophageal
• gastric
• colon
• rectal
• breast
• endometrial
• ovarian
• renal cell
• prostate
• pancreatic

Both seeds also contain antioxidants, which help your body reduce its levels of free radicals. Free radicals are cell-damaging molecules that can contribute to aging and diseases such as cancer.

However, when it comes to antioxidant levels, flax seeds may have the upper hand. That’s because they are the largest source of lignans, a specific type of cancer-fighting antioxidant.

For this reason, flax seeds may be slightly more effective than chia seeds at preventing cancer development.

A 2019 review of research suggests that eating flax seeds regularly may have anticancer effects against certain cancers, including breast cancer and acute myeloid leukemia (AML).

Fewer studies have looked at the effects of chia seeds on the risk of cancer. But chia seeds’ antioxidant and polypherol content may also reduce cancer risk.

However, more studies are needed before conclusions can be made on which is more effective.

Both chia and flax seeds provide multiple antioxidants with cancer-fighting properties.

Chia seeds and flax seeds are both great sources of fiber, which can help reduce hunger and cravings. However, they contain different levels of soluble fiber, a type particularly effective at reducing hunger and controlling appetite.

Soluble fiber tends to become sticky when mixed with water, slowing down digestion and increasing feelings of fullness.

This type of fiber also triggers hormones involved in controlling hunger, which may further reduce appetite.

About 25% of the fiber from flax is soluble. In contrast, only 7–15% of the total fiber in chia is soluble. For this reason, flax seeds may be slightly more effective at reducing hunger and appetite than chia seeds.

Overall, both flax seeds and chia seeds seem to reduce hunger and appetite. However, because of their higher soluble fiber content, flax seeds may be slightly more effective at doing so.

However, more studies directly comparing the two are needed.

Digestion is a critical function your body performs every day, helping you break down the foods you eat and absorb their nutrients.

Poor digestion can make it more difficult for your body to get all the nutrients it needs and can produce some unpleasant side effects.

Flax and chia seeds, due to their high fiber content, may help relieve constipation and diarrhea.

Fiber helps remove buildup from the digestive tract. While soluble fiber may slow digestion, insoluble fiber adds bulk to your stool and may speed up the passage of food through your gut.

Insoluble fiber in both flax and chia seeds can act as a mild laxative, which may help reduce constipation.

The gel-forming properties of soluble fiber, which is found in higher amounts in flax seeds, can help digestive waste bind together, reducing diarrhea.

Both flax and chia seeds are incredibly versatile and very easy to add to your diet. Both taste relatively bland, so you can add them to almost anything.

Whole

You can sprinkle them on top of yogurts or incorporate them into smoothies, oatmeal, or baked goods. Both can also be used to thicken sauces or as egg substitutes in many recipes.

Regarding how much to eat, most of the benefits listed above were seen with 1–2 tablespoons (10–20 grams) of seeds per day.

Ground

While both types can be consumed whole, there are advantages to consuming them ground.

Whole flax seeds can go through your gut without being absorbed, because their outer shells are hard for your intestines to break down. Eating them ground can help increase the absorption of the nutrients they contain.

Chia seeds are often consumed whole. However, research suggests that the nutrients they contain may also be better absorbed when the seeds are ground.

Because of their high fat content, both types of seeds should be stored in the refrigerator or freezer to prevent them from going rancid. For the same reason, make sure to consume them promptly.

Chia and flax seeds are very nutritious and offer similar benefits for heart health, blood sugar levels, and digestion.

However, flax seeds appear to have a slight advantage, especially when it comes to reducing hunger and appetite and lowering the risk of certain cancers. Plus, they’re often less expensive.

Ultimately, the differences between the two seeds remain small. Either flax seeds or chia seeds, or both, would be a great addition to your diet.