Which is better, chia seeds or flax seeds?

They win different columns. Chia has 34.4g of fiber per 100g against 27.3g for flax, and 631mg of calcium per 100g against 255mg. Flax has 18.3g of protein per 100g against 16.5g, and a lower carbohydrate total at 28.9g of carbs per 100g against 42.1g. Calories follow the fat, 486 calories per 100g for chia and 534 for flax. Keeping both jars costs nothing and covers everything.

Which has more fiber, chia seeds or flax seeds?

Chia, and the gap is wide. Our data lists 34.4g of fiber per 100g for chia against 27.3g for flax, a difference of 7.1g of fiber per 100g. Spoon for spoon it widens again, because a chia tablespoon weighs 12g and a flax tablespoon only 10g: 4.1g of fiber from chia against 2.7g from flax. Roughly 82% of chia's carbohydrate is fiber, which is what lets it gel in water.

Do you have to grind chia seeds like flax seeds?

No. Flax has a hard hull that mostly passes through intact, so grinding is what releases the 18.3g of protein per 100g and the ALA fats behind it. Chia does the opposite and absorbs water, turning a 12g tablespoon into a gel that still counts as 58 calories. Grind flax fresh and keep it cold, because 42.2g of fat per 100g turns rancid faster than most people expect.

Which has more omega-3, chia or flax?

Flax is the stronger ALA source and chia is not far behind. Our data breaks the fat out only for chia, which carries 23.7g of polyunsaturated fat per 100g, the fraction ALA sits inside. Flax carries more fat overall, 42.2g of fat per 100g against 30.7g for chia. Conversion of ALA into EPA and DHA is slow in most people, so treat either seed as a supplement to oily fish rather than a replacement.

Which is better for weight loss, chia or flax?

Both are add-ons, not meals, and the calories arrive fast. A 12g chia tablespoon is 58 calories against 55 for a 10g flax tablespoon, and per 100g chia is the lighter of the two at 486 calories per 100g against 534. Chia's fiber swells in liquid, which is a real satiety effect at breakfast. The usual mistake is scale: a quarter cup is 195 calories of chia or 218 of flax, which is no longer a garnish.

Which is better for keto, chia seeds or flax seeds?

Flax, by more than the fiber numbers suggest. It has 1.6g of net carbs per 100g against 7.7g for chia, because it starts lower on total carbohydrate: 28.9g of carbs per 100g against 42.1g. A flax tablespoon is effectively free at about 0.2g net, while a chia tablespoon costs roughly 0.9g. Both work on keto. Flax just leaves more room.

How much chia or flax should you eat per day?

One to two tablespoons of either is the normal range. For chia that is 58 to 116 calories and 4.1 to 8.2g of fiber; for ground flax, 55 to 110 calories and 2.7 to 5.5g. Push much past that and the fiber load stops being pleasant, since chia runs 34.4g of fiber per 100g against 27.3g for flax. Add it over a week or two, and drink more water while you do.

Chia Seeds

Flax Seeds

All Comparisons

Chia Seeds vs Flax Seeds

Chia Seeds

Wins in 4 of 6 categories

Compare chia seeds and flax seeds: fiber, protein, fat, net carbs and calories per 100g and per tablespoon, plus whether you need to grind them first.

Verdict (USDA data)

Per 100g (USDA data), Chia Seeds has 486 calories vs Flax Seeds's 534. Chia Seeds has more fiber (34.4g vs 27.3g); Flax Seeds has more protein (18.3g vs 16.5g). Pick Chia Seeds for more fiber, Flax Seeds for more protein.

Sources: Chia Seeds (FDC 170554) · Flax Seeds (FDC 169414)