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Back in the 80s and 90s, flaxseeds were mostly found in hippie households, and chia seeds were best known for their role in the popular Chia Pet that sprouts chia to resemble an animal’s fur.
Nowadays, chia and flaxseeds are well-known for their superfood-status nutritional qualities that provide myriad health benefits.
But which seed is supreme?
In this article, we’ll look at the differences between chia seeds and flaxseeds, from nutrition to health benefits to taste, to see which one is in the top-seeded position.
Both chia and flaxseeds are nutritional powerhouses that pack a fiber and protein punch in their tiny packages.
Chia seeds—sometimes referred to as Salba—are small, round black or white seeds that originate from the Salvia hispanica plant and are native to Mexico and Guatemala.
In these two countries of origin, chia seeds were a staple food consumed by the Aztecs and Mayans.
Chia means “strength” in the Mayan language, where these little seeds were used to fuel ancient Aztec and Mayan warriors on their long days of battle.
Conversely, flaxseeds—sometimes called linseeds—are bigger than chia seeds, typically golden brown, and originated from the Middle East, Egypt, and India.
Flaxseeds have also been revered for their nutritional quality for millennia—as far back as the 8th century, King Charlemagne believed so strongly in the power of flaxseeds that he passed laws requiring their consumption.
As far as their culinary use goes, chia seeds are often eaten whole and are mild in flavor, while flaxseeds have a nutty flavor and are more commonly consumed in a ground-up form—especially in baked goods.
Compared to flaxseeds, chia seeds are easier to digest in their whole form—especially when soaked in liquids.
Because of their low digestibility, many people consume ground flaxseeds instead of whole.
Both seeds are gluten-free, vegan, and often consumed on low-carb diets due to their low amounts of net carbs.
Both chia and flaxseeds are rich in fiber, protein, vitamins, and minerals.
They also both contain high amounts of alpha-linolenic acid (ALA), a plant-based omega-3 fat that is linked to anti-inflammatory effects and a reduced risk of chronic conditions like heart disease, obesity, neurodegenerative diseases, and stroke.
But, the two seeds do have some striking differences, especially when it comes to fiber, niacin, and calcium content—let’s take a closer look.
|Chia Seeds (1 oz serving; about 2.5 Tbsp)||Flaxseeds (1 oz; about 3 Tbsp)|
|Total Fat||9 g||11.8 g|
|Saturated fat||0.9 g||1.1 g|
|Unsaturated Fat||8.1 g||10.7 g|
|Carbohydrates||12 g||8.3 g|
|Protein||4.7 g||5.2 g|
|Phosphorus||11% of the Daily Value (DV)*||15% of the DV|
|Niacin||16% of the DV||5% of the DV|
|Iron||12% of the DV||9% of the DV|
|Calcium||17% of the DV||7% of the DV|
|Magnesium||23% of the DV||27% of the DV|
|Alpha-linoleic acid (omega-3 fat)||4900 mg||6000 mg|
*Daily Value percentages may differ between men and women and older and younger adults.
As you can see, chia seeds contain fewer calories, total fat, unsaturated fat, protein, phosphorus, magnesium, and ALA than flaxseeds.
Conversely, chia seeds are slightly higher in fiber, niacin, iron, and calcium than flax.
Both chia and flaxseeds have been studied for their role in various health outcomes, which are mainly due to their high levels of antioxidants, omega-3 fatty acids, and micronutrients.
The primary antioxidants in chia seeds are chlorogenic acid and caffeic acid—which are also found in coffee—as well as quercetin, myricetin, and kaempferol, found in fruits and veggies like apples, onions, tomatoes, spinach, and kale.
These antioxidants are linked to reduced inflammation and oxidative stress—the accumulation of molecules called free radicals or reactive oxygen species that damage our cells.
Flaxseeds are also rich in antioxidants, including hydroxycinnamic acids (ferulic acid and p-coumaric acid), lignans, and phytosterols.
Hydroxycinnamic acids provide anti-inflammatory and antimicrobial effects, while lignans are known as phytoestrogens.
Phytoestrogens are plant-based compounds that mimic estrogen in the body and bind to estrogen receptors, which may help reduce the growth of estrogen-related cancers, like breast, ovarian, and endometrial; however, future research on the dose and types of phytoestrogens is ongoing.
Flaxseed also contains phytosterols, which are plant forms of cholesterol that may help to lower “bad” cholesterol levels by competing for its absorption in the body.
Both chia seeds and flaxseeds have been studied for their role in reducing the risk of cardiovascular diseases, likely due to their high levels of omega-3 fatty acids, fiber, and antioxidants.
Risk factors for heart disease include poor blood sugar control, dysregulated cholesterol and lipid levels, and high markers of inflammation.
Research has shown that chia seeds increase blood levels of HDL (“good”) cholesterol and reduce triglyceride, blood pressure, and blood sugar levels, which may translate to better heart health.
Flaxseeds show similar benefits, with studies finding flaxseed consumption to be linked to decreased atherosclerosis—the buildup of plaque in the arteries that obstructs blood flow—and lower blood pressure, blood sugar, and inflammation.
For example, one study of people with type 2 diabetes found that those who consumed 10g of flaxseed powder per day for one month had reductions in their fasting blood sugar, LDL cholesterol, and triglycerides by 20%, 22%, and 17.5%, respectively.
The high fiber content in chia and flaxseeds may lend itself to weight loss or a healthier body weight.
Chia seeds have slightly more fiber than flaxseeds, but flax has more soluble fiber.
Soluble fiber is especially beneficial for reducing hunger hormones, which control appetite and increase satiety—and about 33% of the fiber in flaxseeds is soluble, while only up to 15% of the fiber in chia seeds is soluble.
Therefore, flaxseeds may be slightly more effective at controlling appetite than chia, which could translate to healthier body weights.
One small study gave people bread containing different amounts of chia seeds, finding that the most chia seed-dense bread reduced appetite up to two times faster than those with lower amounts of chia.
Another study found that people who consumed chia seeds alongside a calorie-restricted diet for six months experienced significantly more weight loss and reduced waist circumference than people on the calorie-restricted diet alone.
However, another concluded that there was no difference in weight loss in overweight and obese people who consumed chia seeds compared to those who did not.
Research with flaxseed has also shown some beneficial results.
A meta-analysis of 45 randomized controlled trials found that flaxseed consumption significantly reduced body weight and waist circumference, especially in longer-term interventions over 12 weeks and in overweight or obese people.
Consumption of chia seeds or flaxseeds may reduce the risk of certain cancers because they are high in fiber and antioxidants—especially the lignans in flaxseed.
In a systematic review of human trials, consuming 25g of ground flaxseed (about 3 tablespoons) per day exhibited significant protective effects against breast cancer as well as reducing tumor size and risk of mortality in women with breast cancer.
Another study of over 6,000 women found that regular consumption of flaxseed reduced the risk of developing breast cancer by up to 18%.
There have been fewer studies on the effects of chia consumption and cancer, but a high intake of insoluble fiber—found in both chia and flax—is also linked to a reduced risk of cancers, particularly colon or colorectal cancer.
However, more studies are needed before it can be said definitively that eating chia or flaxseeds will prevent or slow the progression of cancer.
Both chia and flaxseed can be beneficial for weight loss due to their high fiber content.
Chia may be more effective because it contains a bit more fiber than flaxseed.
Chia seeds also expand in liquids—you’ll notice this if you’ve ever made chia pudding or added chia to water—which means they also expand in your stomach, increasing feelings of fullness.
However, flax contains more soluble fiber, which silences hunger hormones and increases satiety after eating.
Overall, eating chia seeds or flaxseeds can be beneficial for health and may induce modest weight loss.
Yes, you can eat flaxseeds and chia seeds together.
This is beneficial because you can increase the range and variety of nutrients you consume while bolstering your fiber and omega-3 intake.
Although rare, some people can have allergic reactions to chia seeds and should not consume them.
People with allergies to mint, sesame, or mustard seeds should also be cautious about eating chia seeds because chia is in the mint family and can have cross-reactivity with sesame or mustard seeds.
You don’t have to soak chia seeds before consumption, but soaking can increase the availability of nutrients and make them easier to digest.
Chia seeds can absorb up to 12 times their weight in water, so soaking them or adding them to another liquid—like into a smoothie, for example—is the best way to consume them.
Plus, eating large amounts of raw chia seeds can actually be dangerous because they expand in your digestive tract and can create blockages.
A way to bypass this danger is by ensuring you consume adequate amounts of water while eating whole, unsoaked chia seeds.
A typical serving size of chia seeds is 1 ounce, which translates to about 2.5 tablespoons.
However, you could eat more chia seeds if you want—just not too many, as excessive chia seed intake can cause digestive problems like bloating, constipation, or diarrhea.
Like chia seeds, you can overdo it on flaxseeds because the high fiber content can cause digestive issues.
While you can consume whole flaxseed, grinding them increases nutrient availability and enhances their health benefits.
If you don’t grind them, many people can’t digest the seeds, and they will pass through the body.
It’s best to purchase whole flaxseeds and grind them at home before use with a small spice or coffee bean grinder.
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