Which Is Better for Omega-3s and Magnesium?

Chia seeds and flaxseeds may be tiny, but they pack an impressive amount of nutrients: fiber, healthy fats like omega-3s, and even minerals like magnesium. Both seeds have been linked to health benefits like improved blood sugar and lowered cholesterol.

Chia and flaxseeds are both good sources of healthy fats, including alpha-linolenic acid (ALA), a type of omega-3 found in some plant foods. One ounce of flaxseeds provides around 6.4 grams of ALA, while the same serving of chia seeds provides 5 grams.

ALA has anti-inflammatory effects, and increasing dietary intake of ALA is associated with a lower risk of heart disease, including coronary heart disease, the most common heart disease in the United States.

Flaxseeds and chia seeds also provide protective plant compounds, like lignans. These compounds have anti-inflammatory, cholesterol-lowering, and antiatherosclerotic properties—meaning they help prevent plaque buildup in artery walls. Chia seeds contain polyphenols like caffeic acid, ferulic acid, rosmarinic acid, and flavonoids, which protect against cell damage.

One ounce of flaxseeds provides 111 milligrams of magnesium, or about 26% of the recommended daily value. Chia seeds aren’t too far behind—one ounce of those contains 95 milligrams of magnesium.

Magnesium is a powerhouse nutrient for the human body—it’s necessary for more than 300 different chemical reactions needed to sustain life, including:

• Maintaining nerve and muscle function
• Supporting a healthy immune system
• Keeping your heartbeat steady
• Helping bones remain strong
• Stabilizing and adjusting blood glucose levels

Here’s a closer look at how a one-ounce serving of chia seeds and flaxseeds compares for macro and micronutrients.

 
Chia Seeds
Flaxseeds

Calories
138
150

Protein
4.7 grams (g)
5 g

Carbs
11.9 g
8 g

Fiber
9.8 g
8 g

Fat
8.7 g
12 g

Iron
2.2 milligrams (mg), or 12% of the Daily Value (DV)
1.6 mg, or 9% of the DV

Calcium
179 mg, or 14% of the DV
57 mg, or 4.5% of the DV

Copper
0.26 mg, or 29% of the DV
0.35 mg, or 39% of the DV

Magnesium
95 mg, or 23% of the DV
111 mg, or 26% of the DV

Manganese
0.77 mg, or 33.5% of the DV 
0.69 mg, or 30% of the DV

Thiamine
0.18 mg, or 15% of the DV
0.46 mg, or 38% of the DV

Selenium
15.6 micrograms (mcg), or 28% of the DV
7.2 mcg, or 13% of the DV

Zinc
1.3 mg, or 12% of the DV
1.2 mg, or 11% of the DV

Chia seeds contain more fiber than flaxseeds. They provide 9.8 grams of fiber per ounce, while flaxseeds provide 8 grams. However, chia seeds and flaxseeds are composed of different types of fiber. 

• Flaxseeds: 40% fiber by weight—25% soluble fiber and 75% insoluble fiber
• Chia seeds: 30-40% fiber by weight—85–93% insoluble fiber, 7–15% soluble fiber

Soluble fibers dissolve in water and can be fermented or broken down by bacteria in your digestive tract. This helps draw water into poop, keeping it soft and easy to pass. Soluble fiber also reduces cholesterol by blocking its absorption in the digestive tract and helping the body get rid of it.

Insoluble fiber doesn’t dissolve and isn’t fermented well by gut bacteria. Insoluble fiber promotes comfortable and regular bowel movements by adding bulk to your stool. 

Chia seeds and flaxseeds can be added to sweet and savory recipes, but first there’s a key difference to consider:

• Chia seeds absorb liquid and form a gel-like texture. This makes them ideal for thickening smoothies, sauces, and puddings.
• Flaxseeds are best consumed ground. Whole flaxseeds can be tougher on the digestive system, since they may pass through whole.

You can easily add both chia seeds and flaxseeds to meals to increase the fiber and overall nutritional value by:

• Mixing them into yogurt and oatmeal.
• Adding them to smoothies and protein shakes.
• Using them in baked goods like breads, muffins, and crackers.
• Combining chia seeds with milk or nut milk and let the concoction thicken to make chia pudding.
• Using chia seeds to thicken sauces and dressings.
• Adding chia and flaxseeds into homemade granola and energy balls.
• Making chia seed jam by mixing chia seeds with cooked fruit.

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