Do Chia Seeds Have Side Effects?

Chia Seeds are a Good Source of Fiber and Omega-3 Fatty Acids

Mason jar of chia pudding with sliced bananas
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Chia seeds may be tiny, but they offer big nutrition in the form of omega-3 fatty acids and dietary fiber. Are there any side effects to eating chia seeds?

Clues to whether chia seeds have any adverse side effects can be gathered from some randomized controlled trials investigating the seeds' ability to boost energy or weight loss.

Studies on Chia Seeds

Lead author of two such trials, Director of Appalachian State University's Human Performance Laboratory David Nieman, says subjects in one experiment were given 6 tbsp (50 g) of ground or whole chia seeds in water daily — in two 25 g doses on an empty stomach.

During the 12-week study period, participants were surveyed about hunger and energy levels, and also for symptoms of digestive distress such as heartburn, constipation, bloating, nausea or diarrhea.

Despite the fact the experimental dose of chia seeds constituted almost 19 grams of extra fiber each day, Nieman's team writes that the subjects did not suffer digestive problems whether they got chia seeds as a supplement, or a placebo made up of ground or whole poppy seeds.

The 2009 study, published in Nutrition Research, examined whether consuming 50 grams of chia seeds each day would result in significant weight loss. It didn't.

According to Wayne Coates, professor and author of Chia: The Complete Guide to the Ultimate Superfood writes that cramping might result from eating a large volume of chia seeds, because the seeds absorb water from the stomach during digestion. He recommends increasing your water intake to offset this reaction.

What About Healthy Side Effects?

A beneficial side effect of adding chia seeds to your diet is that they might help improve blood levels of certain healthy fatty acids, as suggested in one of Nieman's studies, an investigation published in 2012 in the Journal of Alternative and Complementary Medicine.

Among 62 overweight but otherwise healthy post-menopausal women, those consuming 25 grams of ground chia seeds daily did have increased levels of alpha-linolenic acid (ALA) and eicosapentaenoic acid (EPA) in their blood. Broader disease markers, however (such as blood pressure or inflammation) did not differ between those consuming ground, whole, or no chia seeds at all.

Bottom line?

Chia seeds remain a healthy source of fiber and omega-3 fatty acids​, and may help you lose weight because they absorb water, and water within food has been shown to satisfy longer than water consumed with a meal. You can likely feel free to add chia seeds to your anti-aging breakfast or green smoothie, without fear of digestive problems later. However, if they do cause gas or intestinal bloating, scale back on the amount you eat each day, try increasing your water intake, and let your body adjust to the increased fiber more gradually.

Related Articles:


Coates, Wayne. Chia: The Complete Guide to the Ultimate Superfood. Sterling Publishing. 2012.

David Nieman, Director of Human Performance Laboratory, Appalachian State University. Interview conducted April 30, 2013.

Nieman DC, Cayea EJ, Austin MD, Henson DA, McAnulty SR, Jin F. "Chia seed does not promote weight loss or alter disease risk factors in overweight adults." ​Nutr Res. 2009 Jun;29(6):414-8

Nieman DC, Gillitt N, Jin F, Henson DA, Kennerly K, Shanely RA, Ore B, Su M, Schwartz S. "Chia seed supplementation and disease risk factors in overweight women: a metabolomics investigation." J Altern Complement Med. 2012 Jul;18(7):700-8.

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