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Limited evidenceGut health

Chia Seed

A good source of fiber and ALA that gels in water. Meta-analyses of randomized trials find little to no effect on weight, blood sugar or blood pressure, and its use for regularity rests on fiber content rather than on trials.

Evidence last reviewed: August 2026

What the science says

  • Cardiometabolic outcomes Limited evidence

    A systematic review and meta-analysis of clinical trials of chia found no convincing effect on body weight, blood pressure or lipids, with small and heterogeneous studies. A later GRADE-assessed dose-response meta-analysis reached similar conclusions, with at best marginal changes.

  • Glycemic control Limited evidence

    Meta-analyses report small and inconsistent reductions in fasting glucose and HbA1c, graded as low-certainty evidence.

  • Bowel regularity Limited evidence

    Chia's mucilage holds water and behaves like other gel-forming fibers, but no randomized trial has tested chia seed for constipation or stool form as a primary outcome.

Dosage & safety

Studied doseTrials mostly used 25–35 g per day (about 2–3 tablespoons), soaked or milled. Soaking before eating is sensible.
SafetySafe as a food. Dry seeds swallowed with too little liquid can swell and cause esophageal obstruction — always hydrate them. Gas and bloating at higher intakes; may add to the effect of blood-pressure and anticoagulant medication.

Scientific references

Where to buy

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