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Psyllium Husk (fiber)

A soluble, gel-forming fiber. One of the best-proven supplements: lowers LDL cholesterol and improves constipation, with decades of consistent trials.

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What the science says

  • Lowering LDL cholesterol Strong evidence

    Meta-analyses of randomized trials show that ~10 g/day of psyllium lowers LDL cholesterol by roughly 5–10%, an effect recognized by regulators in approved heart-health claims.

  • Relieving constipation Strong evidence

    As a gel-forming bulk laxative, psyllium consistently improves stool frequency and consistency in chronic constipation, and is a first-line recommendation in clinical guidelines.

  • Blood sugar and satiety Moderate evidence

    Taken before meals, psyllium modestly improves post-meal glucose in people with type 2 diabetes and can increase satiety.

Dosage & safety

Studied dose5–10 g/day, split with meals, mixed in plenty of water. Start low to minimize bloating.
SafetyVery safe. Must be taken with adequate water. Separate from medications by 1–2 hours as fiber can reduce their absorption.

How to take it

TimingSplit across the day with meals — that is how the cholesterol and glucose studies dosed it.
With food?With meals, and always with a full large glass of water — psyllium taken with too little liquid can swell and obstruct the throat or gut.
Worth knowingBuild up over 1-2 weeks; the gas and bloating that make most people quit in the first few days usually settle.

Interactions

With medications

  • all oral medications

    Fiber traps drugs in the gut and delays or reduces their absorption — this applies broadly, not to any single class. take medication at least 1 hour before or 2-4 hours after psyllium

  • levothyroxine, digoxin, lithium and carbamazepine

    These have narrow therapeutic ranges, so even a modest absorption change matters. separate by at least 4 hours and keep your routine consistent

  • insulin and other antidiabetic drugs

    Psyllium slows carbohydrate absorption and lowers post-meal glucose, which can add to medication. monitor blood glucose when starting; doses may need adjusting

With other supplements

  • iron, zinc and calcium

    Fiber binds minerals taken at the same time and reduces absorption. take minerals at a different meal

Well-established interactions only — this is not a complete list. Always tell your doctor and pharmacist what you take.

Frequently asked questions

Does psyllium lower cholesterol?

Yes — the evidence is strong. Meta-analyses of randomized trials show about 10 g/day of psyllium lowers LDL cholesterol by roughly 5–10%, an effect regulators recognize in approved heart-health claims.

Does psyllium work for constipation?

Yes, with strong evidence. As a gel-forming bulk laxative, psyllium consistently improves stool frequency and consistency, and clinical guidelines list it as a first-line option.

How should I take psyllium husk?

Take 5–10 g/day of psyllium split across meals, always with a full large glass of water, since too little liquid can let psyllium swell and obstruct the throat or gut. Build up over 1–2 weeks to limit gas and bloating.

Is psyllium safe to take with medications?

Separate them: take medication at least 1 hour before or 2–4 hours after psyllium, because fiber reduces drug absorption. For narrow-range drugs like levothyroxine or lithium, keep psyllium at least 4 hours apart.

Scientific references

Where to buy

Nutricost, Psyllium Husk, Whole Husk, Unflavored, 8.1 oz (227 g)

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