Remedy Routes
    Digestive
    Strong Evidence

    Constipation Relief

    Improved bowel regularity and stool passage.

    TL;DR

    Magnesium and psyllium are the two interventions with the clearest human evidence, working by different routes — osmotic water retention versus stool bulking. Probiotics help some people modestly; stimulant laxatives should stay short-term.

    Why It Matters

    Chronic constipation drives haemorrhoids, anal fissures, and diverticular disease, and in older adults contributes to faecal impaction. New-onset constipation with weight loss or bleeding requires investigation, not supplements.

    How to Measure

    Biomarkers

    Bristol stool scale
    Weekly bowel movement frequency
    Dietary fibre intake

    Optimization Protocol

    Target 25-35 g fibre and 2 L fluid daily, plus a consistent post-breakfast toilet window. Add psyllium 5-10 g daily titrated up slowly, or magnesium citrate/oxide 200-400 mg at night. Reserve stimulant laxatives for rescue use only.

    Supporting Supplements

    Magnesium

    Mineral
    Strong yes
    Strong Evidence
    Effectiveness 4/5

    Magnesium is a reliable, fast-acting option for constipation and works within a day for most people.

    Probiotics

    Probiotic
    Likely effective
    Moderate Evidence
    Effectiveness 3/5

    Specific Bifidobacterium strains modestly increase stool frequency, adding roughly one bowel movement per week.

    L-Glutamine

    Amino Acid
    Insufficient evidence
    Limited
    Effectiveness 1/5

    Glutamine is used for intestinal barrier support, not motility, and has no meaningful constipation evidence.

    Supporting Research

    Frequently Asked Questions

    Which fibre works best?
    Psyllium at 5-10 g/day has the strongest evidence for softening stool and improving frequency. Insoluble bran can worsen bloating in IBS-predominant constipation.
    How much water is needed with fibre?
    Fibre needs fluid to work - roughly 250 mL per dose of psyllium, alongside normal daily intake. Increasing fibre without fluid commonly makes things worse.
    Does magnesium help?
    Magnesium citrate or oxide draws water into the bowel and works within 6-12 hours at around 200-400 mg. It is not for long-term daily use, and should be avoided in kidney impairment.
    Do probiotics help constipation?
    Effects are strain-specific and modest. Bifidobacterium lactis strains have the most supporting data for improving stool frequency, typically over 4 weeks.
    How long should I try something before switching?
    Give fibre 2-4 weeks, increasing the dose slowly to limit bloating. Osmotic agents act within days, so a lack of response there is quicker to judge.
    When does constipation need medical review?
    New constipation after age 50, blood in stool, unexplained weight loss, persistent abdominal pain, or a sudden change in bowel habit all warrant assessment rather than self-treatment.

    Typical Timeframe

    1-3 days for magnesium; 1-2 weeks for fibre

    Research Summary

    Studies9
    Supplements3
    Evidence
    Strong Evidence

    My Notes

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    This information is for educational purposes only. Always consult a healthcare professional before starting any supplement regimen.