Vitamins and IBS? An IBS Diet Quick Tip!

  • Vitamin and mineral supplements can cause IBS upsets.

    • Ask your pharmacist for the most tolerable brands of vitamins in their store.

    • Prenatal vitamins may be an option - they're often formulated to minimize GI side effects.

      • This is NOT an option for men, who should never take vitamins with iron unless their doctor approves.

    • Chewable vitamins are sometimes easier on the tummy.

    • Ask your doctor about liquid vitamins or vitamin shots if you can't tolerate pills.

  • Watch out for fillers and additives in vitamins - avoid lactose, artificial colors, artificial sweeteners, inulin, FOS, GOS, MOS, "oligosaccharides" and preservatives.

    • Health food stores may have a wider variety of additive-free vitamins than drug stores.

  • Try two or three smaller-dose vitamin/mineral supplements daily instead of one large dose.

    • This reduces the risk of GI upsets, and aids your body in absorbing the nutrients. Can't find smaller-dose vitamins? Try breaking a regular pill in half.

  • Never take vitamin pills on an empty stomach!

    • Take with a high soluble fiber, low fat meal. For extra GI stability add a dose of your Tummy Fiber to the meal as well.

  • There is new evidence that Vitamin D may help IBS.

    • Low Vitamin D levels may be linked to IBS. Your doctor can check your Vitamin D levels.

    • Supplementation with Vitamin D may help IBS pain, bloating and gas.

  • Vitamin C is notorious for causing gas, abdominal cramps, and diarrhea.

    • The recommended dose for Vitamin C is generally under 2,000 mg. daily. Over that, and you really risk GI side effects. Unless your doctor has recommended otherwise, don't exceed one hundred percent of the US RDA for Vitamin C.

    • A buffered form of vitamin C such such as calcium ascorbate (trademark Ester-C), sodium ascorbate, or magnesium and/or zinc ascorbate may be easier on the gut and more tolerable for IBS as the acidity of the vitamin is buffered, or neutralised, by chemically combining it with the mineral.

  • Thiamine, or Vitamin B1, aids digestion. When your thiamine levels are low, your digestion may slow, which can lead to constipation.

  • Calcium is constipating, which can be helpful or hurtful depending on your symptoms. Magnesium is a laxative, and this too can help or hurt, depending.

    • If you alternate between IBS diarrhea and constipation, try a supplement with a balance of calcium and magnesium.

    • If you're prone to diarrhea, try calcium carbonate, which has no magnesium.

    • If you're prone to constipation, try calcium citrate or cal-mag, which contains magnesium.

    • With either form of calcium, there should be Vitamin D included for the best possible absorption.

    • In general, take only 500 mg. of calcium per dose, as your body may not be able to absorb more than this all at once.

  • Iron can cause stomach upsets. Iron blocks the absorption of calcium. If you aren't anemic or prone to anemia, ask your doc if you need an iron supplement at all.

    • Iron in the form of ferrous sulfate can cause constipation.

    • Iron as ferrous gluconate should be non-constipating.

    • Iron is best absorbed in the presence of Vitamin C.

    • Juggling different supplements? Try a multivitamin with C and iron at one meal, and calcium or calcium/magnesium combination with Vitamin D at another meal.

  • It's best to get vitamins and minerals from a wide variety of fresh fruits, vegetables, legumes, grains, and nuts. There are many nutrients in whole foods that can't be extracted into pills.

  • Struggling to get nutrients and keep your IBS stable? Check Eating for IBS for nutritious IBS-safe diet guidelines and recipes.

Tip Takeaway: Vitamin and mineral supplements often cause IBS upsets. Always take these supplements with meals, in the lowest dose possible for your needs.

See all IBS Quick Tips!


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