What type of magnesium doesn't cause stomach issues? A complete guide

November 21, 2025 •

3 min read

An estimated half of Americans may not meet their daily magnesium needs through diet alone, but for many, common supplements can cause digestive upset like cramping and diarrhea. Finding the right form is crucial if you are concerned about what type of magnesium doesn't cause stomach issues.

Quick Summary

This guide examines different magnesium supplement forms, explaining why certain types trigger digestive distress while others are gentle on the stomach. It offers insights into which highly absorbable options, like glycinate and malate, can be tolerated more easily, aiding your supplement choice.

Key Points

Magnesium Glycinate is Safest: As a chelated form, magnesium glycinate is highly absorbable and the least likely to cause digestive upset or diarrhea, making it ideal for sensitive stomachs.
Low Bioavailability Causes Issues: Poorly absorbed forms like magnesium oxide and hydroxide leave excess magnesium in the gut, which draws water into the bowels and acts as a laxative.
Magnesium Malate is Another Good Option: For those seeking energy support with minimal digestive impact, magnesium malate is a well-tolerated and highly bioavailable form.
Avoid Citrate and Oxide for Stomach Comfort: Magnesium citrate is often used for constipation and magnesium oxide has very low absorption, so both are more prone to causing stomach issues compared to chelated forms.
Start Slow with Dosage: To minimize the risk of any digestive side effects, start with a lower dose of any magnesium supplement and increase it gradually.
Consider Your Primary Goal: The best magnesium for you depends on your health objective; choose glycinate for relaxation and sleep, malate for energy, or citrate only if you need a laxative effect.

Why Some Magnesium Causes Stomach Issues

Many people experience uncomfortable side effects like bloating, cramping, and diarrhea when taking magnesium supplements. This is often due to the form of the supplement and how well the body can absorb it.

Less absorbable forms, such as magnesium oxide and high doses of magnesium citrate, remain in the digestive tract in higher amounts. These unabsorbed magnesium salts draw water into the intestines, which softens stools and stimulates bowel movements, leading to potential digestive upset.

Forms of magnesium that are highly bioavailable are absorbed more completely in the small intestine, resulting in less unabsorbed mineral to cause irritation in the gut. Choosing a chelated or bonded form of magnesium is therefore important for those with sensitive digestive systems.

Gentle Magnesium Forms That Minimize Discomfort

For those seeking magnesium's benefits without gastrointestinal side effects, certain forms are known for being gentle and having high absorption rates.

Magnesium Glycinate

Magnesium glycinate is a chelated form where magnesium is bound to the amino acid glycine. This form is well-regarded for its high bioavailability and is less likely to cause digestive issues than other types. Glycine also has a calming effect, making this form popular for relaxation and sleep support.

Magnesium Malate

Combining magnesium with malic acid, magnesium malate is another well-tolerated form with good absorption. Malic acid is involved in energy production, so this form is often favored by those looking to support energy levels and muscle function. It is generally gentle on the digestive system.

Magnesium L-Threonate

Magnesium L-threonate is a specialized form recognized for its ability to cross the blood-brain barrier, making it beneficial for cognitive function. It is also highly absorbable, which limits unabsorbed magnesium in the gut and contributes to its gentle digestive profile.

Comparison of Magnesium Forms


Feature	Magnesium Glycinate	Magnesium Malate	Magnesium Citrate	Magnesium Oxide
Stomach Tolerance	Excellent (very gentle)	Very good (gentle)	Poor (laxative effect)	Very Poor (harsh)
Bioavailability	High	High	Moderate-High	Very Low (poorly absorbed)
Primary Use	Relaxation, sleep, anxiety	Energy, muscle support	Constipation relief	Antacid, short-term laxative
Likelihood of Diarrhea	Very Low	Low	High (at higher doses)	Very High
Common Side Effects	Minimal	Minimal	Diarrhea, cramping	Diarrhea, bloating, gas
Best For	Daily use, sensitive stomachs	Energy support, fatigue	Occasional constipation	Short-term relief, not for deficiency

How to Choose the Right Magnesium for You

Selecting the appropriate magnesium form depends on your health goals and digestive sensitivity. Here’s how to choose:

Determine Your Goal: If you want relaxation and better sleep, magnesium glycinate is a good choice. For energy support, consider magnesium malate. Magnesium citrate is best reserved for occasional constipation relief due to its laxative effect.
Assess Digestive Sensitivity: If you have a sensitive stomach, opt for magnesium glycinate or malate as they are less likely to cause digestive upset.
Start with a Low Dose: Begin with a small dose and gradually increase it to find your tolerance level.
Take with Food: Consuming magnesium with a meal can sometimes improve tolerance.
Look for Quality: Ensure you are getting a pure, well-absorbed product by checking labels for terms like "fully chelated" or "magnesium bisglycinate," as some products may blend with less effective forms.
Consult a Healthcare Professional: Before starting any new supplement, especially if you have health conditions or take other medications, consult a healthcare provider for personalized advice.

Conclusion

Digestive issues from magnesium supplements are often linked to the specific form taken. Forms like magnesium oxide and high doses of magnesium citrate are more likely to cause problems due to their poor absorption and laxative effects. For those seeking a magnesium supplement that doesn't cause stomach issues, highly bioavailable chelated forms such as magnesium glycinate or magnesium malate are generally the best options. By selecting a gentle form and managing your dosage, you can enjoy the benefits of magnesium while maintaining digestive comfort.

NIH Office of Dietary Supplements fact sheet on Magnesium

Frequently Asked Questions

Magnesium glycinate is widely considered the easiest form of magnesium on the stomach. It is a chelated form that is highly absorbable, which prevents large amounts of unabsorbed magnesium from causing digestive upset.

Yes, some magnesium supplements, particularly less absorbable forms like magnesium oxide, can cause gas and bloating. This happens because the unabsorbed mineral draws water into the colon, leading to gastrointestinal side effects.

For a sensitive stomach, magnesium citrate is often not recommended for daily supplementation. It is known for its laxative effect, which can cause loose stools and discomfort, especially at higher doses.

To reduce stomach issues, switch to a more gentle and bioavailable form like magnesium glycinate or malate. You should also start with a lower dosage and take the supplement with food to improve tolerance.

Yes, magnesium bisglycinate is essentially the same as magnesium glycinate. 'Bisglycinate' simply indicates that the magnesium is bound to two glycine molecules, often suggesting an even more stable and bioavailable chelated form.

Yes, it is possible to take magnesium glycinate and citrate together, as they serve different purposes. Glycinate is for calming effects and overall absorption, while citrate provides a laxative effect. However, it is best to consult a healthcare provider before combining them.

The best time to take a gentle magnesium supplement like glycinate is often in the evening or before bed. This can support muscle relaxation and nervous system balance, helping with sleep without causing digestive issues.