Magnesium Citrate vs. Magnesium Bisglycinate: Which Is Right for You?

Magnesium is an essential mineral that supports over 300 processes in your body. But when you're shopping for a magnesium supplement, the options can feel overwhelming.

Two popular forms are magnesium citrate and magnesium bisglycinate. While both can help you meet your magnesium needs, they work differently in your body and are better suited for different purposes.

Here's what you need to know to choose the right one for you.

Key takeaways

• Magnesium citrate works well for constipation relief and raising low magnesium levels quickly, but it can cause digestive upset like diarrhea and cramping.

• Magnesium bisglycinate is gentler on your stomach and better for sleep, stress, and long-term daily use, though it costs more than citrate.

• Your choice should depend on your health goals: pick citrate if you need help with constipation, or bisglycinate if you want support for sleep and relaxation without digestive side effects.

What is magnesium citrate?

Magnesium citrate is magnesium bound to citric acid. This combination makes it one of the most common and affordable magnesium supplements available.

How it works

When you take magnesium citrate, it draws water into your intestines. This softens your stool and helps things move along, which is why it has a natural laxative effect.

Absorption

Your body absorbs magnesium citrate relatively well compared to forms like magnesium oxide. Studies suggest it has an absorption rate of around 30%.

Best uses

Magnesium citrate may be helpful for occasional constipation, quickly raising low magnesium levels, and people who don't have sensitive stomachs.

Potential side effects

Because of its laxative properties, magnesium citrate can cause diarrhea or loose stools, stomach cramping, nausea, and bloating.

What is magnesium bisglycinate?

Magnesium bisglycinate (also called magnesium glycinate) is magnesium bound to two glycine molecules. Glycine is an amino acid that acts as a calming neurotransmitter in your brain.

How it works

The glycine in this supplement helps the magnesium absorb better and makes it much gentler on your digestive system. Unlike magnesium citrate, it doesn't pull water into your intestines.

Absorption

Magnesium bisglycinate is considered one of the most bioavailable forms of magnesium. This means your body can absorb and use it efficiently, with minimal waste.

Best uses

Magnesium bisglycinate may be helpful for improving sleep quality, reducing stress and anxiety, easing muscle tension, long-term supplementation, and people with sensitive digestive systems.

Potential side effects

Magnesium bisglycinate typically causes fewer side effects than other forms. However, some people may experience mild drowsiness, nausea (usually only at very high doses), or digestive discomfort (rare).

Key differences between the two

Digestive effects

The most significant difference is how these supplements affect your digestive system.

Magnesium citrate acts as an osmotic laxative, which can be helpful if you're constipated but may be disruptive if you're not.

Magnesium bisglycinate doesn't have this laxative effect, making it a better choice for daily supplementation when you want the benefits of magnesium without worrying about bathroom emergencies.

Calming effects

While all forms of magnesium have relaxing properties, magnesium bisglycinate may be more effective for sleep and stress.

This is because the glycine in the supplement has its own calming effects. Research shows glycine can improve sleep quality and reduce feelings of anxiety. When you combine magnesium's muscle-relaxing properties with glycine's calming effects on your brain, you get a powerful combination for better sleep.

Cost

Magnesium citrate is generally more affordable and widely available. You can find it at most drugstores and supermarkets.

Magnesium bisglycinate costs more due to its specialized manufacturing process, but many people find the gentler experience worth the extra expense, especially if they plan to take it daily for an extended period.

Speed of action

If you're using magnesium for constipation relief, citrate works faster—often within 30 minutes to 6 hours.

For other benefits like better sleep or reduced muscle tension, bisglycinate may take several days to weeks of consistent use to show noticeable results.

Which form should you choose?

The best magnesium supplement depends on your specific health goals.

Choose magnesium citrate if you:

• Need occasional help with constipation

• Want a more budget-friendly option

• Need to quickly address a magnesium deficiency

• Don't have digestive sensitivity

Choose magnesium bisglycinate if you:

• Want support for sleep or relaxation

• Experience stress or occasional feelings of anxiety

• Have a sensitive stomach 

• Deal with muscle cramps or tension

• Want to take magnesium long-term

• Have trouble with other forms causing diarrhea

How much magnesium do you need?

The recommended dietary allowance (RDA) for magnesium varies by age and gender.

For adult women, the RDA is 310 mg for ages 19-30 and 320 mg for ages 31 and older. For adult men, it's 400 mg for ages 19-30 and 420 mg for ages 31 and older.

Keep in mind that these amounts include magnesium from both food and supplements. The tolerable upper intake level for supplemental magnesium is 350 mg per day for adults. Going above this amount increases your risk of side effects like diarrhea.

Most magnesium supplements contain between 200-400 mg per serving. Start with a lower dose and increase gradually to see how your body responds.

Can you take both forms?

Yes, some people use both types strategically. For example, you might take magnesium bisglycinate daily for sleep support and keep magnesium citrate on hand for occasional constipation.

Just be mindful of your total daily magnesium intake to avoid exceeding the recommended limits. Add up the magnesium content from all your supplements to ensure you're staying within safe ranges.

Signs you might need magnesium

Many Americans don't get enough magnesium from their diets alone. Studies suggest that nearly half of U.S. adults consume less than the recommended amount.

Common signs of low magnesium include occasional feelings of muscle cramps or spasms, fatigue or weakness, poor sleep quality, irritability, and inability to relax. 

If you experience these symptoms regularly, talk with your healthcare provider about whether a magnesium supplement might help. They can order a blood test to check your magnesium levels, though it's worth noting that blood tests don't always accurately reflect your body's total magnesium stores.

Safety and precautions

Magnesium supplements are generally safe for most people, but there are some important considerations.

Talk to your doctor before taking magnesium if you have kidney disease or reduced kidney function, take medications like antibiotics, bisphosphonates, or diuretics, have heart conditions or take heart medications, or are pregnant or breastfeeding.

High doses of magnesium can interfere with certain medications and cause serious side effects in people with kidney problems. Your kidneys are responsible for removing excess magnesium from your body, so impaired kidney function can lead to dangerous magnesium buildup.

Getting magnesium from food

While supplements can help fill gaps, it's important to also focus on magnesium-rich foods in your diet.

Good food sources of magnesium include dark leafy greens like spinach and Swiss chard, nuts and seeds (especially almonds, cashews, and pumpkin seeds), legumes such as black beans and chickpeas, whole grains like quinoa and brown rice, dark chocolate with at least 70% cocoa, avocados, and bananas.

Aim to include several servings of these foods in your daily diet. Food sources of magnesium don't count toward the 350 mg supplement limit and are generally easier for your body to process.

The bottom line

Both magnesium citrate and magnesium bisglycinate can help you meet your magnesium needs, but they work differently in your body.

Magnesium citrate is affordable and effective. However, its laxative effects may not be ideal for everyone, particularly if you're looking for daily supplementation without digestive disruption.

Magnesium bisglycinate is gentler on your stomach and better suited for sleep, stress relief, and long-term use. The additional expense may be worthwhile if you experience digestive sensitivity with other forms or if you're taking magnesium primarily for its calming and muscle-relaxing benefits.

Consider your health goals, budget, and how your body responds to different supplements. When in doubt, consult with a healthcare professional to determine which form is right for you. They can help you assess your specific needs and recommend the most appropriate type and dosage.