Magnesium Deficiency: What Causes Low Magnesium?

The information in this article and throughout Trio Nutrition's blog is for informational purposes only and should not replace professional medical advice. For questions about our products or orders, please contact Trio Nutrition. Written, read and reviewed by the Trio Nutrition team.

Magnesium deficiency is less common than low magnesium intake, but the two are linked. The NIH Office of Dietary Supplements (NIH ODS) reports that 48% of Americans get less magnesium from food and drinks than their estimated needs. Below, Trio Nutrition explains the signs, causes, daily needs and food sources NIH ODS describes, with links to each Trio Nutrition magnesium guide.*

What is magnesium deficiency, and how common is it?

Magnesium helps the body regulate muscle and nerve function and make protein, bone and DNA, according to the NIH ODS consumer fact sheet. An adult body holds about 25 grams of magnesium, and 50% to 60% of it is in bone. Less than 1% is in blood serum, so NIH ODS notes that serum levels do not accurately reflect total body magnesium.*

NIH ODS explains that short-term low intake does not produce obvious symptoms. The kidneys limit how much magnesium is lost in urine. Over a long period, low intake can lead to magnesium deficiency. Men older than 70 and teenagers are most likely to have low intakes. NIH ODS adds that no single method is considered satisfactory for assessing magnesium status. A provider may look at diet, symptoms and health history together. Learn more about magnesium and nerve function and magnesium and calcium absorption.*

What are the signs of magnesium deficiency?

NIH ODS lists these early signs of magnesium deficiency:

• Loss of appetite.*
• Nausea and vomiting.*
• Fatigue and weakness.*

As deficiency becomes more severe, NIH ODS notes that numbness, tingling, muscle contractions and cramps, seizures, personality changes and an abnormal heart rhythm can occur. Many of these signs have other causes, so they do not prove low magnesium on their own. For related topics, see magnesium for muscle soreness and the reasons people start taking magnesium.*

What causes low magnesium?

NIH ODS describes three main routes to deficiency: low intake over a long period, conditions that reduce absorption, and conditions or medicines that increase how much magnesium the body excretes. It names four groups more likely to get too little magnesium:*

• Digestive conditions: people with certain gastrointestinal conditions.*
• Metabolic conditions: people with a common long-term blood-sugar condition.*
• Alcohol: people with long-term alcohol dependence.*
• Age: older adults.*

NIH ODS also lists medicines that can interact with magnesium, including bisphosphonates, some antibiotics, diuretics and proton pump inhibitors. Busy routines affect sleep and stress too. Trio Nutrition covers those topics in guides to magnesium for stress, a calming magnesium supplement and magnesium for a calmer mood.*

How much magnesium do adults need each day?

The amount of magnesium you need depends on your age and sex. The NIH ODS consumer fact sheet lists these average daily recommended amounts:*

NIH ODS notes that when magnesium from food and supplements is combined, total intakes are generally above recommended amounts. Food records or a nutrition app can show how close your diet comes to these amounts. For more on timing and routines, read about magnesium for sleep and improving sleep with magnesium.*

How can you support healthy magnesium levels?

NIH ODS states that good sources of magnesium include green leafy vegetables, legumes, nuts, seeds, whole grains and certain beverages. These foods are among the richest sources it lists:*

Magnesium is sold in multivitamin and mineral products and in other dietary supplements. It is also an ingredient in some laxatives and heartburn products. NIH ODS states that forms that dissolve well in liquid are absorbed more completely, and it names magnesium aspartate, citrate, lactate and chloride as more easily absorbed forms. Trio Nutrition explains other forms in guides to magnesium glycinate benefits, magnesium bisglycinate vs glycinate and high-absorption magnesium forms. Some readers also look into magnesium for migraines or magnesium with vitamin B6.*

Magximum and Magnesium Complex: what is in each serving?

Trio Nutrition's Magximum supplies magnesium glycinate 210 mg (50% DV), vitamin D3 10 mcg (50% DV), vitamin K2 (MK-7) 60 mcg (50% DV) and MCT oil 200 mg per two-capsule serving.* That is 105 mg of magnesium per capsule, and up to 5 capsules (525 mg) can be taken when recommended by a healthcare practitioner. A bottle holds 120 capsules, a 60-day supply.

Magnesium Complex supplies 420 mg of magnesium (100% DV) from magnesium glycinate and magnesium oxide, plus vitamin B6 2 mg, per two-capsule serving.* A bottle holds 180 capsules, a 90-day supply. Both are vegetarian, with no major food allergens, and backed by a 60-day full-refund guarantee — no return required^*. Compare them in Magximum vs Magnesium Complex or read about Magnesium Complex benefits.

Why Customers Choose Trio Nutrition

• Magximum combines magnesium glycinate with vitamins D3 and K2 and MCT oil.*
• Magnesium Complex gives 420 mg of magnesium (100% DV) per serving, a 90-day supply.*
• Manufactured in the USA in an FDA-registered, GMP-certified facility, and lab tested.
• Vegetarian capsules with no major food allergens.
• Backed by a 60-day full-refund guarantee — no return required*.

The bottom line on magnesium deficiency

Magnesium deficiency usually develops over time, through long-term low intake, some health conditions or some medicines. Watch for early signs such as fatigue and weakness, eat magnesium-rich foods, and compare your intake with the NIH ODS amounts for your age and sex.* If you consider a supplement, talk with your healthcare provider first.

Frequently asked questions

What is magnesium deficiency?

Magnesium deficiency means the body has less magnesium than it needs. The NIH Office of Dietary Supplements (NIH ODS) explains that in healthy people the kidneys limit how much magnesium is lost in urine, so low intake rarely causes symptoms in the short term. Low intake over a long period, some health conditions and some medicines can lead to deficiency. NIH ODS also reports that 48% of Americans get less magnesium from food and drinks than their estimated needs.*

What are the signs of low magnesium?

In its fact sheet updated January 6, 2026, NIH ODS lists loss of appetite, nausea, vomiting, fatigue and weakness as early signs of magnesium deficiency. As deficiency becomes more severe, numbness, tingling, muscle contractions and cramps, seizures, personality changes and an abnormal heart rhythm can occur. These signs have many possible causes. A healthcare provider can check whether low magnesium is involved.*

What causes low magnesium?

Low magnesium can come from low intake over a long period, or from conditions and medicines that reduce absorption or increase losses, according to NIH ODS. The NIH ODS consumer fact sheet, updated in 2021, names four groups more likely to get too little magnesium: people with certain digestive conditions, people with a common long-term blood-sugar condition, people with long-term alcohol dependence, and older adults. Proton pump inhibitors and some diuretics are among the medicines NIH ODS lists as interacting with magnesium.*

How much magnesium do adults need?

The NIH ODS consumer fact sheet lists 400 to 420 mg a day for men and 310 to 320 mg a day for women, depending on age. Pregnant women need 350 to 360 mg, and breastfeeding women need 310 to 320 mg. Trio Nutrition Magximum supplies 210 mg of magnesium glycinate per two-capsule serving, and Magnesium Complex supplies 420 mg (100% DV) per two-capsule serving.*

Can food alone fix low magnesium?

NIH ODS states that people can get recommended amounts of magnesium by eating a variety of foods, including legumes, nuts, seeds, whole grains and green leafy vegetables. One ounce of roasted pumpkin seeds provides 156 mg, and one ounce of dry-roasted almonds provides 80 mg. When low magnesium is linked to a health condition or medicine, food may not be enough, so a healthcare provider should guide the plan.*

Does the form of a magnesium supplement matter?

NIH ODS states that forms of magnesium that dissolve well in liquid are absorbed more completely. The NIH ODS consumer fact sheet names magnesium aspartate, citrate, lactate and chloride as more easily absorbed forms. Small studies found these forms more bioavailable than magnesium oxide and sulfate. Trio Nutrition Magximum uses magnesium glycinate, and Magnesium Complex combines magnesium glycinate with magnesium oxide.*

*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Consult your healthcare provider before starting any supplement.

All Trio Nutrition products are Manufactured in the USA and lab tested in FDA-registered facilities.

Important Notice: Always consult your healthcare provider prior to taking any nutritional supplements, especially if you are pregnant, nursing, taking medication, have a medical condition, or are planning any medical procedure. Discontinue use and consult your doctor if any adverse reactions occur. Keep out of reach of children.

Disclaimer: This information is for educational purposes only and is not intended as medical advice. Individual results may vary.

Sources & Further Reading

• National Institutes of Health, Office of Dietary Supplements. Magnesium — Health Professional Fact Sheet. Updated January 6, 2026.
• National Institutes of Health, Office of Dietary Supplements. Magnesium — Fact Sheet for Consumers. Updated March 22, 2021.

— The Trio Nutrition Team