Many members of DiabetesTeam have wondered about how magnesium levels relate to diabetes. One member commented, “I got a phone call from my doctor’s office. My magnesium is still too low, and I have to increase the tablets. I do eat nuts, beans, and other things that contain magnesium. What I do not know is what causes the deficiency.”

Magnesium is critical for proper cell function throughout the body. Diabetes is associated with magnesium deficiency, which is a lack of adequate magnesium in the body. Research has shown that improving magnesium levels can improve how the body handles blood sugar in both people with diabetes and people who are at higher risk of developing diabetes.

Magnesium

Magnesium is an important electrolyte (like sodium, potassium, and calcium). It’s involved in about 80 percent of the known metabolic processes in the human body — the chemical reactions that keep the body alive and functioning.

Magnesium is essential for the normal function of the heart, muscles, and the nervous system. It helps to maintain cell function, bone health, and normal electrical activity in nerve cells. Magnesium is found in many types of food, including green leafy vegetables, nuts, beans, and whole grains.

Magnesium is mostly absorbed in the small intestine. It’s then stored in tissues throughout the body, including in muscles and bone. The kidneys help maintain healthy magnesium levels by getting rid of excess magnesium in the urine. Diseases that affect the gut, nutrient absorption, or kidney function can all affect magnesium levels.

Magnesium Deficiency

Magnesium deficiency is a lack of adequate magnesium in the body. Low levels of magnesium are linked to a wide range of chronic diseases, including:

• High blood pressure
• Cardiovascular (heart and blood vessels) disease
• Type 2 diabetes
• Migraines
• Osteoporosis (loss of bone tissue causing fragile bones)
• Alcoholism

Magnesium deficiency is a double-edged sword — not only does it increase the risk of chronic diseases, but it can also be caused by chronic diseases.

People with diabetes are at a higher risk of magnesium deficiency, which can lead to poorer blood sugar control and increased risk of serious complications. Low magnesium levels are also associated with worse complications in people with diabetes.

Symptoms

Symptoms of early or mild magnesium deficiency include:

• Loss of appetite
• Nausea and vomiting
• Weakness
• Fatigue

Symptoms of more severe magnesium deficiency include:

• Muscle spasms or cramps
• Tremors
• Vertical nystagmus (abnormal up and down eye movements)
• Numbness or tingling
• Seizures
• Heart arrhythmias (abnormal heartbeats)
• Coma
• Heart attack

Many people with low magnesium do not have any symptoms. However, they are still at higher risk of developing chronic diseases.

Causes

In general, there are three main causes of low magnesium: not getting enough magnesium through the diet for an extended time, having impaired magnesium absorption in the intestines, and having too much magnesium removed by the kidneys.

In people with type 2 diabetes specifically, it appears that the cause of magnesium deficiency is a combination of low magnesium intake and excess magnesium loss in the urine. Kidney disease, often seen in diabetes, can lead to more magnesium loss and a magnesium deficiency.

Certain medications can also lower magnesium levels. These medications include drugs people with diabetes commonly take, such as insulin and diuretics (water pills) like hydrochlorothiazide and furosemide (Lasix).

Other medications that can lower magnesium levels include:

• Proton-pump inhibitors for gastric reflux
• Certain antibiotics
• Chemotherapy drugs
• Drugs used to treat osteoporosis
• Asthma medications
• Chronic obstructive pulmonary disease medications

To avoid developing a magnesium deficiency, talk with your doctor about possibly changing medications. Your doctor can also tell you if any of the medications you’re taking prevent the absorption of magnesium. If so, avoid taking these drugs and magnesium supplements around the same time.

Diagnosis

Magnesium deficiency can be difficult to diagnose. A medical history can identify symptoms, and a physical exam can find physical signs of a deficiency. Laboratory tests, though, are needed to confirm a magnesium deficiency.

Blood tests can show low magnesium levels. However, because less than 1 percent of magnesium in the body is found in the blood, blood levels can appear normal even when you have a deficiency. A 24-hour urine test after an injection of magnesium can better assess magnesium levels or identify increased loss of magnesium in the urine.

Blood tests for other electrolytes, including calcium and potassium, are also helpful for diagnosis. Standard blood tests for kidney function can also be used in diagnosis.

Can Magnesium Improve Diabetes?

Some research indicates that improving magnesium levels can improve blood sugar levels and decrease insulin resistance in people with type 2 diabetes and those at high risk of diabetes, including those with prediabetes or metabolic syndrome.

Although this research sounds promising, the results of studies attempting to show a benefit for people with diabetes from taking magnesium supplements have been mixed. Some studies show a benefit, while others do not. In fact, the American Diabetes Association does not believe there is enough evidence to recommend magnesium supplementation to everyone with diabetes. Larger research studies are needed to investigate the role magnesium supplements can play in helping people with diabetes better manage their condition.

How Can Magnesium Levels Be Improved?

Eating more magnesium-rich foods and taking oral magnesium supplements can improve your body’s magnesium levels. Treating underlying conditions that may affect magnesium levels is also important.

Diet

Research suggests that many people do not get enough magnesium in their diet. Getting magnesium from food is perhaps the best way to maintain your magnesium levels. The body absorbs magnesium from food well, and you are at low risk of getting too much magnesium from food. The recommended daily intake of magnesium from food varies greatly by age and gender.

Foods that are high in magnesium include:

• Pumpkin and chia seeds
• Almonds, cashews, and peanuts
• Peanut butter
• Beans and legumes (black beans, kidney beans, and edamame)
• Soy milk
• Spinach
• Potatoes with skin
• Whole grains (whole wheat bread, oatmeal, and brown rice)
• Milk and yogurt
• Avocados
• Bananas
• Raisins
• Salmon and halibut
• Ground beef
• Chicken breast
• Fortified foods, like breakfast cereals

Magnesium Supplements

Depending on your specific needs, your doctor might ask you to take supplemental magnesium to restore and maintain proper magnesium levels. Oral magnesium supplements come in many forms. Some are absorbed better than others. Some are also more likely to cause side effects, such as diarrhea. Talk with your doctor to see which form is best for you.

When taking magnesium supplements, there is some risk of getting too much magnesium. High levels of magnesium can cause low blood pressure, nausea, vomiting, diarrhea, cramping, urinary retention, abnormal heart rhythms, and even cardiac arrest. Having kidney failure can also contribute to high magnesium if the kidneys cannot remove excess magnesium from the body.

Talk to Your Doctor

If you are concerned about your magnesium levels, discuss it with your doctor or other health care provider. Checking your magnesium levels — both in your blood and urine — can give a clearer picture of how your body is handling magnesium. If you take any prescription medications, you should always discuss potential side effects with your doctor, including their effect on magnesium levels.

Unless you have kidney failure or any serious kidney disease, increasing your dietary intake of magnesium is likely a safe way to raise magnesium levels. If you are considering taking magnesium supplements, it is best to discuss this with your health care provider first. You should always talk with your doctor before making any significant changes in your diet, medications, or nutritional supplements.

Talk With Others Who Understand

DiabetesTeam is the social network for people with diabetes and their loved ones. On DiabetesTeam, more than 118,000 members come together to ask questions, give advice, and share their stories with others who understand life with diabetes.

Have you discussed your magnesium levels with your doctor? Share your experience in the comments below, or start a conversation by posting on your Activities page.