There are many nutrients that your body needs every day to function optimally. One of these is magnesium, which has some specific implications for brain health.
[See: Best Foods for Brain Health.]
What Is Magnesium?
“Magnesium plays a fundamental role in the regulation of various biological processes that are necessary to function well,” says Candace Pumper, a staff dietitian with the Ohio State University Wexner Medical Center in Columbus.
This mighty mineral is used in more than 300 enzyme systems within the body that contribute to:
— Creating energy.
— Transporting electrolytes across cell membranes.
— Making DNA and RNA.
— Synthesizing protein.
— Contracting muscles, including the heart.
— Regulating blood pressure.
— Controlling calcium levels inside cells.
The Recommended Dietary Allowance, or RDA, of magnesium for adults is 400 to 420 milligrams per day for men, and 310 to 320 milligrams per day for women. Pregnant people need between 350 and 360 milligrams of magnesium daily.
Magnesium for Brain Health
Magnesium’s role in helping the body produce energy is critically important, “because over 20% of all energy produced in the body is consumed by the brain,” says Dr. Michael del Junco, an internal medicine specialist with Providence St. Joseph Hospital in Orange County, California.
As such, magnesium plays a pivotal role in brain health. “Proper levels of magnesium ensure optimal nerve transmission and neuromuscular conduction, and protects against excess neuron excitation and oxidative stress,” del Junco says. Which, put quite simply, means that if you don’t have the appropriate levels of magnesium, it can lead to reduced cognitive performance. “Abnormal levels of magnesium have even been linked to disorders such as migraines, depression, chronic pain, stroke, seizures and dementia.
Magnesium is also essential to ensuring the normal function of neurons and helps regulate neurotransmitters, which are the chemical messengers that help the cells of the brain communicate with each other, and with the rest of the body.
Two neurotransmitters in particular — glutamate and gamma-aminobutyric acid, or GABA — are dependent on appropriate levels of magnesium.
“Glutamate plays a major role in normal brain functioning, including shaping learning and memory,” Pumper says. “For the brain to function properly, glutamate levels need to be tightly controlled. Any imbalance can disrupt nerve cell communication.”
Low levels of magnesium can lead to excess glutamate in the brain. When this happens, “nerve cells can become overexcited, leading to nerve cell damage and death, a condition known as glutamate excitotoxicity,” Pumper says. “Glutamate excitotoxicity has been implicated in many neurodegenerative conditions, such as ALS (Lou Gehrig’s disease), multiple sclerosis, Alzheimer’s disease, Parkinson’s disease, Huntington’s disease and epilepsy.”
A 2018 review study published in the journal Nutrients found that there is “strong data to suggest a role for magnesium in migraine and depression” and that there is “emerging data” to suggest that magnesium has a protective effect in conditions of chronic pain, anxiety and stroke. “More research is needed on magnesium as an adjunct treatment in epilepsy and to further clarify its role in Alzheimer’s and Parkinson’s”
What is known currently, Pumper says, is that “adequate magnesium levels appear to be protective against chronic disease and supportive of brain health, and low magnesium status is increasingly linked to disease risk, including neurological and psychiatric disorders and impaired disease management.”
Magnesium Food Sources
— Nuts and seeds.
— Greens and vegetables.
— Whole-grain products.
— Low-fat dairy products and soy.
— Chocolate or cocoa.
Nuts and Seeds
— Pumpkin seeds, hulled, roasted: 1 ounce = 156 milligrams of magnesium.
— Chia seeds: 1 ounce = 111 milligrams.
— Almonds, dry roasted: 1 ounce = 80 milligrams.
— Cashews, dry roasted: 1 ounce = 74 milligrams.
— Peanuts, dry roasted: 1 ounce = 49 milligrams.
— Peanut butter, smooth: 2 tablespoons = 49 milligrams.
— Flaxseed, whole: 1 tablespoon = 40 milligrams.
Greens and Vegetables
— Spinach, cooked: ½ cup = 78 milligrams.
— Potato, baked with skin: 3.5 ounces = 43 milligrams.
— Black beans, cooked: ½ cup = 60 milligrams.
— Edamame, cooked: ½ cup = 50 milligrams.
— Lima beans, cooked: ½ cup = 40 milligrams.
— Quinoa, cooked: ½ cup = 60 milligrams.
— Cereal, shredded wheat: 2 large biscuits = 61 milligrams.
— Rice, brown, cooked: ½ cup = 42 to 44 milligrams.
— Wheat germ: 2 tablespoons = 35 milligrams.
— Bread, whole wheat: 2 slices = 46 milligrams.
Low-fat Dairy Products and Soy
— Soy milk, plain or vanilla: 8 ounces = 61 milligrams.
— Yogurt, plain or low fat: 8 ounces = 42 milligrams.
— Milk, nonfat: 8 ounces = 24-27 milligrams.
Chocolate or Cocoa
— Dark chocolate, 70-85% cocoa: 1 ounce = 64 milligrams.
— Dark chocolate, 60-69% cocoa: 1 ounce = 50 milligrams.
The amount of magnesium found in these foods can fluctuate depending on local agricultural practices, how they’re fertilized and how they’ve been processed, refined or cooked, Pumper says.
Some foods, such as some breakfast cereals, are fortified with extra magnesium.
Pumper adds that some bottled mineral and tap water sources can contain magnesium and can “provide portions of the RDA of this mineral. But the amount varies by source and brand with a range of 1 milligram per liter to 120 milligrams per liter.”
Should I Take a Magnesium Supplement?
Del Junco says that if your magnesium levels are normal, you should “avoid supplementation. No current evidence suggests that magnesium supplementation will provide any measurable benefit to a patient with normal magnesium levels.”
However, some people may not be getting enough magnesium in their diets. Del Junco notes that signs of abnormal magnesium levels are often vague and nonspecific, but may include:
— Poor appetite.
— Poor concentration.
— Muscle spasms.
Your doctor can test whether your levels of magnesium are out of whack. Certain populations may be at a greater risk of magnesium deficiency including:
— Older adults.
— Patients who have uncontrolled diabetes.
— Patients with chronic diarrhea or other digestive disorders that cause them difficulty in absorbing nutrients from food.
— People who consume alcohol daily.
— People who take certain medications, including proton pump inhibitors (such as omeprazole for gastroesophageal reflux disease) and loop or thiazide diuretics (such as furosemide, hydrochlorothiazide and chlorthalidone which may be used for congestive heart failure, high blood pressure and other cardiac conditions).
If you’re deficient in this nutrient, del Junco recommends “attempting to increase your magnesium intake through your diet. If you’re unable to absorb enough magnesium from your diet, consider a supplement.”
Pumper agrees that food first is best. “Magnesium supplementation can certainly help fill gaps in a nutrient-deficient diet, but the challenge is discerning which products to choose. For consumers, talking with your doctor before adding a magnesium supplement to your routine is a good first step.”
If you and your health care provider determine that supplementation is a good idea, Pumper recommends considering the following when choosing a product:
— The ideal form and dosage for your needs. “Magnesium supplements are available in different forms, each with differing absorbability, benefits and effects on the body.” Common forms include magnesium citrate, magnesium oxide, magnesium glycinate, magnesium chloride and magnesium sulfate. Del Junco says that magnesium citrate is the most readily absorbed form of magnesium supplement when taken orally. So, what’s the best form of magnesium supplement for brain health? “Magnesium citrate is often used to address low levels of magnesium and may also be effective as an acute treatment option for migraine headaches,” Pumper says. “This form is gentle on the stomach, has good absorbability and is safe,”
— Quality of the product. Pumper recommends selecting products that have “quality seals of certification on the product labels to assure product integrity.” Certifying bodies include ConsumerLab.com, NSF International or the U.S. Pharmacopeial Convention.
— Other medications you’re taking. Supplements can sometimes interact negatively with other medications or supplements you may be taking, so it’s very important to check with your health care provider before adding any herbal or dietary supplement product. Magnesium supplements in particular sometimes interact with and decrease the absorption of certain medications including antibiotics, diuretics, proton pump inhibitors, bisphosphonates (which are used to treat bone conditions like osteopenia and osteoporosis) and high doses of zinc (above 142 milligrams per day).
— Medical conditions you have. People who have chronic kidney disease should not take magnesium supplements, as they can cause high amounts of magnesium to accumulate in the blood and lead to muscle weakness.
Taking too much magnesium can cause side effects, including abdominal cramping and diarrhea. “If you experience these symptoms, reduce your daily dose,” del Junco says. It’s also best to contact your health care provider for additional guidance.
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