Your body needs magnesium for more than 300 enzymatic reactions. It helps you make ATP. It helps your nerves and muscles work properly. It’s one of the most talked-about supplements out there. It’s magnesium.
Things get confusing in the supplement aisle. You’ll pick up one bottle with magnesium oxide, then another that contains magnesium threonate. Which one is better? How much should you take? Keep reading because we’re going to go deeper.
First, What Does Magnesium Do?
Magnesium helps your cells turn food into usable energy. Your body uses ATP to power everything from muscle contractions to protein production. Magnesium binds to ATP and helps your enzymes use that energy.
Your nerves depend on magnesium, too. Nerve cells use electrical activity to communicate with other cells. Magnesium helps regulate that activity, and calcium helps trigger the release of chemical messengers between nerve cells.
Your muscles need both minerals. Calcium helps muscle fibers contract. Magnesium helps regulate contraction and supports relaxation.
Magnesium also supports blood glucose regulation, blood pressure, bone health, normal heart rhythm, and protein production. It also helps reduce migraine frequency.
I’ve recommended magnesium for years, especially for people who are dealing with sleep issues, migraines, or muscle tension. But in reality, most people aren’t getting enough and should be supplementing.
Why You Might Not Be Getting Enough
It’s actually pretty tough to get enough magnesium from food.
You’ll find it in pumpkin seeds, chia seeds, almonds, spinach, cashews, beans, and whole grains. Those are all foods I recommend avoiding if you want to feel good. More on this in a second. Some seafood and dairy products also provide magnesium.
Your health affects magnesium levels, too. Digestive conditions that interfere with nutrient absorption, type 2 diabetes, heavy alcohol use, and certain medications increase the risk of deficiency. Older adults also face a higher risk.
Low magnesium doesn’t always cause obvious symptoms. Symptoms might include reduced appetite, nausea, fatigue, and weakness. Severe deficiency can cause muscle cramps, tingling, seizures, and abnormal heart rhythms.
Foods High in Magnesium
Here are some of the richest sources:
Pumpkin seeds, 1 oz: 156 mg
Chia seeds, 1 oz: 111 mg
Almonds, 1 oz: 80 mg
Cooked spinach, ½ cup: 78 mg
Cashews, 1 oz: 74 mg
Black beans, ½ cup: 60 mg
Dark chocolate, 1 oz: 50 mg
Avocado, ½ cup: 22 mg
Salmon, 3 oz: 26 mg
The recommended daily intake is 400 to 420 mg for men and 310 to 320 mg for women. That’s the bare minimum. Most people feel better with more than this.
Earlier I told you I don’t recommend attempting to get your magnesium from these foods. To get 400 mg from pumpkin seeds alone, you’d need about 2.6 ounces. That’s around 425 calories and 15 g of omega-6 linoleic acid. The standard American diet is already way too high in omega-6 fats. When you eat too many of these fats, you risk increasing body-wide inflammation. The same issue is there with chia seeds.
Ok, but what about spinach? You’d need about 2.6 cups of cooked spinach to reach 400 mg of magnesium. That amount of spinach is going to give you an insane amount of oxalates. Your joints and kidneys will not be happy. Almonds are very high in oxalates and omega-6s too, so that’s not a great option either.
So you probably shouldn’t get magnesium from your food unless you want to eat lots of anti-nutrients and punch yourself in the kidney.
Can You Test Your Magnesium Levels?
Your body stores most of its magnesium inside cells and in bone. Less than 1% circulates in your blood. That creates a limitation with standard testing. Your serum magnesium level might fall within the lab’s reference range even when your cells aren’t getting enough magnesium.
If you want to test, your best option is RBC magnesium. This test measures magnesium inside red blood cells, giving you another look at your intracellular magnesium status. It offers information that a standard serum test doesn’t provide.
RBC magnesium isn’t a 100% perfect measure of magnesium throughout your body. Red blood cells don’t represent every tissue, and labs still use different methods and reference ranges. But I think looking at intracellular magnesium alongside serum magnesium gives you a more useful picture than relying on serum magnesium alone.
Why Are There So Many Types of Magnesium?
Magnesium doesn’t come by itself in most supplements. Manufacturers combine magnesium with another compound. That creates different forms, including oxide, citrate, glycinate, malate, and threonate.
The form affects elemental magnesium content, absorption, and digestive tolerance.
Magnesium oxide contains a high percentage of elemental magnesium by weight, but your body absorbs less of it than several other forms. Magnesium citrate generally absorbs better, but larger doses can cause disaster pants.
When you’re deciding how much to take, you want to take a close look at the label. A supplement might contain 1,000 mg of a magnesium compound without supplying 1,000 mg of elemental magnesium. Always check the elemental magnesium amount.
So which form fits your goals? Does glycinate support sleep? Is citrate a better option for constipation? Does threonate offer an advantage for your brain? And how much magnesium do you need?
Your Magnesium Guide
Here’s what’s coming next:
The different magnesium forms and what they do.
The forms I take and why.
How much magnesium to take and how to read supplement labels.
When to take magnesium.
How magnesium works alongside other minerals.
The specific blend I recommend.
