Magnesium: A Review of How to Test and What Forms To Use.

If you’re taking a magnesium supplement, do you know what form you’re taking and if that form is what you need?

These are a few of the topics addressed in this post.

Before I get started…Before taking magnesium, be sure to consult with a healthcare provider who is educated in nutrition. 

Magnesium is the fourth most abundant mineral in your body. It’s estimated that 75% of Americans do not meet their daily intake requirements. This is a problem. It’s involved in over 300 metabolic reactions that have to do with energy production, blood pressure regulation, nerve signal transmission, muscle contraction and numerous other processes. Low levels have been linked to a number of illnesses (type 2 diabetes, heart disease, mood disorders, migraines, etc.). 

TESTING:

Best test for an accurate measurement of magnesium levels is MAGNESIUM RBC (red blood cell levels)

 

POTENTIAL HEALTH BENEFITS:

• blood pressure (including eclampsia and preeclampsia)

• blood sugar regulation (including metabolic syndrome, diabetes and diabetic neuropathy)

• muscle health (including muscle aches, performance and recovery, restless leg syndrome)

• mental health (including anxiety, depression) Check out this study that showed 248mg of elemental magnesium per day for 6 weeks improved both anxiety and depression and “may allow for lower antidepressant dosage or avoid the need for use of a second medication, both of which could reduce overall side effect burden”. 

• chronic stress

• constipation

• sleep

• asthma

• migraines, headaches

• bone health, improve vitamin D absorption 

• pregnancy

• smoking cessation

HOW WELL IS MAGNESIUM ABSORBED?

Short answer: 

Not well. It has to be bound to something else (citrate, malate, etc.). Other nutrients, like calcium) can further decrease absorption, so take on an empty stomach. 

Long answer:

Magnesium is a small molecule that is unstable by itself. It needs to be bound to something else to be stable. This is why you see magnesium in various “forms” like citrate, malate, glycinate, etc. Also, it’s not absorbed through the GI tract very well. Studies show a varying degree of absorption, somewhere between 30-45%. This variation is also dependent upon the size and absorption of the molecule it’s attached to. Magnesium citrate is the best absorbed form (but it’s bonded to a large molecule so there’s a smaller amount of magnesium by weight). Magnesium oxide is the most poorly absorbed (but it’s bonded to a small molecule and has a higher amount of magnesium by weight). Confused yet? No worries. I’ll go into a bit more detail with each form. Also note, other nutrients can compete or reduce absorption of magnesium. These include calcium, high protein intake, high zinc intake, and phytates in veggies, to name just a few. A low calcium concentration in the intestines actually helps improve magnesium absorption. So, be sure to take your magnesium on an empty stomach. Otherwise, you’ll likely need to take much higher doses to improve blood and cell levels. Other things that can increase risk of deficiency are: alcohol, coffee, high estrogen levels, high cortisol levels, high-sugar diet (glucose, fructose, sucrose), malabsorption of any sort (celiac or Crohn’s disease, pancreatitis, crash dieting, anorexia), and mineral oil.

DIFFERENT FORMS OF MAGNESIUM:

Magnesium L-Threonate

Short answer:
My favorite and most widely used form. This is the only form shown to cross the blood-brain barrier, so it’s particularly suited for conditions like anxiety/depression, sleep and cognitive decline. My favorite product is HERE.

Long answer:

Magnesium L-threonate is the salt formed from mixing magnesium and threonic acid, a water-soluble substance derived from the breakdown of vitamin C. This form is easily absorbed and studied for its benefits in conditions like anxiety, depression, medication-resistant sleep disorders and cognitive diseases (like Alzheimers). A study published in the medical journal Neuron showed this form showed improvement in learning abilities, working memory and both short and long term memory. 

Magnesium Malate

Short answer:

My second favorite and most widely used form. Quickly absorbed. Used more in musculoskeletal issues and conditions like: sore muscles, exercise performance and recovery, fibromyalgia and chronic fatigue syndrome.  My favorite product is HERE.

Long answer:

This type of magnesium is a compound of magnesium and malic acid. A 2019 study found that out of several types of magnesium, magnesium malate was the fastest to absorb after a single dose. Malic acid has a sour taste and is often used as a food additive to enhance flavor or add acidity. I have found that it tends to be gentler on the GI system and may have less of a laxative effect than other types. I tend to use this form especially for musculoskeletal issues, like sore muscles, exercise performance and recovery, fibromyalgia and chronic fatigue syndrome. 

Magnesium Glycinate

Short answer:

It’s the combination of magnesium and glycine (an amino acid), well absorbed and typically used for its calming properties (sleep, anxiety, stress, etc). My favorite product is HERE.

Long answer:

Magnesium glycinate is a compound of magnesium and glycine, an amino acid. Research indicates it is tolerated well and that it seems to cause minimal side effects. This means it may be a good option for people who require higher doses or who experience side effects when using other types of magnesium. It’s often used for its calming properties (likely because glycine is also calming) to improve sleep, anxiety and stress. It’s also been researched in treating a variety of inflammatory conditions, including heart disease and diabetes. 

Magnesium lactate

Short answer:

Mostly used as a food additive/preservative and less as a supplement. Well absorbed with fewer GI side effects as other forms, so may be a good option if you need to take high doses of magnesium. 

Long answer:

This type of magnesium is a compound of magnesium and lactic acid. According to a 2017 study, it appears to absorb in the gut easily. Magnesium lactate is the salt formed when magnesium binds with lactic acid. This acid is not only produced by your muscle and blood cells but also manufactured for use as a preservative, to regulate acidity and fortify foods and beverages. Its ease of absorption may mean it can be a little gentler on your digestive system than other types. This is particularly significant for people who need to take large doses of magnesium regularly or don’t easily tolerate other forms. In a study in 28 people with a rare condition that required high doses of magnesium daily, those who took a slow-release tablet of magnesium lactate had fewer digestive side effects than the control group. 

Magnesium citrate

Short answer:

The most popular (and one of the cheapest) supplement forms. Used often to treat constipation. My favorite product is HERE.

Long answer: 

Magnesium citrate is one of the most popular (and cheapest) forms of magnesium. It is often an ingredient in supplements and appears to be easier for the body to absorb than some other forms. A 2003 study of 46 adults found that it absorbed better than magnesium oxide and magnesium chelate. It’s used very often by doctors to treat constipation. It’s bound with citric acid, found naturally in citrus fruits and gives them their tart, sour flavor. Artificially produced citric acid is often used as a preservative and flavor enhancer in the food industry. Unfortunately, much of the citric acid today is made from Aspergillus niger, a type of black mold. Yep, that’s right. I’ve treated many patients with conditions triggered or exacerbated by pathogenic molds. It’s no fun. So, if you decide to use this form, be sure to go with a manufacturer who has stellar quality control and assurance standards. 

Magnesium Orotate

Short answer:

Well absorbed. Not much of a laxative effect. Tends to be used mostly in heart disease and by athletes. 

Long Answer:

Magnesium orotate includes orotic acid, a natural substance involved in your body’s construction of genetic material, including DNA. It’s easily absorbed and doesn’t have the strong laxative effects characteristic of other forms. Some research suggests that it may promote heart health due to orotic acid’s unique role in the energy production pathways in your heart and blood vessel tissue. It’s also popular among competitive athletes and fitness enthusiasts, likely for its cardioprotective properties. One study in 79 people with severe congestive heart failure found that it was significantly more effective for symptom management and survival than a placebo. However, this form tends to be significantly more expensive than other magnesium supplements. 

Magnesium taurate

Short answer: 

Like the orotate form, it is used mostly to protect the heart and lower blood pressure, but may also be useful in the prevention of diabetes.

Long answer: 

This type of magnesium is a compound of magnesium and taurine.  It is used often to lower blood pressure and protect the cardiovascular system. One study reports it reduced high blood pressure and heart damage in rats that had taken a toxic substance (to try and induce heart damage). Also, research has shown that adequate amounts of taurine and magnesium are needed for regulating blood sugar. 

 

TOPICAL USE

If you are sensitive to magnesium (easily get GI distress from it), you may want to go with a topical (transdermal) instead. The skin tends to absorb it (not as well as orally) and can be especially beneficial for reducing muscle soreness, insomnia and acute stress reactions. Epson salt (a combo of magnesium, sulfur, and oxygen) in a hot bath or foot soak is a popular means for this method. There are also topical gels that can be effective.

 

RECOMMENDED USE

The recommended dietary allowance (RDA) of magnesium for adult men is 400-420mg. For adult women, it’s 310-360mg (400mg if pregnant or lactating). If you have chronic condition (like diabetes, heart disease, autoimmune disease, etc.) or a GI disorder that affects absorption, you may need a higher dose. 

 

FOOD BEFORE SUPPLEMENTS

I always recommend trying first to get your nutrients from food. There are a couple of reasons for this. 

(1) Nutrients from food sources are often better assimilated (more easily broken down and absorbed) than supplements. This is especially the case with many cheap, poorly manufactured products. 

(2) There’s a psychological shift that happens when you change your lifestyle habits (like diet) that does not occur as strongly when taking a supplement. In addition, I’ve found some people think they can supplement their way out of a bad diet. This is dangerous as well because it often does not lead to longterm change. 

There’s nothing wrong with taking supplements. But, they should be just that…supplemental (to other good habits). If you have a chronic condition, as mentioned above, dietary intake may not be enough. 

 

FOOD SOURCES OF MAGNESIUM

• roasted pumpkin seeds (37% of RDA per ounce)

• chia seeds (26% of RDA per ounce)

• almonds (19% of RDA per ounce)

• boiled spinach (19% of RDA per 1/2 cup)

• find more sources HERE

 

TOXICITY

Although rare, magnesium toxicity can occur. If you have kidney disease or consume very large doses of this mineral, you may be at a greater risk. Signs of toxicity include nausea, vomiting, diarrhea, muscle weakness, irregular breathing, lethargy, and urinary retention. 

 

MEDICATIONS THAT MAY CAUSE MAGNESIUM DEFICIENCY

• Diuretics like furosemide (Lasix), bumetanide, chlorthalidone and hydrochlorothiazide often deplete magnesium along with potassium.

• Reflux/antacid medications like dexlansoprazole (Dexilant), esomeprazole (Nexium), lansoprazole (Prevacid), omeprazole (Prilosec), pantoprazole (Protonix) and rabeprazole (Aciphex) may reduce absorption of magnesium from food/supplementation. 

• Antibiotics like Amoxicillin (Amoxil), Azithromycin (Z-Pak), Cefaclor (Ceclor), Cefdinir (Omnicef), Cephalexin (Keflex), Ciprofloxacin (Cipro), Clarithromycin (Biaxin), Doxycycline (Doryx), Erythromycin (E.E.S.), Levofloxacin (Levaquin), Minocycline (Minocin), Sulfamethoxazole and trimethoprim (Bactrim, Septra), Tetracycline (Sumycin)

• Antivirals like Delavirdine (Rescriptor), Foscarnet (Foscavir), Lamivudine (Epivir), Nevirapine (Viramune), Zidovudine, AZT (Retrovir), Zidovudine and Lamivudine (Combivir)

• Blood pressure meds like Hydralazine (Apresoline), Enalapril and HCTZ (Vaseretic), Valsartan and HCTZ (Diovan HCT), Bumetanide (Bumex), Ethacrynic acid (Edecrin), Furosemide (Lasix), Torsemide (Demadex), Candesartan and HCTZ (Atacand HCT), Chlorothiazide (Diuril), Chlorthalidone (Hygroton), Hydrochlorothiazide or HCTZ (Hydrodiuril), Methyclothiazide (Enduron), Metolazone (Zaroxolyn)

• Stimulants like Methylphenidate (Metadate, Ritalin)

• Cholesterol meds like Cholestyramine (Questran) and Colestipol (Colestid)

• Steroids like Betamethasone (Diprolene, Luxiq), Dexamethasone (Decadron), Hydrocortisone (Cortef), Methylprednisolone (Medrol), Mometasone (Elocon), Prednisolone (Pediapred Liquid), Prednisone (Deltasone, Liquid Pred, Sterapred), Triamcinolone (Aristocort cream), Flunisolide (Nasarel, Nasalide), Futicasone (Flonase), Triamcinolone (Azmacort inhaler)

• Hormone replacement (including some birth control) like Diethylstilbestrol (DES), Estradiol (Activella, Climara, Combipatch, Estrace, Estraderm, Estring, EstroGel, Femring, Menostar, and many others), Estrogen-containing drugs (hormone replacement therapy and birth control), Estrogens, conjugated (Premphase, Prempro), Estrogens, esterified (Estratab), Estropipate (Ogen), Ethinyl estradiol (found in many birth control pills), Levonorgstrel (found in many birth control pills)

• Immunesuppressants like Cyclosporine (Sandimmune, Neoral), Tacrolimus (Prograf)

• Aromatase inhibitors like Anastrozole (Arimidex)

• Osteoporosis meds like Raloxifene (Evista)

• SERMs (Selective Estrogen Receptor Modulators) like Raloxifene (Evista), Tamoxifen (Nolvadex), Toremifene (Fareston)

• Sulfonamides like Sulfa antibiotics, some diabetic medications