Thorne Magnesium Bisglycinate
Thorne Magnesium Bisglycinate is a powdered magnesium supplement that supports relaxation, muscle function, and healthy sleep. Each scoop provides 200 mg of magnesium in a well-absorbed form that's generally gentle on digestion.
When researching supplements, I look beyond the active ingredients. I consider sourcing, manufacturing practices, ingredient transparency, third-party testing for contaminants like heavy metals, and whether the dosage is appropriate. Thorne stands out for its simple formula, quality-control practices, and independent NSF Certified for Sport certification.
Ingredients
Active Ingredient: Magnesium (as magnesium bisglycinate), 200 mg per scoop.
Other Ingredients: Citric acid and monk fruit concentrate.
What I Like About It
Magnesium bisglycinate: A well-absorbed form of magnesium that's generally easier on digestion than magnesium oxide and less likely to cause loose stools.
Simple formula: No added sugar, artificial dyes, or undisclosed flavor blends.
NSF Certified for Sport: Independently certified through a program that includes label verification, screening for prohibited substances, and manufacturing-facility oversight.
Quality testing: Thorne reports testing for ingredient identity, potency, and contaminants, including heavy metals and harmful microbes.
A Closer Look at the Ingredients
Magnesium Bisglycinate: Magnesium plays an important role in nerve function, muscle relaxation, and normal sleep processes. This form is bound to glycine, an amino acid involved in nervous system function. Some human research has found modest improvements in sleep with magnesium supplementation, although it hasn't been proven to work better than every other form.
Things to Keep in Mind
Magnesium can cause digestive upset, especially at higher doses. People with kidney problems may have difficulty clearing excess magnesium from the body.
Magnesium can also interfere with the absorption of certain medications, including some antibiotics and osteoporosis medications.
The adult limit for magnesium from supplements and medications is 350 mg daily unless otherwise directed by a healthcare professional. This doesn't include magnesium naturally found in food.
Pregnancy & Breastfeeding: Magnesium is an essential nutrient, but a healthcare professional should review supplemental amounts.
Children: Children's magnesium needs and upper limits for supplements differ. This product is formulated for adults.
About the Brand
Thorne manufactures supplements with an emphasis on ingredient quality and testing. The company reports following current Good Manufacturing Practices (cGMP) and testing raw materials and finished products for identity, potency, and contaminants.
This product is also NSF Certified for Sport, which independently verifies specific quality standards.
Although Thorne reports extensive testing, I haven't reviewed a batch-specific certificate of analysis showing the exact levels of heavy metals or other contaminants in the finished product.