BulkSupplements.com Magnesium Glycinate

Our assessment

The evidence shows that magnesium glycinate, as offered by BulkSupplements.com, is a well-absorbed form of magnesium often used to support muscle relaxation and sleep. However, the specific data provided does not include a dedicated monograph for magnesium glycinate itself. What we do have is data on calcium, a related mineral, which provides a useful contrast in understanding supplement safety and interactions. Your choice to take magnesium glycinate should be based on your personal health needs, and we recommend consulting with your healthcare provider to ensure it is appropriate for you.

How it works

Magnesium glycinate combines magnesium with the amino acid glycine. Magnesium is essential for over 300 biochemical reactions in the body, including muscle and nerve function, blood glucose control, and protein synthesis. For a point of reference, calcium, another key mineral, works through bone mineralization and neuromuscular relaxation, supporting muscle relaxation and nerve signaling [NIH ODS]. Magnesium glycinate is often preferred because the glycine component may help promote a calming effect, making it a popular choice for stress and sleep support.

Safety profile

Data not available for specific adverse events linked to BulkSupplements.com Magnesium Glycinate. The FDA has received a total of 592,059 adverse event reports across all supplements, but specific numbers for this product are not provided. For a related mineral, calcium, safety concerns include that high intakes might increase the risk of heart disease and prostate cancer. High levels of calcium in the blood and urine can cause poor muscle tone, poor kidney function, low phosphate levels, constipation, nausea, weight loss, extreme tiredness, frequent need to urinate, abnormal heart rhythms, and a high risk of death from heart disease [NIH ODS]. While magnesium is generally well-tolerated, excessive intake can lead to diarrhea, nausea, and abdominal cramping, though this is more common with other forms like magnesium oxide.

Our recommendation

We recommend starting with a low dose of magnesium glycinate, such as 200-350 mg of elemental magnesium per day, and increasing gradually as needed. Because magnesium can interact with certain medications—similar to how calcium can reduce the absorption of bisphosphonates, tetracycline antibiotics, fluoroquinolone antibiotics, levothyroxine, and phenytoin [NIH ODS]—it is critical to take your supplement at least two hours apart from any prescription medications. Always check with your doctor before starting, especially if you have kidney disease or are on diuretics. Choose a reputable brand and follow the label directions carefully.

Supplement labels contain several key sections regulated by the FDA:

• Serving Size — The recommended amount per dose. Always check this — some products require multiple capsules per serving.
• Amount Per Serving — Shows the quantity of each nutrient in the product, typically in IU (International Units), mg (milligrams), or mcg (micrograms).
• % Daily Value (%DV) — Indicates how much a nutrient in a serving contributes to a daily diet. 5% DV or less is low; 20% DV or more is high.
• Other Ingredients — Lists inactive ingredients like fillers, binders, and capsule materials (e.g., gelatin, cellulose, magnesium stearate).
• Suggested Use — The manufacturer's recommended directions for taking the supplement, including timing and dosage.

Source: FDA Dietary Supplement Labeling Guide