Thorne Magnesium Citrate

Our assessment

The evidence shows that Thorne Magnesium Citrate provides a well-absorbed form of magnesium, a mineral essential for over 300 biochemical reactions in the body. For most adults, meeting the RDA of 310–420 mg daily can be challenging through diet alone, making this supplement a practical option [NIH ODS]. Data not available on specific clinical trials for this exact brand product.

How it works

Think of magnesium as a cellular gatekeeper — it helps regulate muscle and nerve function, supports a steady heartbeat, and contributes to bone structure [NIH ODS]. The citrate form is bound to citric acid, which may enhance absorption compared to other forms like magnesium oxide [NIH DSLD].

Safety profile

FDA received 694 adverse event reports for magnesium products overall. Side effects include diarrhea and gastrointestinal upset at high doses [FDA data]. Data not available on specific report counts for Thorne Magnesium Citrate alone.

Our recommendation

Start with one capsule daily with a meal to assess tolerance. Be aware that doses exceeding 350 mg from supplements can cause loose stools [NIH ODS]. If you have kidney issues, consult your doctor before use [NIH DSLD].

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