Published: September 7, 2025
A Quick Note from Tamara Rubin:

The comparative chart of laboratory test results for various Magnesium supplement products we have tested and reported on to date is provided above. To see a close-up of the chart, just click on the image. For the full original lab reports for each product listed (as well as the full product name), please look at the numbered list of articles below. The numbers in the list below correlate with the numbers in the chart above.

Key Points of Interest in the Chart’s Data

• The only Magnesium product we have tested to date that came back as uncontaminated (with the low thresholds of detection for each of the metals we tested for noted in the chart above) is the CALM Magnesium Citrate Gummy product, linked here: https://amzn.to/41G7M7U
• We have not yet found an uncontaminated Magnesium Glycinate supplement (that came back from the lab with “non-detect” results for Lead, Cadmium, Mercury, and Arsenic — the four metals we test for).
• Given how heavily “Organics Ocean” markets the fact that it sells the cleanest products, its supplement ironically continues to be the most heavily Lead-contaminated Magnesium supplement we have tested to date.
• As expected, the Megafood Magnesium Capsule product tested positive for all four heavy metals we test for, including Mercury (their products appear to be consistently heavily contaminated with all four heavy metals).
  • Here are links to all the MegaFood Supplement Lab Reports we’ve published as part of the Lead Safe Mama, LLC Community Collaborative Laboratory Testing Initiative.
• The Pure Encapsulations magnesium product tested positive for Lead, which was not surprising to us, as all of the products we have tested from the brand have been positive for heavy metal contaminants.
  • Here are links to more Pure Encapsulations supplement lab reports we have published.
• Three lab reports for the products in the chart above have not yet been published.
• Please note the difference in Lead levels between the Doctor’s Best product in capsule form vs. the Doctor’s Best product in tablet form.
  • Based on all the supplements testing we have conducted to date, tablet-form supplements typically test positive for higher levels of contaminants than capsule-form supplements (with few exceptions).
  • We expect this is a result of the fillers and colorants used for tablet-form supplements (including Titanium Dioxide).
  • While we do not advocate for the use of (or recommend) any supplements, if you are going to take a supplement, we generally suggest considering products that come in a powder or liquid form to avoid additional contaminants that can be introduced with the capsule or tablet-form (the capsules themselves, veggie or otherwise, often introduce contaminants like Arsenic, and possibly traces of Lead and Cadmium, depending on the ingredients used to make them).

Help us test MORE Magnesium supplements!

Two of the campaigns to cover the costs of testing and reporting for the products shown in the chart above have not yet funded (our re-testing of the Doctor’s Best capsule product has also not yet funded). If you appreciate the information we are sharing here, and would like to make a contribution supporting this Magnesium testing project, (helping us be in a position to test more Magnesium products and seek safer choices) please contribute in one of the following four ways — thank you!

1. Fundraiser for Doctor’s Best Magnesium Tablets
2. Fundraiser for MegaFood Magnesium Capsules
3. The Lead Safe Mama, LLC General Fund GoFundMe
4. Join us on Patreon, either for free or with a small monthly gift in support of the work we do.

Articles with Lab Reports

Here are the links to all of the articles we have published to date, featuring lab reports for the Magnesium supplements included in the chart above (numbers in the list correspond to the numbers at the top of the chart above each product image):

1. Calm Magnesium Citrate Gummies
2. YouTheory Sleep Powder with Magnesium Citrate
3. Doctor’s Best Magnesium Lysinate Glycinate Veggie Capsules
4. Doctor’s Best Magnesium Lysinate Glycinate Veggie Capsules — RETEST — Not yet published
5. Pure Encapsulations Magnesium Glycinate Capsules
6. Genmedics Nutrition Magnesium Bisglycinate Capsules
7. MegaFood Magnesium Capsules, Glycinate, Malate, Citrate, — Not yet published
8. Doctor’s Best Magnesium Lysinate Glycinate Tablets — Not yet published
9. Organics Oceans Magnesium Glycinate + Low Dose Zinc

Some additional reading

• To see our full list of lab-tested safer choices, click here.
• For our landing page with links to the over 500 lab reports we have published since the beginning of the Lead Safe Mama, LLC Community-Collaborative Laboratory Testing Initiative (in March, 2024), click here.

For those new to the work of Lead Safe Mama, LLC

Tamara Rubin is a multiple-federal-award-winning independent advocate for childhood Lead poisoning prevention and consumer goods safety, and a documentary filmmaker. She is also a mother of Lead-poisoned children (two of her four sons were acutely Lead-poisoned in 2005).

• Tamara owns and runs Lead Safe Mama, LLC — a unique community collaborative woman-owned small business for childhood Lead poisoning prevention and consumer goods safety.
• Since July 2022, the work of Lead Safe Mama, LLC has been responsible for seven product recalls (FDA and CPSC).
• All test results reported on this website are science-based, accurate, and replicable.
• Please check out our press page for news coverage of our work here.

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