Intestinal Absorption and Factors Influencing Bioavailability of Magnesium-An Update.
Level 5 - mechanism / opinion, no new human data
Narrative review of mechanisms and dietary factors without systematic search or meta-analysis
PubMed 29123461 · doi:10.2174/1573401313666170427162740
What was done
This was a narrative review evaluating existing literature on the mechanisms of intestinal magnesium absorption (passive paracellular transport and active transcellular TRPM6/7 channels) and dietary factors influencing its bioavailability.
What was found
The abstract reports no numerical data or statistical comparisons. It reports that fractional magnesium absorption is higher with divided low doses throughout the day than a single large dose. Uptake is enhanced by proteins, medium-chain triglycerides, and low- or indigestible carbohydrates (e.g., resistant starch, inulin, mannitol), and impaired by phytate, oxalate, non-fermentable/partly fermentable fibers, and high doses of other minerals. Differences in bioavailability between organic and inorganic magnesium salts were inconsistent across studies.
Why it matters
It highlights that dosing patterns and overall dietary context are more critical determinants of magnesium uptake than the specific supplemental salt form chosen.
Limits
This is an unsystematic narrative review with no quantitative effect sizes or formal study quality assessments provided in the abstract. The authors note an absence of standardized testing methods for assessing magnesium status and intestinal absorption in humans.
Cited by
- contradicts Magnesium glycinate is the easiest form of magnesium to absorb for most people.