Magnesium oxide is (surpringly) better than citrate – RCT March 2012

Comparison of magnesium status using X-ray dispersion analysis following magnesium oxide and magnesium citrate treatment of healthy subjects.

Magnes Res. 2012 Mar 1;25(1):28-39. doi: 10.1684/mrh.2012.0305.
Shechter M, Saad T, Shechter A, Koren-Morag N, Silver BB, Matetzky S.
Leviev Heart Center, Chaim Sheba Medical Center, Tel Hashomer, Israel. shechtes at netvision.net.il

The magnesium content in food consumed in the Western world is steadily decreasing. Hypomagnesemia is associated with increased incidence of diabetes mellitus, metabolic syndrome, all-cause and coronary artery disease mortality. We investigated the impact of supplemental oral magnesium citrate versus magnesium oxide on intracellular magnesium levels ([Mg2+]i) and platelet function in healthy subjects with no apparent heart disease.

In a randomized, prospective, double-blind, crossover study, 41 (20 women) healthy volunteers [mean age 53±8 (range 31-75) years] received either magnesium oxide monohydrate tablets (520 mg/day of elemental magnesium) or magnesium citrate tablets (295.8 mg/day of elemental magnesium) for one month (phase 1), followed by a four-week wash-out period, and then crossover treatment for one month (phase 2).

[Mg2+]i was assessed from sublingual cells through x-ray dispersion (normal values 37.9±4.0 mEq/L), serum magnesium levels, platelet aggregation, and quality-of-life questionnaires were assessed before and after each phase.

Oral magnesium oxide, rather than magnesium citrate, significantly increased [Mg2+]i (34.4±3 versus 36.3±2 mEq/L, p<0.001 and 34.7±2 versus 35.4±2 mEq/L, p=0.097; respectively), reduced total cholesterol (201±37 versus 186±27 mg/dL, p=0.016 and 187±28 versus 187±25 mg/dL, p=0.978; respectively) and low-density lipoprotein (LDL) cholesterol (128±22 versus 120±25 mg/dL, p=0.042 and 120±23 versus 121±22 mg/dL, p=0.622; respectively).

Noteworthy is that both treatments significantly reduced epinephrine-induced platelet aggregation (78.9±16% versus 71.7±23%, p=0.013 and 81.3±15% versus 73.3±23%, p=0.036; respectively).

Thus, oral magnesium oxide treatment significantly improved [Mg2+]i, total and LDL cholesterol compared with magnesium citrate, while both treatments similarly inhibited platelet aggregation in healthy subjects with no apparent heart disease.

PMID: 22433473

Clinical Trial from which this paper was published

Clipped from PDF

Discussion

To the best of our knowledge, this is the first study to compare and contrast the impact of oral magnesium oxide and citrate on [Mg2+]i, demonstrating that a 30-day regime of oral Magnox supplement significantly increases [Mg2+]i compared to Diasporal in the same apparently healthy volunteers without CAD. Although our study participants were considered to be "healthy", their baseline [Mg2+]i was relatively low, reflecting a typical Western diet [1, 21], which portends a steadily decreasing amount of magnesium. Data show that the average daily intake of magnesium at the beginning of the 20th century was
410 mg while today it is only 200-300 mg. The rationale behind such reduced mineral consumption, including magnesium, in the contemporary diet is mainly due to industrial food processing and the over-utilization of fields designated for cultivating agricultural produce [21]. The current daily Recommended Dietary Allowance for magnesium is 420 mg for males and 320 mg for females above 31 years, and in stressful situations such as in pregnancy or physical growth, an additional 300 mg daily is recommended. Data from the 1999-2000 National Health and Nutrition Examination Survey suggest that a substantial number of adults in the United States fail to consume recommended daily amounts of magnesium. The diets of adult male and female Caucasians contain significantly more magnesium than those of African-Americans. Magnesium intake is lower among older adults in every racial and ethnic group worldwide. The intake of magnesium is significantly higher among African-American men and male and female Caucasians who take dietary supplements, compared with those who do not. In a population-based study of 30-year-old Israelis, about 60% had a magnesium deficiency [1, 21, 29-33].

Summary of side effects

Side Effect	Oxide baseline	Oxide 30 day	Citrate baseline	Citrate 30 day
None	42%	42%	60%	40%
Mild	53%	50%	35%	42%
Moderate	0	3%	5%	3%
Severe	0	0	0	0

Did the current medication improve your condition?

	Oxide	Citrate
No	5%	0
Yes	42%	25%
Same	48%	42%
Worse	8%	25%

Type	Elemental Mg	Increase in Mg ion
Mg Oxide	520 milligrams	2 mEq/L
Mg Citrate	300 milligrams	0.7 mEq/L

Mg Citrate: three times a day
Relative bioavailability = 2/0.7 *(300/500) = 1.7

See also VitaminDWiki: conflict with this study

• Magnesium Bioavailability - 2005
• Magnesium sources: Oxide thru Pico - March 2013 Mg Oxide only 4% bio-available
• Overview Magnesium and vitamin D
• All items in category Magnesium 365 items
• Magnesium L-Threonate – perhaps more bioavailable – Jan 2012