Plasma and erythrocyte magnesium levels: from validation of the method to analysis in volunteers diagnosed to migraine

Deficiency of serum magnesium is associated with the incidence of migraine attacks. The present study aimed to evaluate plasma and erythrocyte magnesium levels in a group of patients diagnosed with migraine. Human donors were selected from basic health units (migraine, n = 25) and from a collection and transfusion unit (control, n = 25), both located in the city of Sinop, Brazil. Plasma and erythrocyte magnesium were assessed using flame atomic absorption. Plasma magnesium concentration was significantly lower in the migraine group (0.172 ± 0.018) compared to the control group (0.197 ± 0.020 mg/L), and erythrocyte magnesium concentration was also lower in the migraine group (0.393 ± 0.053 mg/L) compared to the control group (0.432 ± 0.056 mg/L). The method for analysis of magnesium in human plasma and erythrocytes by flame atomic absorption was shown to be in accordance with validation guidelines. This study shows that plasma and erythrocyte magnesium levels were significantly lower in volunteers diagnosed with migraine compared to healthy volunteers. Furthermore, erythrocyte magnesium proved to be a better marker than plasma magnesium for patients with migraine.

Perspective: The Case for an Evidence-Based Reference Interval for Serum Magnesium: The Time Has Come

The 2015 Dietary Guidelines Advisory Committee indicated that magnesium was a shortfall nutrient that was underconsumed relative to the Estimated Average Requirement (EAR) for many Americans. Approximately 50% of Americans consume less than the EAR for magnesium, and some age groups consume substantially less. A growing body of literature from animal, epidemiologic, and clinical studies has demonstrated a varied pathologic role for magnesium deficiency that includes electrolyte, neurologic, musculoskeletal, and inflammatory disorders; osteoporosis; hypertension; cardiovascular diseases; metabolic syndrome; and diabetes. Studies have also demonstrated that magnesium deficiency is associated with several chronic diseases and that a reduced risk of these diseases is observed with higher magnesium intake or supplementation. Subclinical magnesium deficiency can exist despite the presentation of a normal status as defined within the current serum magnesium reference interval of 0.75-0.95 mmol/L. This reference interval was derived from data from NHANES I (1974), which was based on the distribution of serum magnesium in a normal population rather than clinical outcomes. What is needed is an evidenced-based serum magnesium reference interval that reflects optimal health and the current food environment and population. We present herein data from an array of scientific studies to support the perspective that subclinical deficiencies in magnesium exist, that they contribute to several chronic diseases, and that adopting a revised serum magnesium reference interval would improve clinical care and public health.

Optimal Dietary and Plasma Magnesium Statuses Depend on Dietary Quality for a Reduction in the Risk of All-Cause Mortality in Older Adults

The association between dietary or plasma magnesium (Mg) with diabetes incidence and with mortality in free-living elderly was investigated. A total of 1400 participants from the Taiwanese Nutrition Survey, aged ≥ 65 years, and diabetes-free from the 1999–2000 were assessed. The dietary intake and plasma Mg concentration were obtained through 24h dietary recall and health examination at baseline. Participants were classified by quartiles (Q) of dietary Mg or by the plasma Mg normal range (0.75–0.95 mmol/L). Dietary diversity score (DDS, range 1–6) represented the dietary quality. During 8 and 10 years, 231 incident diabetes cases and 475 deaths were identified. Cox’s proportional-hazards regression was used to evaluate the association between Mg and health outcomes. The hazard ratios (95% confidence interval) for death in Q2 and Q3 of Mg intakes with DDS > 4 were 0.57 (0.44–0.74) and 0.59 (0.39–0.88), respectively, compared with the lowest intake and DDS ≤ 4 participants. Participants with normal and high plasma Mg in conjunction with high DDS had relative risks of 0.58 (0.37–0.89) and 0.46 (0.25–0.85) in mortality compared with low plasma Mg and lower DDS. Optimal dietary Mg intake and plasma Mg depend on dietary quality to reduce the mortality risk in older adults.