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Type 2 diabetes is characterized by cellular and extracellular Mg depletion. Epidemiologic studies showed a high prevalence of hypomagnesaemia and lower intracellular Mg concentrations in diabetic subjects. Insulin and glucose are important regulators of Mg metabolism. Intracellular Mg plays a key role in regulating insulin action, insulin-mediated-glucose uptake and vascular tone. Reduced intracellular Mg concentrations result in a defective tyrosine-kinase activity, post-receptorial impairment in insulin action, and worsening of insulin resistance in diabetic patients. Mg deficit has been proposed as a possible underlying common mechanism of the "insulin resistance" of different metabolic conditions. Low dietary Mg intake is also related to the development of type 2 diabetes. Benefits of Mg supplementation on metabolic profile in diabetic subjects have been found in most, but not all clinical studies, and larger prospective studies are needed to support the potential role of dietary Mg supplementation as a possible public health strategy in diabetes risk.

Aging is very often associated with magnesium (Mg) deficit. Total plasma magnesium concentrations are remarkably constant in healthy subjects throughout life, while total body Mg and Mg in the intracellular compartment tend to decrease with age. Dietary Mg deficiencies are common in the elderly population. Other frequent causes of Mg deficits in the elderly include reduced Mg intestinal absorption, reduced Mg bone stores, and excess urinary loss. Secondary Mg deficit in aging may result from different conditions and diseases often observed in the elderly (i.e. insulin resistance and/or type 2 diabetes mellitus) and drugs (i.e. use of hypermagnesuric diuretics). Chronic Mg deficits have been linked to an increased risk of numerous preclinical and clinical outcomes, mostly observed in the elderly population, including hypertension, stroke, atherosclerosis, ischemic heart disease, cardiac arrhythmias, glucose intolerance, insulin resistance, type 2 diabetes mellitus, endothelial dysfunction, vascular remodeling, alterations in lipid metabolism, platelet aggregation/thrombosis, inflammation, oxidative stress, cardiovascular mortality, asthma, chronic fatigue, as well as depression and other neuropsychiatric disorders. Both aging and Mg deficiency have been associated to excessive production of oxygen-derived free radicals and lowgrade inflammation. Chronic inflammation and oxidative stress are also present in several age-related diseases, such as many vascular and metabolic conditions, as well as frailty, muscle loss and sarcopenia, and altered immune responses, among others. Mg deficit associated to aging may be at least one of the pathophysiological links that may help to explain the interactions between inflammation and oxidative stress with the aging process and many age-related diseases.

The aging of the world's population is a major contributor to the growing prevalence of the cardiometabolic syndrome (CMS) because older persons are more affected by the constellation of cardiovascular risk factors that constitute the syndrome. The prevalence of CMS has been related to the increasing prevalence of obesity, which is growing progressively even among older age groups. Indeed, obesity and aging are 2 overlapping mounting public health problems. It is currently accepted that CMS predicts cardiovascular mortality and/or the development of type 2 diabetes mellitus, and this is also true in studies including older persons. CMS is further complicated by modifications in body composition and fat redistribution during aging; older adults are at higher risk for developing central obesity and sarcopenia or sarcopenic obesity, a condition characterized by an important reduction in lean body mass associated with obesity, linked to an increased production of inflammatory adipokines that may alter insulin sensitivity and muscle mass and strength. A better understanding of the pathophysiologic mechanisms of sarcopenic obesity may help to elucidate the complex relationship between CMS and mortality/morbidity in older adults.

We examined whether adherence to a Mediterranean-style diet has positive effects on mobility assessed over a nine-year follow-up in a representative sample of older adults. This research is part of the InCHIANTI Study, a prospective population-based study of older persons in Tuscany, Italy. The sample for this analysis included 935 women and men aged 65 years and older. Adherence to the Mediterranean diet was assessed at baseline by the standard 10-unit Mediterranean diet score (MDS). Lower extremity function was measured at baseline, and at the 3, 6 and 9-year follow-up visits using the Short Physical Performance Battery (SPPB). At baseline, higher adherence to Mediterranean diet was associated with better lower body performance. Participants with higher adherence experienced less decline in SPPB score, which was of 0.9 points higher (p<.0001) at the 3-year-follow, 1.1 points higher (p= 0.0004) at the 6-year follow-up and 0.9 points higher (p= 0.04) at the 9-year follow-up compared to those with lower adherence. Among participants free of mobility disability at baseline, those with higher adherence had a lower risk (HR=0.71,95%CI=0.51–0.98, p=0.04) of developing new mobility disability. High adherence to a Mediterranean-style diet is associated with a slower decline of mobility over time in community dwelling older persons. If replicated, this observation is highly relevant in terms of public health.