Relationship between serum vitamin D and insulin resistance in normal weight and overweight or obese men.

Abstract

Obesity is a common clinical disorder featuring excessive buildup of body fat. The bioavailability of vitamin D in obese subjects is lowered because of its sequestration in the superfluous fat tissue. Hypovitaminosis D itself is associated with glucose intolerance, insulin resistance, dyslipidemia and hypertension, which are also linked to obesity. Objectives: To compare and correlate serum vitamin D and insulin resistance in controls and overweight / obese males. Study Design: Cross Sectional, Comparative Study. Setting: The study was conducted in the Department of Physiology, Post – Graduate Medical Institute (PGMI) in collaboration with Lahore General Hospital and Central Park Medical College. Period: From 7th June 2018 to 10th Oct 2018. Material and Methods: Eighty male subjects (age range 35-50 years) included in this cross-sectional comparative study were divided into two groups on the basis of BMI; Group I: non-obese (control) BMI < 25 Kg/m2 (n=40) and Group II: overweight / obese males with BMI ˃25 Kg/m2 (n=40). Fasting serum vitamin D (25 hydroxy cholecalciferol; 25-OH D, serum insulin and blood glucose levels were measured. Insulin resistance (IR) was estimated from fasting serum glucose levels taken in mmol/l and the fasting serum insulin taken in µIU/ml by using Homeostasis Model Assessment-estimated Insulin Resistance (HOMA-IR index). Results: Group II had lower serum 25-OH vitamin D levels and higher HOMA-IR index than control group. Significant negative correlation was present between serum vitamin D and HOMA-IR. Conclusion: Vitamin D deficiency may promote insulin resistance in overweight or obese individuals.

Knowledge, Attitude, and Practices Regarding Vitamin D in Middle-Aged Pakistani Population and the Impact of Sun Exposure on Their Serum Vitamin D Levels

“…Vitamin D, a fat-soluble secosteroid hormone, is a key contributor to musculoskeletal health through its role in calcium and phosphorus homeostasis [1]. Data accrued over the last two decades has shown that low vitamin D levels are associated with a wide range of clinical disorders such as immune dysfunction, cardiovascular diseases, autoimmunity, and neurological deficits, suggesting the involvement of vitamin D in multiple physiological processes [2].…”

Socio-Demographic and General Physical Risk Factors of Pre-Eclampsia in Pakistan

“…The patients also had reduced outdoor activity levels, which may be interpreted as less physical activity contributing to higher BMI. Outdoor sunlight exposure is also important for cutaneous vitamin D production, which is now known to modulate a wide 12,18 variety of systemic responses. These women are thus vulnerable to vitamin D deficiency which itself 19,20 has been linked with pre-eclampsia.…”

Association of vitamin D and magnesium with insulin sensitivity and their influence on glycemic control

“…In the Longitudinal Aging Study Amsterdam, a low 25(OH)D level was associated with the risk of metabolic syndrome[ 25 ]. Iqbal et al [ 26 ] proved that hypovitaminosis D, hyperinsulinism, and high homeostasis model assessment-estimated insulin resistance (HOMA-IR) index (indicating insulin resistance) are more prevalent in overweight and obese individuals.…”

“…On the other hand, Luay et al [ 49 ] conducted a double-blind placebo-controlled study among T1DM pediatric patients to assess for tight glycemic control and decrement in symptoms and signs of T1DM using vitamin D3 800 IU/d and magnesium 3 mg/kg/d for 180 d. They reported that the supplementation of both micronutrients was safe and effective in reducing the symptoms and signs of T1DM compared with those in the placebo group[ 49 ]. Both hypomagnesemia and hypovitaminosis D were also found to be inversely proportionate to triglyceride levels, thus highlighting their role as cardiometabolic risk factors[ 26 , 50 , 51 ].…”