Abstrak
Latar Belakang: Obesitas merupakan kondisi kelebihan lemak tubuh yang dapat menjadi faktor risiko gangguan metabolik seperti intoleransi glukosa dan pro inflamasi. Asupan diet yang baik berpengaruh terhadap kualitas diet yang dapat menurunkan risiko gangguan metabolik. Beberapa studi menyebutkan kadar magnesium rendah pada orang obesitas. Magnesium merupakan kofaktor berbagai enzim dalam metabolisme glukosa yang berperan dalam proses ambilan glukosa di otot dan juga sebagai antiinflamasi. Tujuan dari penelitian ini adalah menganalisis hubungan lemak tubuh dan kualitas diet dengan kadar magnesium serum dan glukosa darah puasa pada dewasa obesitas.     
Metode: Penelitian cross sectional pada 93 dewasa obesitas (IMT ?25kg/m2). Penentuan persen lemak tubuh dan level lemak viseral menggunakan metode Bioelectric Impedance Analysis (BIA), Tanita BC 541. Penilaian kualitas diet dengan Indeks Gizi Seimbang dianalisis dari hasil rata-rata food recall 2x24 jam. Pengukuran kadar magnesium serum menggunakan metode kalorimetri dan glukosa darah puasa dengan metode heksokinase. Analisis bivariat menggunakan uji korelasi Spearman dilanjutkan analisis multivariat regresi linier berganda dan logistik untuk mengetahui hubungan antara semua variabel independen dengan kadar magnesium serum dan kadar glukosa darah puasa dengan nilai p<0>Hasil: Sebagian besar responden adalah wanita dengan rata-rata usia 45 tahun. Rata-rata total lemak tubuh sebesar 41,52% termasuk kategori obesitas, sedangkan rata-rata lemak viseral 10,68 termasuk kategori tinggi. Total lemak tubuh (r= 0,076; p= 0,470), lemak viseral (r= 0,033; p= 0,753) dan kualitas diet (r= 0,065; p= 0,538) tidak berhubungan dengan kadar magnesium serum sebelum dan setelah dikendalikan dengan variabel prancu antara lain asupan energi, karbohidrat, protein, lemak, serat, magnesium dan aktifitas fisik. Adanya korelasi signifikan lemak viseral (r= 0,229; p= 0,027) dengan kadar glukosa darah puasa, sedangkan total lemak tubuh (r= -0,038; p= 0,718) dan kualitas diet (r= -0,042; p=0,689) tidak berkorelasi signifikan dengan kadar glukosa darah puasa pada dewasa obesitas. Level lemak viseral merupakan variabel yang paling berhubungan dengan kadar glukosa darah puasa setelah dikendalikan dengan variabel usia, asupan energi, karbohidrat dan lemak.   
Kesimpulan: Lemak viseral berhubungan signifikan dengan glukosa darah puasa pada dewasa obesitas usia 20-57 tahun. Total lemak tubuh dan kualitas diet tidak berhubungan dengan kadar magnesium pada dewasa obesitas usia 20-57 tahun.
Kata Kunci: Total lemak tubuh, lemak viseral, kualitas diet, magnesium serum, glukosa darah puasa
Abstract
Background: Obesity is a condition of excess body fat which can be a risk factor for metabolic disorders such as glucose intolerance and pro-inflammatory state. A good dietary intake affects diet quality which can reduce the risk of metabolic disorders. Some studies mention low magnesium levels in obese people. Magnesium is a cofactor of various enzymes in glucose metabolism which plays a role in the process of glucose uptake in muscles and also acts as an anti-inflammatory agent. The purpose of this study was to analyze the correlation among body fat and diet quality with serum magnesium levels and fasting blood glucose in obese adults.
Methods: The research was cross sectional studies conducted on 93 obese adults (BMI ?25kg / m2). The percentage of body fat and visceral fat level were determined using the Bioelectric Impedance Analysis (BIA) method, Tanita BC 541. The diet quality assessment based on Balanced Nutrition Index were analyzed from the mean result of 2x24 hour food recall. The measurement of serum magnesium using kalorimetri method and fasting blood glucose using hexokinase method. Bivariate analysis using Spearman correlation test and multivariate analysis using multiple linear and logistic regression were conducted to determine the correlation among all independent variables with serum magnesium levels and fasting blood glucose levels with p values <0>Result: Most respondents are women with an average age of 45 years. The average total body fat of 41.52% included in the obesity category, while the average visceral fat 10.68 was included in the high category. Total of body fat (r= 0.076; p= 0.470), visceral fat (r = 0.033; p = 0.753) and diet quality (r = 0.065; 0.538) were not related to serum magnesium levels before and after being controlled by intake of carbohydrate, protein, lipid, fiber, magnesium and physical activity. There was a significant correlation between visceral fat (r = 0.229; p = 0.027) and fasting blood glucose levels, but total body fat (r = -0.038; p = 0.718) and diet quality (r = -0.042; p = 0.689) was not correlated with fasting blood glucose in obese adult. Visceral fat is the variables associated with serum magnesium levels after being controlled by the variables age, energy, carbohydrate and fat intake. Coclusion: There are significant correlation between visceral fat and fasting blood glucose in obese adult 20-57 years old. Total body fat and diet quality were not related with serum magnesium level in obese adults 20-57 years old. 
Keyword: Total of body fat, visceral fat, diet quality, serum magnesium, fasting blood glucose.