Effects of IGF1 rs6214 Polymorphism and Milk Consumption on Serum Levels of IGF-1 and GH and Body Composition.

Milk and dairy are rich in insulin-like growth factor 1 (IGF-1), a protein secreted through the action of growth hormone (GH) and implicated in growth and metabolism. OBJECTIVE: This study aimed to investigate the roles of milk intake and body composition and identify the presence of the single nucleotide variant (SNV) rs6214 in the insulin-like growth factor 1 gene (IGF1) and its effects on the serum IGF-1 and GH levels and body composition. METHODS: We analyzed 110 volunteers with and without a history of milk intake. Through a case-control study with one hundred ten healthy volunteers, serum IGF-1 and GH levels were measured using the ELISA technique, the body composition was determined with bio-electrical impedance equipment, genotyping of the rs6214 SNV was carried out using real-time PCR, and a dietary questionnaire was administered to assess milk intake, with or without consumption. RESULTS: The results showed that the highest levels of IGF-1 were found in people who regularly consumed milk, along with a lower body mass index (BMI) and percentage of fat. A lower BMI and fat percentage were associated with higher levels of IGF-1, lean mass, and SNV presence. Lower levels of BMI and percentages of subcutaneous and visceral fat were found in regular milk consumers. CONCLUSIONS: Our study suggests that dairy intake and the IGF1 gene rs6214 SNV are associated with higher levels of IGF-1, high levels of lean mass, a low BMI, a low % fat, and low visceral fat.