Which lifestyle factors change SHBG?

SHBG (sex hormone-binding globulin) is modulated by several lifestyle factors, with evidence coming mainly from observational studies and smaller interventions. High body fat, especially visceral fat, lowers SHBG – likely via insulin resistance and inflammation. Conversely, weight loss (especially through calorie restriction) raises SHBG. Diet matters: high-protein, low-glycemic, moderate-fat diets (e.g., Mediterranean) are linked to higher SHBG. Fiber and certain phytonutrients (e.g., lignans) may also help. Physical activity shows a positive but modest effect, particularly endurance training. Alcohol consumption lowers SHBG dose-dependently, while smoking tends to increase it. Chronic stress and poor sleep can negatively affect SHBG via cortisol and insulin. Importantly, effects are often small and individually variable. SHBG is not an isolated marker; it should be interpreted alongside hormones, metabolism, and clinical symptoms. Supplements like vitamin D or magnesium have no proven effect on SHBG. The evidence is moderate – many studies are associative, not causal.