Long-Term Hormone Therapy Impacts Transgender Body Composition and Cardiovascular Risks

A new study from **Karolinska Institutet**, published in the Journal of Internal Medicine, examines the long-term effects of sex hormone treatment on body composition and cardiovascular risks in transgender individuals. The research involved MRI scans and metabolic testing of 17 transgender men and 16 transgender women undergoing testosterone and estrogen therapy, respectively. **Remarkably, transgender men experienced a 21% increase in muscle volume and a 70% increase in abdominal fat over six years**, alongside higher liver fat and LDL cholesterol levels, which raise cardiovascular disease risks. Changes in muscle mass and strength were most significant in the first year, with fat volume alterations continuing over time. Transgender women showed a 7% decrease in muscle volume after five years but stable muscle strength and increased total fat volume with less abdominal fat. The study highlights the need for ongoing health monitoring in transgender individuals to prevent cardiovascular and other health issues. **This research also enhances understanding of the masculinizing and feminizing effects of hormone treatment, emphasizing moderate expectations for long-term changes.** Future analyses will involve tissue samples to explore the interactions between genetic sex and hormone therapy effects.