Thyroxine (T4) is the main hormone your thyroid makes. Your thyroid hormones are important because they control how your body uses energy from the food you eat. (Photo Credit: iStock/Getty Images) T4 ...

A chloride blood test, or serum chloride level, can be part of a comprehensive or basic metabolic panel. Some health conditions, including dehydration, can affect chloride levels. Chloride is an ...

The hemoglobin A1C test is a type of blood test. It provides information about your average blood sugar levels over the past two to three months. If you have type 2 diabetes, the test can help you ...

Brad Reisfeld is a professor of chemical and biological engineering, biomedical engineering, and public health at Colorado State University. Your blood serves numerous roles to maintain your health.

When you shop through retailer links on our site, we may earn affiliate commissions. 100% of the fees we collect are used to support our nonprofit mission. Learn more. If you're like most of my ...

Beth Skwarecki is Lifehacker’s Senior Health Editor and has been writing about health, fitness, and science here since 2015. Beth was the recipient of the 2017 Carnegie Science Award in science ...

Mark Gurarie is a writer covering health topics, technology, music, books, and culture. He also teaches health science and research writing at George Washington University's School of Medical and ...