Illustration: Mark Matcho

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Keep Your Heart Strong
Let's start with my favorite organ: the heart. We already know that sex can be a decent cardio workout (one 30-minute session can burn 70 calories); now research indicates it may protect your heart in other ways. A study in the Journal of Sex & Marital Therapy found that people who had sex an average of 12 times per month had greater heart rate variability (HRV)—a measure of how well the heart responds to subtle changes throughout the day (like standing versus sitting). Higher HRV is a good thing; it may lower your risk of developing heart disease, the leading cause of death for women.