A major reason for low libido is stress. Stress can make sexual intercourse difficult for anyone. Eliminating the worry and anxiety in your life can make you a better sexual partner, and this is where the lemons come in. Lemons are a natural relief against stress. Adding a slice of lemon in a glass of water or a cup of tea will get rid of your worries, boost your energy and increase your sexual desire to spice things behind closed doors.