There's plenty of information (official and anecdotal) about the wax and wane of female hormone levels throughout the month. But did you know that men's hormones rise and fall each month, too? These 30-day hormone cycles are still a controversial topic within the medical community, largely because there's not a lot of data to back up the idea. Still, it makes sense to many people that men probably experience monthly hormonal ups and downs that affects mood and energy levels. After all, there are seasonal, daily and even hourly deviations in hormone levels. Testosterone quantities can range up and down four or five times an hour, and are typically higher in the morning and lower at night. For many men, testosterone levels follow a seasonal pattern, too: They are increased in the fall and decreased in the spring. [source: Diamond]. Keeping track of mood fluctuations for 30 days will likely reveal an emotional pattern prompted by hormones; simply understanding what's behind one's attitude can make a big difference in daily interactions, as you'll read on the next page.