By Michael Roizen, MD, and Mehmet Oz, MD

Trying to make a baby? Well, even though the typical male body produces 12 million sperm a day, in a Harris Poll, two out of three men admitted they don’t do much -- if anything -- to support healthy male fertility. That needs to change. A growing stack of research shows that there’s plenty guys can do to ensure that their swimmers are plentiful, fast and equipped to get the job done. Now, you may need a fertility doc’s help if you two have been trying to get pregnant without success for more than a few months, but for most, everyday strategies can help.

Wear boxers during the day, sleep naked at night. For optimal sperm quality and quantity, your sperm-production factory needs temperatures cooler than the rest of your body. Tight underwear can damage sperm and reduce sperm count by up to 50 percent. In a year-long study of 500 guys, those who wore boxers during the day and nothing at night had 25 percent less DNA damage to their sperm than men who wore snug briefs ‘round the clock. 

Slather on a mineral-based sunscreen. Sun-protection products that use micronized zinc oxide or titanium dioxide to filter out the sun’s damaging ultraviolet rays are our first choice. That’s because sunscreens containing avobenzone, homosalate, meradimate, octisalate (also known as octyl salicylate), octinoxate (or octyl methoxycinnamate), octocrylene, oxybenzone (also called benzophenone-3 or BP-3) and padimate O may impair sperms’ ability to fertilize a human egg.

Cut back on caffeine. A study looking at miscarriage and health habits of women and men found that women drinking more than two caffeinated drinks a day in the weeks and months before trying to conceive, could raise odds for miscarriage. Coffee, tea, soda and other drinks with caffeine had an effect when either partner over-did it. For men, caffeine may reduce sperm count.

Up the Vitamins. Protect yourself by taking a daily multivitamin several months before you two try to conceive.  Zinc (about 12mg a day) and vitamin D3 (up to 1,000mg a day) keep sperm fast and healthy too. DHA omega-3 is important for both of you. (Women should also get 400 micrograms of folic acid daily to prevent spine defects.)

Relax! According to a Rutgers University study, feeling stressed-out could reduce sperm concentration and leave more sperm deformed or unable to complete their great race to the egg. Seems stress hormones can interfere with testosterone, crucial for healthy sperm.

Unplug your cell phone before you answer it. Guys who talked on their mobile phone while it was charging were four times more likely to have reduced sperm concentrations than those who unplugged their phones first, says a Israeli study. Carrying your phone near your groin could cause trouble, too, so stick it in your suit or sports jacket pocket.  

Skip the drinks and smokes. Tobacco use can slash sperm count. And having more than one drink per day could mess with the shape of sperm, a sign they may be damaged or unable to move quickly.

Work out while you watch TV. Guys viewing more than 20 hours of TV per week had sperm counts 50 percent lower than those who rarely watched, research shows. In contrast, getting plenty of vigorous exercise could increase sperm counts by as much as 73 percent -- a great reason to head to the gym and watch your favorite shows while you pump iron or hop on the treadmill.

Eat more of this, less of that. Fruit and veggies support the development of high-quality sperm; so does getting plenty of omega-3 fatty acids from sources like salmon, wild trout, sardines or anchovies. Saturated fat found in meats, dairy, processed snacks and desserts can slash sperm counts by 38 percent. Eating well and getting plenty of exercise will also help you maintain a healthy weight, another winning strategy for stronger, faster swimmers.