Unless you eat tofu with a shovel, soy poses no credible threat to your manhood. Rumors that isoflavones, the "active ingredient" in soy, have the potential to cause feminization in men—à la erectile dysfunction, lower sperm counts, and man mammaries—have been floating around for years but with essentially no hard evidence. Studies suggesting the link have been inconclusive at best. A recent large, peer-audited review of available studies, published in May in the journal Fertility and Sterility, concluded that soy does not cause feminization (though its author did have ties to the soy industry). With soy, we're sure of one thing: It's an excellent source of low-fat, lactose-free protein for athletes, and its isoflavones help protect against problems like cancer, hypertension, and heart disease (to name a few). Since there are no studies of guys who, say, drink a tanker of soy milk, just consume it in moderation—say, two to four servings of tofu per day—and you won't need to worry about a jog bra.
SWEET 'N' SLOW
A new class of sports drinks is emerging as a go-to source of fuel before you even begin to sweat. EAS's Peak ($3.50; eas.com) and Gatorade's Prime 01 ($1.30; gatorade.com) top off your energy stores with a slow-digesting sugar, called isomaltulose, that will still be giving you a trickle charge after two to three hours—much longer than the sugars in traditional sports drinks.
Support Outside Online
Our mission to inspire readers to get outside has never been more critical. In recent years, Outside Online has reported on groundbreaking research linking time in nature to improved mental and physical health, and we’ve kept you informed about the unprecedented threats to America’s public lands. Our rigorous coverage helps spark important debates about wellness and travel and adventure, and it provides readers an accessible gateway to new outdoor passions. Time outside is essential—and we can help you make the most of it. Making a financial contribution to Outside Online only takes a few minutes and will ensure we can continue supplying the trailblazing, informative journalism that readers like you depend on. We hope you’ll support us. Thank you.