athletes but they're banned from the olympics. because they're men. we get in the water with britain's only male synchronized swim team. >> from the global resources of abc news, with terry moran, cynthia mcfadden and bill weir in new york city. this is "nightline." july 30th, 2012. good evening. i'm cynthia mcfadden. tonight, it's all over supermarket shelves, restaurant menus. and now the gluten-free diet is even making a splash at the olympic games. either by choice or necessity, several medal-winning champs have claimed that cutting out the gluten in everything from bread to pasta has helped their performance. does it make sense for you to try it too? here's my co-anchor terry moran with tonight's "you are what you eat." >> dana vollmer about to win her first olympic gold medal and trying to make it a world record as well! yes!

>> reporter: when dana vollmer won gold in the butterfly at the olympics, america cheered. one american with special enthusiasm. >> and congratulations to dana vollmer, by the way. she set a world record in butterfly and she happens to be gluten free. she's my gluten-free goddess with a gold medal in a world record, i love her. >> reporter: elisabeth hasselbeck of "the view," one of the most famous gluten free eaters in america, and she's got a new olympic hero. but dana vollmer isn't the only gluten-free olympian. there is tennis star novak djokovic after winning bronze in beijing, he's gluten-free. and another star, gluten free. lisbeth hasselbeck like millions more has celiac disease, a genetic disorder that makes a person intolerant to gluten. dana vollmer, like more and more peel, feels better when she stops eating foods containing gluten. what is gluten?

a protein found in wheat, rye, barley, and other grains, and many processed foods. soups, salad dressings, sauces, too. >> i think everybody should be off gluten. >> reporter: this doctor is a practitioner of a functional approach to healing, and a prophet of going gluten-free. >> most people, when they stop gluten, lose weight, are energized, aches and pains free up. they have more energy and they sleep better. it affects every system in the body. >> reporter: buffett doctor's biggest fans, tabatha coffey. >> i'm done. >> reporter: star of "tabatha takes over" on bravo. >> i am tabitha and i hate it when things give me a hard time. glueden was giving me a really hard time so i had to tell it to [ bleep ] off. >> reporter: lisbeth hasselbeck had to agree, a bit more demurly.

>> i feel like my name should be in here. i hang out here. >> reporter: we talked to her about shopping to avoid gluten, bread crumbs to cookies to bagels, it's there. pie crust is there. >> reporter: look around any grocery store and you see the booming gluten-free business. it's a multibillion dollar market now. and the champions of gluten-free living believe it should get a lot bigger. >> those who are adopting it for fashion or trend they are going to probably like it. they're going to see that there are many more options than they thought. >> reporter: do you think i'd be better off refuduce organize eliminating gluten from my duty? >> i think if you gave yourself a challenge where you went gluten-free, you'd find your energy levels would soar and you'd like how you felt every day. >> reporter: about 1 in 100 people are born with celiac disease. what about the rest of us? should everyone stop eating gluten?

>> yes. i'll go so far as to say the wheat of today is a food probably no one should eat. now, that is talking as a clinician, there is no research to back this up yet. >> reporter: that's right. there is no conclusive scientific research proving any benefit at all in a gluten-free diet for the vast majority of people. dr. peter green of columbia university is one of the world experts in celiac disease. he's spent a career freeding and studying the impact of gluten on the human body. are there benefits for a person who doesn't have celiac disease in adopting a gluten-free diet? >> not that i'm aware of. >> reporter: not only that, but there's no guarantee of weight loss and it might be bad for you to cut out all gluten. many doctors who are familiar with the duty say going gluten-free can be dangerous. i see famous people telling me it's a healthful way to eat.

it sounds healthy. what's wrong? >> yeah -- well, a gluten free diet is not entirely healthy. often, it lacks fiber. and the manufacturers of wheat flour fortify wheat flour with vitamins and minerals. >> reporter: this doctor and so many other scoff at the concerns of researchers and skeptical doctors. >> i've been doing this for long enough that i don't really care. why wouldn't i believe my patients telling me these things? i'm not at all surprised to hear these athletes are doing better when they get off gluten. >> reporter: the debate will continue. but for dana vollmer and others, it's settled. gluten free is golden. >> thanks to terry. next up, former vice president dick cheney tells us how his life was saved by surgery. then we hit the pool with the synchronized swim team barred from the olympics for being guys. ♪

♪ ♪ [ male announcer ] you've been years in the making. and there are many years ahead. join the millions of members who've chosen an aarp medicare supplement insurance plan insured by unitedhealthcare insurance company. go long.

"nightline" continues from new york city with cynthia mcfadden. he was one of the most controversial and powerful vice presidents in this country's history. dick cheney is a political lightning rod, loved by some, despised by others. he has lived through the last two years in limbo, slowly wasting away as he waited for a heart transplant. tonight, in a candid encounter, he tells it all to jonathan karl in a "nightline" interview. >> reporter: while we were walking with dick cheney in jackson hole, wyoming, we ran into a 12-year-old boy who was actually able to one-up the former vice president. >> hello, tommy, how are you?

tommy's had two heart transplants. >> i've had just one. you're ahead of me. it's miracle stuff, saved my life. >> reporter: the guy known as darth vader talked to us about facing his own death two years ago as his heart, after six heart attacks, started to fail for good. >> two years ago at this time i was on a respirator, heavily sedated. just had a pump, left ventricular, on my heart. it was the end. >> reporter: dick cheney like i'd never seen him before. reflecting on his own mortality, personal, even vulnerable. >> lost 40 pounds, heavily sedated in the intensive care unit. had pneumonia while i was in recovering from the surgery. and by the time i came out from under, looked in a mirror, and what i saw was my dad shortly before he died. >> reporter: back then, cheney looked like a shadow of his old self. today, he's transformed. thanks to an anonymous organ

donor. do you know anything about the donor? >> i don't. they deliberately maintain anonymity, at least at the outset. i can't think of a more magnificent gift than to be given additional years of life and that's what it is. >> reporter: don't think cheney's gone soft. when it comes to politics he's as confrontational as ever, even taking a shot at john mccain for choosing sarah palin as his running mate. >> i like governor palin. i've met her, i know her. attractive candidate. but based on her background, she'd only been a governor for two years, i don't think she passed that test. >> reporter: being ready? >> being ready to take over. and i think that was a mistake. >> reporter: and much harsher words for president obama. >> i think he's been one of our weakest presidents. i fundamentally disagree with him philosophically. i'd be hard-put to find any democratic president that i've disagreed with more than barack

obama. >> reporter: really? worse than jimmy carter, in your perspective? >> yes. >> reporter: it's cheney who's come under wire as architect of the iraq war but he accused obama of blowing it in the middle east. >> i think obama's made big mistakes. i look for example at the middle east situation today. it seems to be growing increasingly chaotic. we've got ongoing conflict in syria where thousands of people have died. there's continuing problems in iraq. i look at what the obama administration's done and it's basically head for the exits. with respect to afghanistan, you know, we're in a similar situation now. it's tough. it's hard. it's difficult. i know the public's tired of conflict. but if we turn our backs and walk away, we're just headed for trouble down the road eventually. and this administration is not in a position, frankly, to do anything about it because nobody trusts him. >> reporter: doesn't president obama deserve credit for the war on terror?

you've got 24 or so high-value targets taken out, bin laden's dead. you can't say he's been soft on terror, can you? >> i wouldn't say he's been soft on terror. he's made a number of mistakes. bin laden, fine. a lot of the intelligence that ultimately led to the capture came from programs we had in place in the bush administration. >> reporter: do you think you'll be going to the convention? >> no. >> reporter: no? >> i've got a fishing trip planned that week. >> reporter: dick cheney may have faced mortality but when it comes to his legacy there's been no change of heart. do you have any regrets? >> not really. >> reporter: really? you left office as one of the most unpopular vice presidents in modern times. i never worry about the polls. if i had, i was in the wrong line of work. >> reporter: for yate line jonathan karl in jackson hole, wyoming. thanks to jon karl. men in a women's world. an all-male synchronized swim

team fighting for the chance to compete. [ female announcer ] over the last ten years, your mouth has giggled, snuggled, bubbled ...and yellowed. because if you're not whitening, you're yellowing. crest whitestrips remove over ten years of stains and whiten 25 times better than a leading whitening toothpaste. crest 3d white whitestrips.

earlier tonight, 17-year-old american swimmer missy franklin took home olympic gold in the 100-meter backstroke. and teammate matt grevers also won the gold in the same men's race. this brings the total medal count to 17 for the americans, tied for the first place with china. not every athlete who dreams of olympic glory gets their chance. next we meet one team with an unusual problem. they can't even compete because -- they're guys.

we welcome to "nightline" julie sodi, correspondent for espn. julie is a two-time olympic medalist in soccer. she brings "faster, higher, weirder." >> reporter: at this pool in the heart of london a group of medal winning athletes is training for one of the most demanding of olympic sports, synchronized swimming. no matter how hard they train, no matter how good they are, these swimmers aren't welcome at these summer games. for one reason. they're guys. >> it's still the same old mindset. well, it's pretty, it's what girls do, blah, blah, blah. we can't to challenge that and say, no, boys can do this as well. >> reporter: they brought home the gold in some of the biggest international competitions. but because men are still barred from olympic synchronized swimming, they're on the sidelines of these summer games. they're not the first.

american kenyon smith, one of the best in the world, was blocked from beijing in '08. bill may, who won all sorts of awards with women, was kept away from athens in 2004. now these brits say, enough is enough. they've written a letter to the international olympic committee. they want the rules changed in time for rio in 2016. so far, they say there is no response. how ironic is it that this olympics seems to be all about equality, and women having the opportunity, and yet you guys are sitting here looking from the outside in? >> people say, oh, ha ha ha. the few people that have tried have commented on how hard it is. >> reporter: but esther williams made it look so easy in the movies. and on "saturday night live," martin short and harry sherer turned it into a big joke.

>> men's synchro isn't in the '88 olympics yet. >> that's okay because we could use the time. i'm not that strong of a swimmer. >> reporter: how do you get people to take men's synchronized swimming seriously? >> i ask people to come and try it out. >> reporter: if i did synchronized swimming, would i have a stomach that looks like that? >> maybe. >> reporter: never one to shy away from an olympic-sized challenge i decided to take the guys up on their offer. after all, i do have two olympic gold medals in my underwear drawer at home, and i like to think i'm still in pretty good shape. first, the guys have to show me the proper way to start our routine. and it doesn't take long for me to realize this is a lot tougher than it looks. >> one, two, three, four, five, six, seven, eight. >> reporter: that's their coach. a former yugoslav champion.

trying to whip me into shape. >> oh, fabulous! >> reporter: the moves they're teaching me involves six men who swim below me, lift me into the air, and i pull off an effortless flip. >> aahhh! >> reporter: or not. my first few are more like belly flops. then, my nose clip falls off. but despite the injury and after practice, i finally nail it. >> i managed to do one somersault, really, really good for a beginner. >> reporter: and my final challenge, the flamingo, just like in those old movies. i manage to impress with my sleek moves. but i must admit, by now i'm totally wiped out.

>> now we're talking. >> reporter: but somehow the guys are still kicking and they promise to keep pushing until men's synchronized swimming earns its place on the olympic medal stand. i played soccer growing up, right? i played in an era when women weren't playing that much. people would laugh at us, throw things at us when we'd go to brazil. how hard is that to keep growing and keep training? >> i figure, let the younger people come do this. encourage kids get involved in synchro, build up the talent. hope we'll see guys doing olympic-level synchro in a few years' time. >> reporter: first, my moment of truth. could this former olympic athlete swim on their level? >> do you think i could make the team? >> oh, yeah, definitely. >> yeah. >> i thought you were brilliant. definitely good enough to join us. >> reporter: for "nightline," i'm julie fouty in london. >> thanks to julie. and thank you for watching abc

news. good evening, this is our midnight mini cap. first, the day's top stories, 17-year-old enjoy facing attempted murder charges during an online game led to a vicious stabbing. he was accused of a deal to buy marijuana. the argument begin while playing video games online. the teen grabbed a rifle and his a knife and went to his home to confront him. >> he shot at my son. i went downstairs to call the police. he put his gun down and ran back upstairs. i thought they were fighting and