dr. jon lapook is us with. jon, why is this? >> reporter: anthony, there are some theories.ause some thinning of the blood, so it can decrease blood clotting within the blood vessels. it also can be an antioxidant, anti-inflammatory and help ct dhow prevent direct damage to ine blood vessels. but in large amounts alcohol can be toxic to the muscle of the heart. >> mason: so what about heavier drinkers, jon? oneeporter: one of the things that's so good about this study is they defined what heavy drinking was. i once had a teacher who said a heavy come user is someone who drinks more than their doctor. that's not helpful. a heavy user in women is more than seven drinks a week and in men it's more than 14 drinks a week. in men that was linked to an g the sed risk of dying or getting cancer during the study period. remember, that one drink can in some people lead the five drinks or more and, of course, we all know the ravages that alcohol now,e has led to in our society. >> mason: but in general one drink with dinner is okay now, maybe even better than okay. dr. jon lapook, than

dr. jon lapook is following. this jon?>> reporter: anthony, for the longest time medical science has been grappling with how to prevent genetic knew -- knew tiggss and the terrible illnesses that come with them from being passed on generation to generation. the d.n.a. in this chromosome had a gene that causes a severe heart problem. so researchers used a special technique called crispr to find and remove the gene inside the fertilized egg. it's like finding a needle in a haystack. the cell then repaired itself, and at the end of the process, the gene that causes the heart defect was gone. that means theoretically the embryo could develop without the defect, but anthony, the f.d.a. prohibits the use of this technology to help achieve a human pregnancy. >> mason: jon, i know this technology is still in its infancy, but this raises serious ethical concern, doesn't it? >> john: huge ethical concerns. we've been thinking about this for decades, wow, you can repair a gene, but think about it. what are the unintended consequence,

dr. jon lapook.y much. >> up next, a toast to fleetwood mac. >>> we end with one of rock's most successful bands who took the stage for the first time 50 years ago last night. ♪ ♪ over the past half century they have sold more than 100 million records. but fleetwood mac first came together one august afternoon in england in 1967. so this was literally the first show you played together as a band? >> yep, number one. windsor jazz festival. >> drummer mick fleetwood looks back in his book "love that burns." >> we thought this was a very large p.a. system. [ laughter ] ♪ got a black magic woman >> reporter: their first hit "black magic woman" was written by peter green who left suddenly in 1970. >> when we lost peter green we were devastated. as people and our music. what are we going to do? >> reporter: they regrouped. and after bassist john mcvie married christine mcvie. she was brought into the band. ♪ it gets stronger every day >> christine just sort of fit? >> yeah. >> done. done. >> that simple --

dr. jon lapook on why stroke rates are falling for >> never thought it would be something that would happen to me. >> mason: and the know what who said, "make you

dr. jon lapook, cbs news, new york. >> ninan: we'll be right back. >> ninan: millions are making plans toch the total solar eclipse on august 21. john blackstone says to safely witness the spectacle, you'll need proper spect celz. >> reporter: with excitement building, eclipse glasses are going fast. >> and when you put these glasses on, then although you can't see anything else, the sun becomes watchable. >> reporter: astronomy professor andrew fraknoi. >> a typical sunny day, nobody is dumb enough to be staring at the sun. but sometimes during eclipses, your astronomical enthusiasm can overwhelm your common sense. >> you have to have the eclipse glasses so you don't burn your retinas. >> reporter: mark margolis' company, rainbow symphony, has made tens of millions safety approved shades. >> they are iso certified. >> reporter: you can't see anything through these. with so much demand, there are warnings of dangerous counterfeit eclipse glasses flooding the market online. nasa has a link to a list of reputable vendors selling clafts certified by the ison, "international standards organiz

dr. jon lapook on why stroke rates are falling for men but not women. >> never thought it would be somethinghat would happen to me. >> mason: and the know what who said, "make your

dr. jon lapook tells us it's being used to help alzheimer's patients. ♪ ♪ >> reporter: each week, the d.j but goodies at the todt hill senior center on staten island. also taking a spin-- 74-year-old carol daly, who was diagnosed with alzheimer's 12 years ago. we've been following carol and her husband, mike, since 2008. >> me and my husband, mike. >> reporter: charting her decline. what's your husband's name? >> my husband's? >> reporter: your husband's name. witnessing their love story. when we met again this spring, carol was barely talking. i really see a tremendous difference. >> uh-huh. >> reporter: in carol. what do you see? >> sadness. this is what we live so long for? >> reporter: caregivers like mike daly are desperate for anything that can improve quality of life. so we introduced the daly's to the music and memory program, created by social worker dan cohen. >> senses-- sight, smell-- really light up a very small part of the brain, but music lights up many parts of the brain. so even though the brain may deteriorate in certain areas, other areas the brain is still very much th

dr. jon lapook here to explain. jon. >> anthony, the study looks at rapid eye movement sleep, rem, the time you dream. there are four stages in the sleep cycle. stage one, sleep is light. it progresses to deep sleep in stage three. after that, there is rem sleep which usually occurs, four to five times over eight hours as your sleep cycle repeats. in this study, as the the amount of rem sleep declined, the risk of dementia increased. >> what might sleep have to do with dementia, john? >> anthony, the study was done people over 60. increasing evidence that toxins accumulate in the brain during the day. as you are awake. what happens at night, or whenever you sleep is that those toxins get cleaned out. something of a, garbage collecting fun tgcollect ing function. and include amaloid linto alzheimers. don't know when in the sleep cycle it occurs. very exciting research. >> does this mean sleep depravation can cause dementia? >> we don't know that yet. this is very exciting. because we know that the changes that occur i

dr. jon lapook. good morning. >> good morning. >> what is causing this to rise in men and women?e's simple called the microbium which includes the bacteria in our guts. 1,000 to 2,000 species is going on. if it gets out of balance, certain species may increase the risk >> wow. you're saying we don't understand why race may be a factor. >> yeah. and i want to make sure. there's been some confusion about this. year to year more die. >> kwhie is that? >> we don't know. a different psychological disease. you tend to get them at an earlier age and they tend to be more deadly and more advanced when they are discover. that's why the american college of gastroenterology suggests screening suggests at 50 to start at 45 in african-americans. >> 45 now. >> in african-americans. >> and how often should you do that? >> if you're at average risk, every ten years, a polyp, every difficult polyp, probably more than that. >> does diet make a difference? >> there is. red meats, people who don't exercise, diabetes, you want to be the right weight. there are things you can do. this in our control in

dr. jon lapook tells us it's being used to help alzheimers patients. >> each week the dj spins oldies butthe senior center on staten island. also taking a spin, 74-year-old carol daly. who was diagnosed with alzheimers 12 years ago. we have been following carol and mike. charting her decline. >> what's your husband's name? >> my husband's? >> your husband's name. >> yeah. >> witnessing their love story. when we met again this spring, carol was barely talking. i really see a tremendous difference in carol. >> what do you see? what do you see? sadness. this is what we lived so long for. >> care givers like mike daly are desperate for anything to improve quality of life. we introduced the dalys to a program create by social worker dan cohen. >> my sense is sight, smell. light up a small part of the brain. though the brain may deteriorate in certain areas. other areas of the brain are very much there. he started handing out ipods to nursing home residents. cobble hill health center in brooklyn one of the first to give it a try. decade later, in some 4500 sites. the headphones help eliminate d

dr. jon lapook is following this. jon?as been grappling with how to prevent again itting mutations and illnesses that come from them being passed down jen ration to generation. the dna in the chromosome had a gene that causes a severe heart problem. technique called crisper to find and help remove the gene inside a fertilized human egg. lying finding a needle in a hey stack. the cell then repaired itself and at the end of the process, the gene that causes the heart defect was gone. that means theoretically the embryo could develop without the defect. anthony the fda prohibits the use of the technology to help achieve a human pregnancy. >> i know this technology is in its infancy. this raises serious ethical concerns doesn't it? >> huge ethical concerns. been thinking of this decade. in medical school, wow, repair a gene. think about it. what are unintended consequences? who is to stay which genes if any should be repaired. what is a defect? you know, overall the big question is, do we have the wisdom to use this new techno

dr. jon lapook to look night. >> reporter: in 2013, diana hardiman was 30 years old, a vegetarian, a nonspokernd the picture of health. until, she had a stroke. >> the paralysis ended up seeping down from my arm to my leg. leaving the whole right side of my body, basically immobile. i thought, maybe i am becoming pair liesed. or, potentially, seeing death. >> reporter: that had to be terrifying for you? >> it was terrifying. >> reporter: hardiman is an example of a troubling fund. from 1999 to 2005, the incidence of stroke declined in men and from 2005 to 2010, while the rates among men continued to drop, they stayed the same for women. and women's hospital, says risk factors for stroke, obesity, high blood pressure and irregular heartbeat and diabetes may for some reason affect women differently than men. >> diabetes is a strong risk factor for stroke in both men and women. but in women, the risk is 26% higher than in men with diabetes. >> hardiman recovered and went back to her gourmet ice cream business in brooklyn. last june she had a second stroke. >> i had to stop being ceo of my ice cre

dr. jon lapook takes a look. >> she was 30 years old, a vegetarian, nonsmoker, surfer, and picture of health up till she had a stroke. >> the paralysis ended up seeping down from my arm to my leg leaving the whole right side of my body basically immobile. i thought maybe i'm becoming paralyzed or potentially seeing death. >> that had to be a terrifying feel. >> it was terrifying. >> hardeman is an example of a puzzling and concerning trend. this week's 1999 to 2005 it declined in men. while they continued to drop for men, they stayed the same for women. dr. katherine rexroad from briggman hospital says risk factors such as obesity, high blood pressure and irregularity heart beat may for some reason affect women different than men. >> diabetes is a strong risk factor for stroke in men and women but for women it's 26% higher than in men. >> reporter: hardeman recovered and went back to her gourmet business. but last june she had a second stroke. >> i had to stop being a ceo of my ice cream business and start being a ceo of my health. >> reporter: this time they found the cause. a small hole in

dr. jon lapook and cbs contributor dr. tara narula. doctor, how do you edit the gene?earchers used a special technique called crispr to find and remove the gene inside a human fertilized egg. it's kind of like finding a needle in a haystack. it's very difficult to do. the gene that caused the heart defect was gone. >> tara, you're a cardiologist. how do you react to something like this in. >> it's pretty amazing. >> yeah. >> they were pretty successful in that p 2% of the embryos did not have this disorder and they also didn't have any new muations in the 72%, which is also accident news. this is a disease that affects one in 500. what happens is the heart muscle does not form properly. there's no treatment for it other than symptomatic time. over time people can get pains, et cetera. if you hear of athletes who die suddenly on the field during a game, it's many times from this disorder, so this is excellent news. >> i feel like whenever they see this, people have to get on board. there are ethical questions. >> there's no doubt there are technolorj cal hurdles and eth