lustig: sure, all the time. but it's the truth. >> gupta: dr. lustig is a pediatric endocrinologist at the university of california, san francisco, and a pioneer in what is becoming a war against sugar. >> lustig: deep breaths. >> gupta: motivated by his own patients-- too many sick and obese children-- dr. lustig has concluded that sugar, more than any other substance, is to blame. what are all these various diseases that you say are linked to sugar? >> lustig: obesity, type ii diabetes, hypertension, and heart disease itself. >> gupta: lustig says the american lifestyle is killing us. and most of it, you say, is preventable? >> lustig: 75% of it is preventable. >> gupta: while dr. lustig has published a dozen scientific articles on the evils of sugar, it was his lecture on youtube, called "sugar: the bitter truth," that brought his message to the masses. >> lustig: i'm standing here today to recruit you in the war against bad food. >> gupta: by "bad food," dr. lustig means the obvious things such as table sugar, honey, syrup, sugary drinks, an

dr. robert lustig agrees. we need a balanced diet, but his idea of balance is a drastic reduction of sugar consumption. to that end he co-authored an american heart association report recommending men should consume no more than 150 calories of added sugars a day, and women just 100 calories. that's less than the amount in just one can of soda. >> ultimately this is a public health crisis. it's a public health crisis, and you have to do big thing and you have to do them across the board. tobacco and alcohol are perfect examples. we have made a conscious choice that we're not going to get rid of them, but we are going to limit their consumption. i think sugar belongs ms exact same waste basket. >> now, after that story first ran, we did hear back from the sugar association, and they say it boils down to this. that you can only fight obesity with the combination of changes to your diet and more exercise, and, of course, i think everyone agrees with that. they sent us a letter which says we should try to focus on

dr. lustig's controversial claims started to get worldwide attention with this lecture posted on youtubeled sugar, bitter truth. he said the big problem is how we consume it. it used to be most of our fructose came from real fruit and the surge of sugar was buffered by lots of fiber, not so with processed foods and americans now consume about 130 pounds of added sugars per person per year and you have this up and down spike in sugar in the bloodstream. >>> today is world autism awareness day. just last week the cdc released new statistics that estimate one in 88 children have autism in the united states. while scientists look for the reasons why, experts say the best thing parents can do is to educate themselves about the earliest warning signs. >> here goes green. good job. >> 5-year-old david koran was diagnosed with autism when he was 2. >> his first year i just noticed he was very unresponsive to me. he didn't have any language whatsoever, didn't want to imitate. that's when i knew that i had to get early intervention. >> his mom got him help right away. >> since he's nonverbal we're

dr. lustig has concluded that sugar, more than any other substance, is to blame. these various diseases you say are linked to shuger? >> obesity, type 2 diabetes, hypertension and heart disease itself. >> reporter: lustig says the american lifestyle is killing us. >> and most of it you say is preventable? >> 75% of it is preventable. >> a registered dietitian is with us now, cynthia sass. welcome. >> thank you. >> do we need to examine everything that has sugar in. >> we need to change our habits. the amount of sugar we're consuming is unprecedented. the american takes in 22 teaspoons, about 17 four-pound bags of sugar per person per year. >> why is it toxic? what does it do? >> think about a glass of water and imagine that's your blood. now think about pouring sugar into that water. the more sugar that's there, the thicker and more syrupy that water gets. when that's happening in your body n your blood, your heart has to work harder to pump that thicker fluid through your system. it puts stress on the heart. it puts stress on the arteries. increases blood pressure

dr. robert lustig, thank you very much.ind out ways to cut sugar from your diet. >>> and now, let's get the weather and sam. >> hi, katie. we're standing out here at the patch. by the way, i want to introduce you to a new anchor. ladies and gentlemen, hope bradfo bradford. >> good morning, sam. >> what's your first duty as an anchorwoman? >> here's sam with the weather. >> let's get to the boards. one or two things we want to talk about. we'll show you the twitter pictures. amazing pictures. we're getting hundreds of them in from this storm situation in texas. cars on top of each other. giant hailstones. all that hail damage on windows. and the homes destroyed in that direction. thankfully again, the period to that sentence is no one was killed in those storms yesterday. got an active day in the seattle/portland area today. you'll get a chance to see thunderstorms today. that cold air aloft kicking up a little. i wouldn't be surprised to see a rumble of thunder in that area. in the southwest, it's gorgeous. the storms are i