>>> as we mentioned earlier there is new research out tonight. it's shedding light on how a diet of red meat leads to heart disease . it is a study of 2600 people that pinpointed a compound that could be the culprit here apart from the saturated fat doctors have long worried about and warned us about. the story from our chief medical editor, dr. nancy snyderman .

>> reporter: 68-year-old wink baldwin has always been conscientious about food. eating meat only a few times a week.

>> the doctor says, you know, one of these days we have to think about lowering your cholesterol. it's borderline high.

>> reporter: after his brother had three mini strokes he became seriously concerned about the amount of red meat he was consuming. according to a new study his concern may beer warranted. in a report from the cleveland clinic published in nature medicine researchers believe they have found a new link between the consumption of red meat and heart disease . that's something called carnitine.

>> a diet with chronic exposure over time changes your metabolism and makes you more likely to generate or to have a metabolism that contributes to heart disease .

>> reporter: most scientists believe red meat increases the risk for heart disease . scientists long suspected that cholesterol and saturated fat are not the only contributors. researchers found carnitine become as powerful chemical in the gut. that chemical, tmao, is responsible for increasing the risk of heart disease .

>> we don't need to eat carnitine. our bodies make it naturally from protein.

>> carnitine is found in energy drinks and body building supplements. now scientists say they need to study the other products especially in young people . the american meat institute , the industry's largest trade organization says attempts to link cardiovascular disease to a single compound oversimplifies this complex disease. for wink baldwin, he's not taking any chances. he's now a vegan.

>> i feel great. since i went on the vegan diet i have lost 15 pounds.

>> reporter: thinner, healthier and more thoughtful about his heart and the food he eats. dr. nancy snyderman , nbc news, new york.