The obesity spike is expected to double the number of people with diabetes in the next 25 years. At the same time, the number of people with Alzheimer's disease will nearly quadruple. But there are ways to circumvent your genes and it may be simpler than you think.
Shannon Seitz watched Alzheimer's destroy her 50-year-old mother.
"You know exactly what you are going to lose. You know, step-by-step, so that's very frightening," she said.
Shannon couldn't save her mom. Now she's focused on saving herself, but wonders if everything she's doing - training for a marathon, eating right, staying stress-free and playing brain games -- will make any difference.
"Actually, you can beat your genes," said Dr. Emile Mohler, University of Pennsylvania.
Whether it's Alzheimer's or heart disease, doctors say do you have some control. New research shows something called the Epigenome makes that possible. It's a complex network of chemical switches that control your genes, which means everything you come into contact with or put into your body has the power to turn genes on or off.
The American Institute of Cancer Research reports that even with a family history, 45 percent of colon cancers, 38 percent of breast cancer, 69 percent of esophageal cancers would never occur if Americans ate better, weighed less and exercised more.
"If you're sitting in front of your television watching this, get up afterward and exercise," said Dr. Lewis Lipsitz, director for the Institute for Aging Research Hewbrew Seniorlife.
Although Shannon is doing everything right, she still worries.
"Every time I forget someone's name, or if I change rooms and I forget where I was going, I'm terrified for an instant that I have Alzheimer's," said Shannon.
A woman taking action hoping her family's past doesn't become her own future.
Tricking DNA may be another way to extend life. Last year, researchers at the University of Washington found a way to tweak the genes of roundworms so they lived longer and healthier lives. The same approach could one day be used to protect humans from the damaging effects of stress.