Lead researcher Dr. Dale Corbett, scientific director of the Heart and Stroke Foundation Center for Stroke Recovery, and colleagues gave sedentary rats unlimited access to both nutritional food pellets and a daily selection of common junk food items including cookies, sausage and cupcakes.
The animals were given access to both water and a 30 percent sucrose solution designed to imitate soft drinks. Like humans, the rats greatly preferred to consume the treats.
The rats were at an age roughly equivalent to age 16-22 in humans.
The study found the high-sugar, high-sodium diet induced most symptoms of metabolic syndrome -- a combination of high levels of cholesterol, blood sugar, blood pressure and obesity -- in rats after only two months.
"I think we'll soon start to see people in their 30s or 40s having strokes, having dementia, because of this junk food diet," Corbett said in a statement. "Young people will have major, major problems much earlier in life."
Corbett emphasized the importance of preventing metabolic syndrome with regular exercise and a balanced diet.
"We're not sure whether metabolic syndrome can be reversed," Corbett said. "If it can't, and we continue to live and eat like this, then we're each a ticking time bomb of health problems."
The findings were presented at the Canadian Stroke Congress in Calgary, Alberta.