Older adults tend to feel that the younger generation has it “easier” than they did. However, when it comes to weight, the tables may be turned. A recent study from York University’s Faculty of Health concluded that for Millennials to maintain the same weight as people in the generation before them, they would need to eat less and exercise more.

Researchers reached this conclusion by analyzing diets of 36,400 adults from 1971 to 2008, and the physical activity of 14,419 adults from 1988 to 2006. According to Ruth Brown, lead researcher of the study, “for a given amount of self-reported food intake, people will be about 10 percent heavier in 2008 than in 1971, and about five percent heavier for a given amount of physical activity level in 1988 than 2006.”

What does this mean? Although maintaining a healthy diet and getting enough physical activity are imperative to the overall health of a person, there are other determining factors that are possibly leading to weight gain and contributing to the obesity epidemic. What factors? According to Professor Jennifer Kuk in the School of Kinesiology and Health Science, these may include, “medication use, environmental pollutants, genetics, timing of food intake, stress, gut bacteria, and even nighttime light exposure.”

Further research has shown that genetics may play more of a role in our weight than originally thought; however, many external factors possibly contributing to weight gain can be linked to environment and circumstantial necessity. For example, prescription medications can have multiple side effects — including weight gain — that one can reasonably question if the adverse effects are outweighed by the benefits. And we recently wrote about how certain chemicals we are all exposed to in everyday life are linked to obesity.

“Ultimately, maintaining a healthy body weight is now more challenging than ever,” says Kuk. She may be right. But challenging doesn’t mean impossible. If we all have to work a little harder to strive for a healthier lifestyle then that’s simply the reality of the new world we live in.