New research suggests that 25 year olds are more likely to struggle with their weight than their parents had to at that age.

Researchers from York University found that when eating the same amount of food, millennials "will gain more weight than their forebears 35 years ago," UPI reported.

"Our study results suggest that if you are 25, you'd have to eat even less and exercise more than those older, to prevent gaining weight," researcher Jennifer Kuk said in a statement. "However, it also indicates there may be other specific changes contributing to the rise in obesity beyond just diet and exercise."

For the study, researchers collected and analyzed dietary data from nearly 36,400 American adults. The available physical activity frequency data, of 14,419 adults in the 1988 to 2006 period was also used.

They found that when eating the same amount of food, people will be about 10 percent heavier in 2008 than in 1971, and about 5 percent heavier for a given amount of physical activity level in 1988 than 2006, Yahoo News reported.

"These secular changes may in part explain why we have seen the dramatic rise in obesity," Ruth Brown, lead researcher of the study, said in a statement.

The researchers point out that although several studies have shown that eating less and exercising more results in weight loss, in the long term, they are proven to be ineffective.

"This is because weight management is actually much more complex than just 'energy in' versus 'energy out'," Kuk said. "That's similar to saying your investment account balance is simply your deposits subtracting your withdrawals and not accounting for all the other things that affect your balance like stock market fluctuations, bank fees or currency exchange rates."

Kuk said that a person's body weight is impacted by their lifestyle and environment, such as medication use, environmental pollutants, genetics, timing of food intake and stress.

The findings are detailed in the journal Obesity Research & Clinical Practice.