Just say no to the fries...but pass the diet soda!

And yet another study confirms what we've been saying all along: drinking diet soda will not result in weight gain.

A new Harvard study published in the New England Journal of Medicine demonstrates that "all foods are not equal, and just eating in moderation is not enough.” The federally funded analysis of data collected over 20 years from more than 120,000 U.S. adults found significant differences in how various foods and drinks — as well as exercise, sleep patterns and other lifestyle choices — affect whether people gradually gain weight.

The report reveals that foods like French fries and potato chips will generate weight gain. Cheese and diet soda, on the other hand, do not have any adverse impact on weight.

The researchers determined this by looking at the interaction between diet, exercise, sleep, television watching habits and weight gain or loss.

Some of the biggest offenders, when it comes to weight gain, include french fries, potato chips and sugary beverages. On the flip side, yogurt, nuts, fruits, whole grains and veggies helped boost weight loss. And, while some critics have claimed that diet sodas cause weight gain, this study shows that just isn't the case. These results are the latest in a long line of research that back the safety of diet soda and light products.

So bust out a can of your favorite diet cola tomorrow in celebration!