NEW YORK (CBSNewYork) – Shedding pounds is hard enough, but now new research shows there could be something else standing in your way.

Melinda Farina said she was doing everything she could to lose weight, but the scale wouldn’t budge.

“I’m eating perfectly, I’m working out, but I’m not losing this weight,” she said.

She was so worried she saw doctors and had bloodwork done.

“I completely thought it was hormonal. I went to get blood tests, went to endocrinologists,” Farina said.

Then, her nutritionist asked how much sleep she was getting.

“I was going to bed at like 2 a.m. and waking up at 6 a.m. for meetings. I was kind of like in zombie mode,” she said.

It turns out, your body needs rest to shed pounds. A new study by the American Journal of Clinical Nutrition shows sleep deprivation impacts the production of the two hormones that control hunger—leptin and ghrelin.

“When you’re sleep deprived for pretty much any reason, both of those hormones change in a direction that make your appetite go up so you really get hungrier,” Dr. Steve Feinsilver said.

Another study showed people who are sleep deprived will eat an extra 300 calories a day.

“If you eat another 300 calories a day, long-term you gain weight and it wouldn’t take that long to substantially gain weight,” Feinsilver said.

Nutritionist Robin Kaiden said it’s easy to see how bad sleep can derail a dieter’s best intentions.

“When you’re sleep deprived, you tend to make bad decisions. You don’t think clearly so you kind of grab what’s easy, what’s close. You’re too tired to think of something healthy, you’re too tired to cook,” Kaiden said.

Once Farina started getting a regular eight hours, she says the pounds melted away.

“Immediately in that first week my clothes started loosening up and the inches started coming off,” she said.

She said she sees benefits from getting more sleep beyond the decreasing number on the scale.

“My whole quality of life has changed. I feel so much better, I’m a lot happier,” Farina said.

Sleep needs vary, but experts say most people need between seven and nine hours a night.