A bloated belly is often related to diet, but sometimes more serious conditions could be a factor.
You OD on veggies

If your belly feels a littler bigger than usual, don’t freak.
“Unless it’s associated with weight loss, nausea, or vomiting, bloating is very common and usually not worrisome,” says Robert Burakoff, MD, clinical chief of gastroenterology, Brigham and Women’s Hospital.
It’s often nutritious foods that could be the culprit of a little extra air in your tummy.
Chowing down on beans, Brussels sprouts, cabbage, apricots, or carrots can lead to bloat, says Gina Sam, MD, director of the Gastrointestinal Motility Center at Mount Sinai Hospital Foods high in lactose, dairy’s main sugar, and foods high in fiber, which can lead to the release of bloating gases hydrogen and methane, can puff you up too, says Dr. Burakoff.
You eat a lot of ‘diet’ foods

You’ll find the sugar substitute sorbitol in diet soda as well as in certain sugar-free foods and drinks and certain foods marketed as “diabetic.”
Snack on this stuff enough, though, and you’ll notice your pants tighten up, says Dr. Sam.
Even the sweetener Splenda’s website states “sugar alcohols (such as mannitol, sorbitol, xylitol, lactitol, and maltitol) are sometimes a cause of bloating and diarrhea if too much is eaten.”
Your best bet is to cut back on the sweet stuff, fake or not—even real sugar can puff you up, says Dr. Sam.
Your beverage of choice is bubbly

Champagne, soda, and seltzer water might seem like three very different drinks, but the carbonation in a bubbly beverage has the same effect on your stomach.
Bubbles expand in your gut and could lead to a slightly bulging belly, says Dr. Sam. Stick to straight water if you’re feeling bloated.