They say breakfast is the most important meal of the day.

If you count fat and calories, it could end up being your only meal of the day.

We looked at calories, fat and carbs at breakfast hotspots.

Warning: high numbers ahead.

There's nothing like a big omelet and hash browns with crisp bacon and toast dripping with butter. It's guaranteed to fill you up... at least until lunch.

So will the Granny Omelet at Perkins Restaurant. With its stuffing and sides of hash browns, and a monster muffin on the side, it's got a monstrous calorie count: nearly 1,800 calories, and enough fat to cover you today, and tomorrow.

Denny's claim to fame is its Grand Slam Breakfast. The calories are out of the park at 1,150, and a whole day's worth of fat. That's before you add syrup to the pancakes!

How about a Colorado Omelet and pancakes at the IHOP? 1,200 calories. Almost makes the Rooty Tooty Fresh and Fruity look like a good choice-- at 865 calories.

Getting your breakfast to go will save you time... and a few calories... But it's not a big improvement.

A Burger King Omelet sandwich stacks up to 730 calories.

McDonald's big breakfast is 720.

And the new breakfast burrito from Hardee's-- 920 fat-filled calories.

It's definitely food for thought, says dietitian Laurie Meyer. "When people are eating that for breakfast it's really what they need for the whole day and I really don't think they keep that in mind when they're eating a breakfast like that."

Meyer says you can have a big breakfast, but cook it at home. Substitute whole wheat toast for white toast with butter. Use egg beaters or make an egg white omelet. Shred your hash browns yourself, and use nonstick spray to cook with. And watch those portions.

The same goes for breakfast drinks. One black coffee with sweetener equals 6 calories. A Starbucks venti-size white chocolate creme-- 600.