Eat like a caveman. That's the message behind the Paleo Diet, which is all the rage these days.

The basic premise is to consume foods that were available to our hunter-gatherer ancestors in the Paleolithic era, which ended about 12,000 years ago. That would include a lot of lean meat, vegetables, nuts and berries. Gluten, legumes and refined cooking oils are given the cold shoulder. Don't even think about doughnuts, pizza, potato chips, candy bars or any of the items that lead to obesity and heart attacks and that were not available in Paleo times.

Loren Cordain, author of "The Paleo Diet" and a professor in the Health and Exercise Science Department at Colorado State University, is among the leading experts on the diet. He says the ground rules are:

- All the lean meats, fish and seafood you can eat.

- All the fruits and vegetables you can eat.

- No cereals or grains.

- No legumes.

- No processed foods.

Why follow the diet? It was a combination of reasons that led the three founders of Progressive Paleo, a Colorado Springs-based company that prepares food for "primal eating," to start the business about a year ago.

"I was doing CrossFit and wanted to lose some weight," said Ramsey Lowe, one of the partners. "I wanted to eat clean so I could improve my performance."

Pete Moreno, another partner and the executive chef at MacKenzie's Chop House, got interested in the diet for weight loss.

"I was doing the Zone Diet," he said. "But I got interested in the Paleo Diet when Ramsey was getting good results from it. I lost more weight and was feeling better. Everyone at the gym we go to seems to be doing the diet."

As for the third partner, Skip Graham, "I haven't been following the diet as long as Ramsey, but I was wanting to eat better. I feel like I have a clearer mind, and I have more energy."

Starting a food business that prepares Paleo meals was Lowe's idea.

"It was taking me a long time to prepare the meals," she said. "Shopping for the best ingredients, then taking them home to prepare - I kept thinking, 'I'd pay someone to do this.'"

With Moreno's cooking background and a commercial kitchen where they could rent space to prepare the meals, the company was born.

The menu includes entr?s such as Adobo Chicken with "fried rice" (cauliflower), ginger, carrots, peas and green onions; and Chili Stuffed Sweet Potato, which is an oven-roasted sweet potato smothered in grass-fed Paleo chili.

The meals are freshly made and refrigerated. "They can be microwaved or heated in the oven," Moreno said.

Owners of Progressive Fitness CrossFit, Beth Hoppe and her son, Chris Hoppe, are big fans of Progressive Paleo.

"They sell a lot of dinners at our gym," Beth Hoppe said. "Many of our athletes follow a paleo diet. The pre-made dinners make it easy and convenient for people to do the diet."

Ashley Sara DeKam, owner of Craving4More, a nutrition and health consulting business, believes "the Paleo Diet is truly the key to optimal health." She follows the diet because she is eating real food - nothing processed or refined - for optimal health. She goes for grass-fed beef to get the benefit of omega 3 fatty acids.

"Additionally," she said, "a paleo lifestyle is not just about food but living smart, including exercising smart."

Patricia Kulbeth, a clinical dietitian at Memorial Health System Outpatient Nutrition Services, sees the benefits of a paleo diet that encourages eating fresh fruits and vegetables, cutting out processed foods, using lean meat and avoiding sodium and processed sugar.

"These agree with all healthy diet plans," she said. "However, cutting out dairy, legumes, beans and whole grains may lead to nutritional deficiencies, a lack of variety and choice in the diet. It can be a high-cost dietary pattern and increase the fat intake above recommended levels for heart-healthy eating as defined by the American Heart Association."

To be sure you are meeting your nutritional needs on a paleo diet, Kulbeth said "periodic blood tests may be necessary to determine if any nutritional deficiencies or excesses are found, and if any further supplements are required to make up for the lack of nutrients caused by adherence to this diet."