Way too much of a good thing.

FOR anyone in the early stages of a diet, Buca di Beppo is probably not the wisest choice.

Heaping plates of tortellini with cream sauce, chicken cacciatore, spaghetti and meatballs, and rigatoni with chicken and eggplant are among the traditional Italian favorites rushed out of the kitchen each night at the Santa Monica location.

The portions are so huge that, as longtime waiter Joaquin Garcia observed, newcomers almost find it scary.

"A lot of people are surprised (by the portions)," said Garcia, taking a break from a recent evening of serving. "The foreigners come in here and think it's nuts."

They're not the only ones.

Any number of restaurants around town, whether it's Buca, Cheesecake Factory or Jerry's Famous Deli, make oversized portions a calling card. But all restaurant portions are on the rise - so much so that the practice is coming under increased scrutiny as contributing to the nation's growing obesity problem.

Activists who in recent years trained their sights on McDonald's and other fast-food establishments for super-sizing, are now calling on sit-down restaurants to cut down on fats, reduce portion sizes or at least label the nutritional content of their meals.

"People think of fast food as being unhealthful, but often times the choices at sit-down restaurants have even more calories, salt and fat because the portions are so enormous," said Dr. Margo Wootan, director of nutrition policy at the Center for Science in the Public Interest.

Predictably, the industry has resisted, resting on the principal of personal responsibility, and opposing various labeling bills -- including one that was defeated this month in California.

Besides, few restaurateurs would have the stomach to take away what patrons have come to expect -- namely, gargantuan portions.

"Restaurants make food that customers like, and customers like food that tastes good -- and lots of it," said Bret Thorn, associate food editor of the Nation's Restaurant News, an industry trade magazine. "When restaurants offer lower fat food and smaller portions, people are not interested."

Growing portions, waistlines

Large portions are nothing new to the restaurant industry.

For decades, Jewish delis have made ridiculously overstuffed pastrami and other sandwiches their hallmark. Steak houses, with their 16-ounce New York strip steaks and baked potatoes lathered in butter and sour cream, are another example.

"Back in the 1960s, there was a big explosion of the beef and brew and Scotch and steak places," said veteran restaurant critic Merrill Shindler. "Steak houses have always been known for big portions."

But even the food industry acknowledges that the average portion size at restaurants -- including those not particularly known for it -- has been increasing as the relative cost of food goes down.

And they are not squeezing their profits in the process either. Depending on the type of restaurant, food costs only account for 20 to 40 percent of the bill, with rent, salaries and other overhead making up the majority.

"It's been a decade or so probably where portions have grown," said John Dunlap, chief executive of the California Restaurant Association. "The consumer feels he is not only getting a high quality meal but a generous serving."

Take Denny's Meat Lover's Skillet breakfast plate (ham, bacon and sausage over fried potatoes with cheddar cheese and two eggs). It has 1,150 calories and 26 grams of saturated fat -- more than a day's worth. "Making bigger portions isn't that expensive. It's easy to do, and customers think they are getting a better value," said Thorn.

But with an estimated 300,000 Americans dying each year from obesity related diseases such as heart failure and diabetes -- on track to pass the 400,000 annual deaths from smoking -- the question is whether big portions are turning out to be too much of a good thing.

A study by Penn State University released m May concluded that when diners are confronted with large portions they simply tend to eat more. They also perceive the portions as appropriate, even if 50 percent larger than normal.

All those concerns may be getting lost on the average diner.

Consider Artak Jaytyan, who was having dinner at the Santa Monica Buca last week. "That's the whole point of it," said Jaytyan, who had ordered pasta and a lemon chicken dish with a friend.

Indeed, restaurant owners that serve large portions insist that diners love the value, don't overeat and often take home doggy bags.

"I am very comfortable (with our portion size) and don't feel we need to apologize," said Randall Lopez, vice president of marketing for Buca Inc. "We are about the quality of the food and the experience."

Over at C&O Trattoria, a family style restaurant in Marina del Rey, owner Robert Singer concedes that the concept for his Italian eatery is "huge portions at ridiculously low prices."

It's been a hit, packing diners in for 11 years, and grossing $5 million annually. "People don't want to go in and be ripped off with snotty service and pay a huge amount of money and get a little dollop here and a little dollop here," he said.

But in a nod to the growing controversy over portion size and nutritional value, even Singer has made some concessions. The restaurant now offers more fresh seafood and non-cream based soups.

Some consumer groups want restaurants to go much further by having the nutritional content of meals listed, preferably on menus. While such information is commonly available at fast food chains, which faced potential legal action from states in the 1980s over the issue, only a few sit-down restaurants provide it.

Wootan said such labeling, especially on menus, could encourage restaurants to reduce portion size -- even though that has not been the case with fast food restaurants.

Bills have been introduced in eight states to require such nutritional labeling, but if California's experience is any indicator it won't be easy.

A labeling bill by Sen. Deborah Ortiz, D-Sacramento, went down to defeat earlier this month in the Assembly Health Committee, even though it allowed the information to be provided in pamphlets off the menu.

Ortiz said once the bill got off the Senate floor, there was heavy lobbying by the industry. I can only conclude that maybe they don't want the consumer to fully understand what they are consuming," she said.

Among the opponents was the Center for Consumer Freedom, an industry-backed group that has battled industry critics.

Mike Burita, the group's spokesman, says labeling could be the first of other efforts to infringe upon consumers' right to eat whatever they want, "It's one way down the slippery slope of more taxes, marketing restrictions and outright bans on food," he said.

So far, he may have the consumers behind him.

Tom Nitti, a Santa Monica attorney, eats at the local Buca regularly. He says he likes the fact it won't leave him hungry like some other Sanata Monica eateries. And while he checks labels on supermarket foods he buys, he has no interest in knowing the content of the oversized portions over at Buca's.

"I am indulging myself," he said. "That's he last thing I care about when I go out."

Big Portions, Fatty Foods

How some popular restaurant items add up.

                                               Saturated
Dish                               Calories  Fat (grams)

Slice carrot cake (Cheesecake         1,560           23
 Factory)
Half Chicago Classic pizza            1,500           30
 (Pizzeria Uno)
Meat Lover's Skillet (Denny's)        1,150           26
Stuffed potato skins with sour        1,260           48
 cream (typical)
Nachos with beef, cheese and sour     1,260           28
 cream (typical)
Fettuccine Alfredo (typical)          1,500           48
Prime rib (typical)                   1,280           73
Cheese fries with ranch dressing      3,010           91
 (typical)
Fudge brownie sundae (typical)        1,130           30

Average daily intake requirement      2,350           26

Sources: Centre for Sciene in the Public Interest; Food and Drug
Administration.