A quick mocha and a bagel in the morning. A burrito on the go at lunch. A restaurant dinner with friends at night. Increasingly, Americans are eating their meals away from home as part of their daily routine.

Few even think about how many extra calories they pack away when they let someone else do the cooking. But Jennifer Morris does.

A nutritionist with a doctorate from the University of California, Davis, Morris knows a venti mocha adds up to nearly 400 calories unless you ask for nonfat milk. The cinnamon raisin bagel and cream cheese totals about 430 calories. Together, that's nearly half a day's worth of calories for most people before noon.

"It's a big beef of mine, these big portions," said Morris, who has worked on childhood-obesity projects, led workshops for parents, taught general-nutrition classes at community colleges and counseled clients at fitness centers. Recently, she became director of a Health Fitness Corp. program at a biotech company in San Jose, Calif.

Morris joined me on a tour of popular local restaurants to point out the minefields and suggest strategies to survive an ordinary day of eating out. "Go wherever you want to go," she advised, "as long as you watch what you eat, and you don't go every day."

Most adults require 2,000 to 2,500 calories a day, depending on age, gender and activity level. Keeping within that range and avoiding weight gain requires more discipline if you're getting the majority of your meals away from home, whether in a restaurant or at the takeout counter of a supermarket.

Still, Morris doesn't take an ascetic's view of eating. "It all comes down to you have to enjoy what you're eating," she said. "If you don't like it, you're not going to eat it, so it's a moot point."

Our first stop was Starbucks, the ubiquitous temple of caffeine. Even coffee has been supersized, Morris pointed out. That's not a problem, at least in terms of calories, if you drink it black, but more elaborate coffee drinks rack up the calories with whole milk or cream and flavored syrups. The eight-ounce "short" size has been dropped from the menu. Now, the 12-ounce "tall" is the smallest serving listed. The largest, venti, is 20 ounces.

Beware the venti caramel macchiato, she warned. Made with whole milk, the default formula, it totals 380 calories. A frappuccino of the same size can run up to 770 calories with whipped cream.

A beverage can be a dangerous dietary pitfall, she noted. "There's no substance to it, so people don't think of it as having calories," she said.

Morris chose a grande latte (16 ounces) made with nonfat milk at 160 calories. There's protein, which helps fill you up, and calcium in the milk, "so on some level this is an entire meal," she said with a smile.

BEWARE OF BAGELS

To go with it, there's usually a case of baked goods, or perhaps a bagel. Be aware that today's bagels average around 4.2 ounces and 350 calories — the equivalent of four pieces of bread, she said. Two tablespoons of whipped cream cheese raises the total to more than 400 calories.

Morris suggested going easy on the cream cheese and eating only half the bagel or choosing a mini-bagel if it's available. Make it whole-wheat to ensure you're getting fiber.

Fat, a calorie-dense nutrient, is an issue in most restaurant meals. Even if you're not concerned about cholesterol, it ratchets up the calories quickly. No matter which dietary regimen you choose, there's no getting around the fact that calories count.

"Technically, breakfast should be around 500 to 600 calories, lunch 600 to 700 calories and dinner 1,000 to 1,200 calories," she pointed out. Moderately active adult women require about 2,000 calories a day and men about 2,500, according to government guidelines. (For older people who are not active, the recommendation drops to 1,600 for women and 2,000 for men.)

For lunch, we stopped at Baja Fresh, a chain that touts its fresh, charbroiled ingredients and lard-free burritos, tacos, soups and salads. Morris was impressed by the menu offerings, particularly the Burrito Mexicano with meat, rice, black or pinto beans, cilantro, onions and salsa. It's not loaded with the cheese, guacamole and sour cream that make most burritos problematic.

She was surprised, however, to find that the chicken version weighed in at a pound — with 940 calories, 20 grams of fat, 52 grams of protein and 22 grams of fiber — when we looked at the nutritional information I had downloaded from the chain's Web site.

"Even though it's high in calories, that's a good amount of fiber," she said. "This meal has staying power. There's a ton of protein and a ton of fiber. The only downside I can see is there are no vegetables."

It would be a good lunch for a man who does physical work, she suggested. Women and computer jockeys would do better to eat half and save the rest for later.

MAKE GOOD CHOICES

Other acceptable choices she identified included the Baja Ensalada with fat-free salsa verde dressing; the Bare Burrito — the fillings served sans tortilla in a bowl; and the grilled veggie burrito, as long as you hold the sour cream, which contributes 26 calories and 3 grams of fat per tablespoon.

Cheese bumps the bean and cheese burrito with chicken up to 1,120 calories and the steak up to 1,210. The Ultimo, with rice plus cheese and sour cream, is 1,030 calories for chicken and 1,120 for steak.

"It's really important at a place like this, when possible, to get cheese and sour cream on the side," she said. "Look at the beautiful salsa bar they have. Add some flavor that way."

She found the Burrito Dos Manos appalling even before she learned that the nutrition chart lists the steak version as the equivalent of two servings of 885 calories each. "The fact that this Burrito Dos Manos says it's huge scares me," she said, looking up from the menu.

Dinner at Romano's Macaroni Grill in Milpitas, Calif., posed more challenges. Like most full-service restaurants, it's a place where calories add up rapidly. The most extravagant dish is the spaghetti and meatballs with meat sauce at 2,270 calories, but most entrees run at least 1,000 calories.

Even the steak and arugula salad with bacon and blue cheese, billed on the menu as a sensible choice, runs 990 calories with dressing, according to nutritional information on the restaurant's Web site.

"I find it interesting they call this sensible. It has the most amount of calories, the most amount of fat — it has twice the amount of saturated fat as anything else" on the salad menu, Morris said. "That's just crazy."

DANGERS OF DRESSING

Dressing just about doubled the calories of most of the salads on the menu, "which is more proof that you need to order dressing on the side and use just a little."

While we studied the menu, a hot loaf of bread (500 calories) arrived at the table with olive oil for dipping. Of the antipasti, Morris pointed out, "the best choice is the mushroom ravioli and the tomato bruschetta, and they're 800 calories." To be fair, they're also meant to be shared. But the calories do add up.

We ordered the bruschetta, a garden salad and a Caesar with low-fat dressing on the side, the spaghetti and meatballs so we can see how big it really is, and the "skinny chicken" (310 calories) to evaluate one of the lowest-calorie options on the menu.

The salads are generous. "You don't have to order an entree, their salads are so big," she noted. "A salad and an appetizer would be a good meal."

When the spaghetti came, Morris suggested I get a takeout container and put at least half of the food away for a future meal before I even started eating. Otherwise, she pointed out, I'd probably start talking and lose track of how much I was eating.

Her simply grilled chicken breast on a bed of steamed spinach with tomatoes and fat-free feta cheese was attractive but disappointing. "Taste-wise, it's nothing special," she said. "It says, 'I'm on a diet.' "

Dessert was out of the question for me by then. If I had eaten everything I had ordered and the bread, I would have been up to more than 3,000 calories. None of the desserts had fewer than 1,000 calories, and the dessert ravioli with vanilla ice cream and caramel sauce ran 1,720 calories.

"Dessert," Morrison said firmly, "should be shared."