SMORGASBORD THE FOOD FILE : Eat and Be Fit : A visitor to The Oaks at Ojai can feel both full and virtuous on 1,000 calories a day.

Ever wondered what the food’s like at one of those “health spas” you see advertised? I mean, we’re talking a bunch of overweight yuppies running around in sweat suits and munching on carrots and yogurt, right? Dinner would be a big deal, with three shrimp relaxing on a plate next to a couple of undercooked spears of asparagus.

Imagine, then, my surprise when I ended up feeling both full and virtuous after consuming fewer than 1,000 calories in three meals at a Spa Day at The Oaks at Ojai. Since I’m a sort of a 3,000-calories-a-day-guy--not counting the martinis--I had some trepidations. They didn’t lessen as I drove to the place early that morning. The first thing I saw was a group of women (most of the spa’s clientele is female) in sweats doing stretching exercises.

I quickly reminded myself that my reason for being there was to check out the food, and I didn’t really have to work up much of a sweat to do that.

But I nearly broke into a sweat when I walked into the Winner’s Circle--The Oaks’ casual, over-the-counter breakfast and snack area--and saw the “basic breakfast” plate: several slices of a less-than-distinguished grapefruit topped with a large strawberry and seated next to what turned out to be a moist, very sweet (too sweet for me at that time of the morning) banana-and-raisin bran muffin.

But then I spotted the other options. Like a hard-boiled egg, stewed prunes, yogurt and shredded wheat. Hold me back, I thought.

Both regular and decaffeinated coffees were available, along with a bunch of herb teas.

The Winner’s Circle is a light, airy room, uncomfortably situated right next to the weight workout area. But you can also take that hefty breakfast out to the pool area and eat your grapefruit under the orange trees.

While you wait for the next feeding, you can sandwich (pun intended) in workouts with titles such as “Body Dynamics” and “Aerobic Body Contours.”

I, of course, was waiting eagerly for the 10:45 a.m. “broth break.” I needn’t have. Since I hadn’t been making use of the workout facilities, I didn’t need the energy-giving vitamins apparently hiding in the warm, flavorless liquid of dehydrated vegetables--supposedly especially high in potassium.

By the time I’d strolled the streets of downtown Ojai--and my fellow guests had worked on their thighs, hamstrings and stomachs--it was time for lunch.

Lunch made up for much of what had gone before. It began with a fruit soup, cold and straight from the blender. Made of fresh strawberries, melon, pineapple and buttermilk, it had a tangy sweet-and-sour flavor that both tasted good and made me feel just a little virtuous.

The soup, and everything else on the menus, is developed by food consultant Eleanor Brown, who has written several books on food and nutrition. She also teaches yoga at The Oaks.

After the soup came a pasta primavera, which was a cold dish done with pasta, chunks of a low-salt Swiss cheese, sun-dried tomatoes, regular tomatoes, mushrooms and artichoke hearts. It was topped with a house Italian dressing and Parmesan cheese. On the side was a very tiny, very cold roll. Don’t even ask about butter.

Dessert was an excellent baked pippin apple with that nice tartness that pippins give and a honey-sweetened meringue.

You can get either a poultry or a high-fiber salad instead of the normal lunch menu, but I got up from the table quite satisfied with the food and with its quantity.

After lunch, while some of the group was in the pool doing something called aquatronics, we nonbelievers were soaking up the sun, waiting eagerly for the 3:45 p.m. “vegetable break.” Don’t get excited. Fresh vegetables, carrots, cherry tomatoes, zucchini and so on. But no dressing. This meal was for the purists.

Dinner was as satisfying as lunch, and actually tastier. It began with a green salad with a blue cheese dressing. The entree was a gently cooked piece of fresh orange roughy covered with an herbed yogurt sauce. The almost-sweet fish against the sourness of the sauce was a fine touch.

On the side was wild-rice pilaf and fresh, crispy, very plain green beans. They’d been billed as almondine, but I think they forgot the almonds. Dessert was a heavy, grainy carrot cake with a unique coating of smooth cottage cheese flavored with orange juice.

The tab? The program, including the food, for a day that begins as early as 6 a.m. and ends as late as 9 p.m., costs $80. “The reason we can be so affordable,” owner Sheila Cluff said, “is that we’re a single-menu restaurant--linked with an especially effective body and health program.”

Now if they could just find some way to come up with a healthy martini.

* THE PREMISE

Smorgasbord is a new intermittent column on a variety of food topics.