Nathan Pritikin's goal, he says, is to change the food habits of this country. And now he is tackling the task in the supermarkets, with a line of soups, salad dressings, tomato sauces and rice mixes that are cholesterol-free, sugar-free (though in some case sweetened with fruit juice concentrates), reduced in sodium and contain less than 1 g. fat per serving.

Leaving all those things out costs money, of course, so these items cost more -- about 20 cents per unit, he said -- than standard fare. At Safeway that translated into dressings at $1.29 for 8 ounces, sauces $1.49 a pound, rice mixes at $1.29 for four servings and soups at least $1.19 a can, which at approximately 14 ounces is two servings, since the soups are not concentrated. At a luncheon to introduce the foods, the tomato soup was a hit, but it had been dressed up with yogurt and chopped raw vegetables. Salad dressings were quite sweet, with a gummy thickness rather than oily thickness; while no less palatable than many diet dressings, they are not a culinary advance. Brown rice pilaf had been vastly overcooked at the luncheon, and was dryly unpleasant, but then any convenience food that requires an hour of cooking hardly seems crucial to our food supply. And the Mexican sauce was all right -- mildly Mexican and notably saltless (with 35 mg. sodium per serving).

Particularly useful could be the low-sodium, low-fat chicken broth, though at 99 cents for 14 1/2 ounces it is expensive. Next to come are Pritikin frozen foods. So far we find these products a worthwhile attempt, particularly for people on low-sodium or low-fat diets, but not yet an answer or what a Pritikin spokesman billed as "a revolutionary breakthrough in convenience foods."