During 1987 and '88, as it does every 10 years, the U.S. Department of Agriculture will dispatch an army of interviewers to thousands of households across the country to find out what Americans are eating.

The amount of information generated by this survey, and by similar nutrition surveys conducted by the federal government, is "mind boggling," says Alvin Riley, of the market planning department of Campbell's Soup Co.

"It's a gold mine," adds Susan Krebs-Smith, a Pennsylvania State University doctoral candidate in nutrition who is plowing through statistics from the USDA's last Nationwide Food Consumption Survey, in 1977-78, for a dissertation.

However, a coalition of nutrition professionals and public health officials believes the federal government should be doing a better job of surveying the dietary and nutritional status of the American public. It is supporting a bill that would make "nutrition monitoring," as the survey process is called, a more visible, higher priority and better coordinated effort in the federal government.

If you are wondering why Big Brother wants or needs to know what's on your grocery list, consider the uses that the government has for the survey data:

*The nutritional status of the population can be determined. If certain nutrient deficiencies are detected, they can be corrected through educational efforts, and if necessary, through food fortification. Recent survey data have shown that many women are not getting enough calcium, leading to recommendations that women boost consumption of low-fat dairy products.

*The quality of the food supply can be examined. For example, several years ago, the Food and Drug Administration, through analysis of foods in grocery stores and reported eating patterns in its Total Diet Survey, found sharp increases in iodine levels, several times above the recommended dietary allowances, in the American diet. After some investigation, the agency found several possible sources, including sanitizing agents used by the dairy industry, a dairy feed additive, and a dough conditioner used in bread products. Subsequent changes in industry practices have led to declining iodine levels in the American diet.

*The data can help to pinpoint nutrition research priorities and to further explore the relationship between diet and disease. Researchers have used the survey data to investigate the relationship between hypertension and sodium and potassium intake.

*The FDA and the Environmental Protection Agency rely on the data to determine safe levels of food additives and pesticides. The survey conducted by the Department of Health and Human Services -- the National Health and Nutrition Examination Survey (HANES) -- checks for pesticide levels in blood. A new system in place at the EPA will use the USDA's Nationwide Food Consumption Survey (NFCS) to break down pesticide exposure by age/sex groups to discover, for example, whether pregnant women or young children might be more at risk to specific pesticide residues than other groups in the population because they eat more of certain foods.

*The USDA analyzes the data to develop recommended "food plans," which consist of meals and menus for a week that provide adequate levels of nutrients. USDA nutritionists create plans that, as much as possible, follow current eating patterns. One of these plans, the "thrifty food plan," is used as the basis for allocating food-stamp dollars.

*Researchers have produced scores of scientific papers from analysis of the data, investigating such questions as whether snacking patterns make a difference in the overall nutritional adequacy of the diet (they do not), and whether lower-income households get more nutrients per food dollar than higher-income households (they do).

*The food industry has used the data to develop marketing strategies. Alvin Riley of Campbell's Soup says the company's intensive analysis of the surveys showed that people who consumed soups tended to be part of an identifiable group with an eating pattern that included more dairy products and less sugary foods. With this data in hand, Campbell's launched its "Soup is Good Food" campaign, which Riley credits with turning around declining per-capita soup sales.

Despite the enormous usefulness of the data, many say nutrition monitoring in the federal government needs to be more timely. Lynne Parker, a nutritionist with the Food Research and Action Center, a group concerned with the nutritional status of low-income groups, says that because government surveys of nutritional intake are not continuous, policymakers are not able to see whether cuts in food assistance are compromising the health of poor people. Nutrition surveillance involving hunger has in the past been crisis oriented and piecemeal, says Parker. When concern about hunger in America dies down, "the attention paid to it by Congress and the nutrition community dies down as well," she says.

Critics complain that the data generated by the surveys are outdated even before they are available. Many researchers are now working with 8-year-old data from the USDA's 1977-78 Nationwide Food Consumption Survey. Such obsolete information cannot pick up new trends or changes in the American diet. The problem is acknowledged by Robert L. Rizek, director of the nutrition monitoring branch in the USDA's Human Nutrition Information Service. "You need data every year to signal changes taking place," he says. In effort to respond to this need, the USDA this year has begun a two-year Continuing Survey of Food Intakes that will survey women between the ages of 19 through 50, as well as the children of these women who are 1 through 5 years old.

Other criticisms of the present system: there is not enough attention paid to assessing high-risk groups or to people in targeted geographical areas; the methods used to assess nutritional status are costly and imprecise; state and local governments need assistance so they can conduct local nutrition monitoring; and there is no outside involvement by academic experts or other nutrition professionals on how to improve the process.

But the major problem, says Parker of FRAC, is that "there's no sense that it is a high priority by OMB Office of Management and Budget or even by the agencies overall." Initiation of HHS' third HANES survey, for example, had to be delayed a year because of budget cuts, despite plans by HHS and the USDA to begin their surveys in the same year.

Congress has put pressure on the agencies in the past to better coordinate their efforts, but it took the USDA and HHS four years just to come out with a joint plan for implementing survey activities. One of the aims of the plan, which agency officials say has already been accomplished, is to make the data from the largest surveys, the USDA's Nationwide Food Consumption Survey and HHS' HANES survey, comparable by using the same food codes and survey assumptions.

Last year, a bill authorizing a 10-year program to gather continuous data on the dietary status of Americans fell 18 votes short of the two-thirds House majority it needed for passage. The administration lobbied against passage, complaining that the agencies were already working toward a national nutrition monitoring system and that the directorate and council proposed in the bill for overseeing the monitoring activities were cumbersome and inefficient.

A similar bill for a 10-year continuous nutrition monitoring program, introduced last month by 31 congressmen, would, like last year's bill, sponsor research on better survey techniques and assist state and local agencies to develop monitoring capabilities. It would also put all government monitoring activities under HHS jurisdiction and establish a new position in the department -- an administrator of nutrition monitoring and related research.

At a hearing last week before two House subcommittees, administration officials again opposed the bill, charging that it would impede rather than encourage progress in nutrition monitoring and would "confuse" the roles of the federal agencies.