-By Dr. Carl Steidtmann, Chief Retail Analyst, Deloitte Research

Many years ago when I first went off to college, I learned to cook. Part of the reason was that I liked to eat and, being a poor college student, it was easier to eat well by eating at home. But the other reason was that I found that the old adage of the way to a man's heart being through his stomach worked the other way as well.

Since the early-1990s, the idea of eating at home has slowly lost out to cheaper, faster and more convenient restaurant food. The share of food eaten away from home has risen over that period from a little more than a third to a little less than half. A whole generation of Americans has shifted their eating habits from making dinner to making reservations. Even during the recession of 2001, sales of food stores fell while restaurant sales continued to climb.

After nearly two decades of eating out more often, Americans appear to be losing their appetite for the restaurant. For the first time in more than 15 years, sales growth at food stores is substantially above sales growth for restaurants. While the romantic in me would like to believe that this shift is being done for love, my economist side tells me that it's strictly for money.

The shift from restaurants to food at home reflects a seismic shift that is taking place in consumer finances. It is a shift that is likely to have a profound impact on a wide variety of different businesses, but particularly on food.

More than at any time in the past 15 years, the consumer is increasingly cash-flow-constrained. The cash flow boom during the middle of this decade was driven by moderate employment growth, broad-based tax reduction and very aggressive growth in mortgage equity extraction. At the peak of the housing boom, consumers managed to boost their household cash flow by roughly 9 percent by turning their home into an ATM.

With the collapse in housing prices and the tightening of lending standards, home equity is no longer a source of cash. At the same time, the modest employment gains of the past five years have been turned into modest employment losses. In the first five months of this year, employers have shed 325,000 jobs.

While consumers will get a small cash flow bump through the summer months from the tax rebates, by fall, this source of liquidity will have been spent. Rising gasoline and other fuel costs are further draining the consumer's limited supply of liquidity. Rising taxes next year will keep a lid on the growth in consumer cash flow.

Cash-strapped consumers can be expected to respond in a number of ways. They have already started to limit discretionary purchases. This has had a particularly negative impact on small luxury items like specialty coffee and large durable goods purchases like cars and consumer electronics. Budget constraints are also keeping more consumers out of restaurants and bringing them into food stores.

For many of the newly budget-conscious food consumers, cooking skills may be limited. Prepared foods are likely to do well with this customer who is still time-pressed in addition to being budget-constrained. Price becomes a bigger issue, and for food retailers, this is going to be a major challenge going forward. Despite the pickup in market share relative to restaurants, food stores have been posting significant increases in prices. Food inflation at grocery stores has been running at close to 6 percent versus 4 percent for restaurants. The growing price sensitivity of the consumer will work to the advantage of the more price-driven deep-discount food retailers.

What has been remarkable about the food business in general is that despite the widespread weakness that prevails throughout much of retailing, both food stores and restaurants continue to post better-than-expected results. With overall retail sales up just 3.6 percent in the first five months of the year, the 5.3 percent gain for restaurants and the 7.0 percent gain for food stores shows the food industry to be taking a greater share of the consumer's wallet in what are difficult times. Despite the higher cost, food remains one of the consumer's first loves.

To comment on this article or pose another topic for this columnist, contact Dr. Carl Steidtmann at csteidtmann@deloitte.com.