iStockphoto/Thinkstock(NEW YORK) -- A group of psychologists have added a twist to the so-called "lipstick effect" -- the idea that women will buy less-expensive luxury goods in hard economic times -- saying women spend more on beauty products to increase their attractiveness when there are fewer "high-quality men in a woman's mating pool."

But at least one economist questions whether the finding has less to do with human nature and more with over-generalizing gender stereotypes.

The researchers, which included professors from Texas Christian University, University of Minnesota, University of Texas at San Antonio and Arizona State University, presented five studies in the paper.  It's entitled "Boosting Beauty in an Economic Decline: Mating, Spending, and the Lipstick Effect" and was published last month in the Journal of Personality and Social Psychology.

Guided by evolutionary theories, the group hypothesized in the paper, "Because economic recessions are reasoned to prompt women to expend more effort on mate attraction, is it possible that they may spur women to spend more on products that make them more attractive?"

In one study, the researchers had 154 university students, including 82 women and 72 men, read fictitious news articles describing harsh economic conditions, including staggering unemployment with no end in sight.  The participants were then asked if the reading material caused them to think there were fewer people in their social circle with a good job, steady income, a lot of money, who are physically attractive, "have a sexy body" and a "nice-looking face."

As the researchers expected, the article "led people to perceive that there are fewer people in their local environment who have good jobs, a steady income and a lot of money."  However, the two articles did not alter people's perceptions of the numbers of people who are physically attractive, have a sexy body, or have a nice face.

The participants were then asked based on their gender about their desire to purchase six products.  Three products enhance physical appearance: form-fitting jeans for both genders, form-fitting black dress for women or form-fitting polo shirt for men, and lipstick for women and facial cream for men.  The other three products were a wireless mouse, stapler and headphones.

While the researchers found no main effect of product type on purchasing desires for the men, they found a "significant interaction between priming condition and product type" for women.

"As predicted, women in the recession condition reported a significantly greater desire to purchase products that could enhance appearance compared with women in the control condition," the paper stated.

Julie A. Nelson, chairwoman of the economics department at the University of Massachusetts, Boston, questioned the study's hypothesis.

"It claims to find that spending more on beauty-enhancing products during recessions is an aspect of "women's psychology," and strongly suggests that this is an evolved response to competition for mates in hard times," she told ABC News.  "The first part of this is a gross over-generalization, while the second is speculative."

Nelson said the "findings come from study of only a narrow sub-class of women," young university students within the U.S.

In another study, the researchers hoped to study "general feelings of uncertainty" and predicted that feelings related to a recession "would lead women to report being more concerned with their physical attractiveness."

The researchers asked 36 unmarried female university students to view a slideshow summarizing a news story about the dire state of U.S. unemployment.  Another 40 participants were shown a slideshow summarizing "stringent academic requirements imposed by college administrators" as a control for the experiment.  The women were then asked a series of questions.

The recession slideshow led women to report wanting members of the opposite sex to think that they are pretty, to report that it is important to look good, and to report caring more about how attractive they look.  But the two groups did not differ in the degree to which they made women feel that the future is out of their hands, that the world is an unpredictable place, or that they feel uncertain about what tomorrow may bring.

Nelson said it is "plausible" that the purchase of beauty products is an evolutionary outcome of competition for mates, "but an explanation being plausible is a far cry from it being scientifically demonstrated."

Copyright 2012 ABC News Radio