Pieters did a study on the bidirectional relationship between materialism and social isolation that was published in the in December last year.

In another paper published the same month in the , University of Michigan scientists proposed that retail therapy "has been viewed too negatively".

"People often shop when feeling sad, but whether and why shopping reduces lingering sadness remains an open question," say researchers from the Ross School of Business.

To investigate, researchers carried out three experiments involving 548 participants. They found that "making shopping choices helps to restore a sense of personal control over one's environment, and thus helps to alleviate residual sadness".

Shopping is undoubtedly a favourite pastime in Hong Kong, judging by the perpetually crowded malls.

According to research published last month by the Hong Kong Trade Development Council, domestic demand was the key impetus to growth of the territory's economy, with private consumption growing by 4.4 per cent year on year in the first three quarters of 2013, amid stable income and employment conditions.

The value of retail sales, in nominal terms, increased 11.6 per cent year on year in the first 11 months of 2013, after growing by 9.8 per cent in 2012.

Perhaps it's no coincidence that Hongkongers have among the world's longest living men and women - regular retail therapy has been shown to prolong life. In a study that appeared in the in 2011 of nearly 1,850 elderly Taiwanese from a nationally representative sample, those who shopped daily were 27 per cent less likely to die.

Those who went shopping more than once a week - 39 per cent - tended to be male and at the younger end of the elderly (above 65 years) spectrum. They also tended to be smokers and drinkers, have better physical and mental health, take regular exercise and have a network of dinner companions.

The authors, from Taiwan's National Health Research Institutes, acknowledge that shopping could be a surrogate for good health to begin with. But they suggest that shopping itself may improve health by ensuring a good supply of food to maintain a healthy diet, for example.

Shopping does not always entail making a purchase; it can be done to seek companionship, or take exercise. Shopping is easier than more formal exercise that usually requires motivation, the researchers say.

Even if a purchase is made, it doesn't have to involve costly items. "Treating myself to nice meals or buying interesting produce at the supermarkets works for me, not so much for other products," says Wong Pei-yan, 31.

Different people have different ways of coping with stress. Some common methods include rumination, binge eating, getting drunk or indulging in physical activity.

Grace Ho, 32, a mother of two, prefers food as therapy. "I think food has more of a hold on me than shopping. Shopping does nothing for me, especially with crowds and sales."

Is shopping really a worse way to deal with sadness or stress? If you're a materialistic person to begin with, you're more likely to seek comfort from bad events in compulsive and impulsive consumption, and that could amplify traumatic events, says Aric Rindfleisch, a business professor at the University of Illinois at Urbana-Champaign.

"If you're a materialistic individual and life suddenly takes a wrong turn, you're going to have a tougher time recovering from that setback than someone who is less materialistic," says Rindfleisch, who co-wrote a paper published last month in the .

"At its core, materialism is a value-based response to insecurity in one's life," he says. "Our research more broadly suggests that it's also about existential insecurity. This idea that we're all aware of our mortality and focusing on that can be almost debilitating."

His research studied the experience of traumatic stress and maladaptive consumption through an Israeli field study and a US national survey.

When faced with a mortal threat from a terrorist attack, highly materialistic individuals in Israel reported higher levels of post-traumatic stress, compulsive consumption and impulsive buying than their less-materialistic peers.

The US-based portion of the study, which asked people about their level of death anxiety, suggests that these effects are likely due to materialistic individuals exhibiting lower levels of self-esteem, which lessens one's ability to cope with traumatic events.

But retail therapy is only a short-term fix. "Soon after purchasing something, there is a reduction of anxiety. But it doesn't last very long. It's fleeting," says Rindfleisch.

For Gareth Bridges, a business manager at an IT company, retail therapy is "short-term and low-intensity gratification".

"The therapeutic effect from accomplishing personal goals is stronger and more fulfilling than anything I've experienced from retail therapy," says Bridges, an avid runner and cyclist.

"For example, I can't imagine what I would need to purchase to get the same feeling as achieving a marathon personal best."

But the retail industry knows just how vulnerable consumers are and will often try to manipulate those emotionally driven purchases.

Retailers often use "smell marketing" to persuade you to part with your money, according to researchers at Tel Aviv University's Sackler Faculty of Medicine. In their 2008 study published in the journal , the researchers found that depressed women lose their sense of smell and may overcompensate by using more perfume.

Because of this link between the sense of smell and depression, researcher professor Yehuda Shoenfeld says retailers and banks use aromatherapy as a marketing tactic. "The retail industry has learned that if it splashes good smells around, it can convince clients to buy more and invest more money," says Shoenfeld. "It certainly has an effect on one's mood."

According to Professor Bernd Schmitt, executive director of Singapore's Institute on Asian Consumer Insight at Nanyang Technological University, retail therapy really works.

"While consumerism and marketing are often critiqued as distracting people from finding happiness, if done with a genuine interest in consumers as real human beings, they can enhance individual well-being, quality of life and life satisfaction," says Schmitt, author of the 2012 book .

"Shopping, buying and consuming can result in pleasurable moments, and sometimes meaningful and engaging experiences that create happiness."