WORKERS who report instability in their income are more likely to also suffer insomnia, headaches and stomach issues, according to new research.

The findings, from a study by the Emlyon Business School, show a lack of financial security for an employee can have a negative impact on their physical health.

Gordon Sayre, professor of organisational behaviour at Emlyon, investigated the impact that pay volatility has on the health of gig workers’ and those who rely on tips.

Prof Sayre conducted three separate studies, surveying 375 gig workers across three weeks, 85 tipped workers each day for two weeks, and 252 higher-paid workers in sales, finance, and marketing across two months.

The findings revealed that workers who had more volatile pay reported experiencing more health symptoms such as headaches, backaches and stomach problems.

“Dealing with an unstable income means never knowing how much money you’ll make in a given week or month and that insecurity makes it difficult to cope with ordinary expenses,” Prof Sayre said.

The research also revealed that workers who rely on tips, such as restaurant servers, hairdressers and bar staff, didn’t feel physically better on days where they earned more money.

One thing that gig and tipped workers have in common is that they often have a lower-than-average income, raising the question of whether the harmful effects were simply due to low pay, instead of unstable income per se.

However, the results of a third study on workers in sales, finance, and marketing, where commissions and bonuses are common, revealed while the effects are not as strong, they still experienced health issues.

Prof Sayre said the research should encourage companies to consider whether the perceived benefits of performance-based pay policies that generate instability outweigh the costs to workers’ health.

Instead, he said companies should look to strike a balance by reducing workers’ reliance on volatile forms of pay, instead offering more substantial base pay.

The paper was published in the Journal of Applied Psychology.