Ms Clements said people should try to ease back into work.
"Try thinking about when your next break is so you're not contemplating an endless work period without any break," she said.
"For some it might be a good time to think, 'Well, if coming back to work feels so gloomy and awful, is this really the right place for me? Is this something I should be thinking about or talking to others about?' So that kind of reflection can be useful."
Ms Clements said it was important people looked after themselves - including getting enough sleep, eating well and exercising.
She said the blues was a fleeting feeling for most, but those who were still anxious or down after a few weeks should consider talking to their GP.
"It might not just be back to work blues - it might be depression or an anxiety state that needs some help."
Auckland University workplace psychology expert Helena Cooper Thomas said holidays were good for recovering but the effects were "relatively short-lived".
She said people returning to work should continue to make the most of the good weather and make time for activities they enjoy, such as exercise, hobbies, gardening or music.
"Don't get sucked back into a daily grind kind of existence - try to make sure that you're making space for those activities that really give you pleasure and that allow you to recover from work and give you balance.
"In everyday life, if you can try and make your experiences outside of work as positive as possible and find things that you enjoy and give you pleasure, it will make you better at work as well."
Dr Cooper Thomas said in order to feel engaged at work, people needed be mentally and physically available, feel safe in the work environment and consider their work meaningful.
She said some people might not want to return to work because of availability issues, such as anxieties about childcare, or safety issues, like an unpleasant workplace environment.
"So they have to consider these factors and they might need to change what they're doing. But otherwise, just try to focus on the good."
Dr Cooper Thomas said setting goals could be "very motivating" and people should think about what they wanted to achieve in the year ahead, such as getting a promotion or learning new skills.
"You may even want to look for a new job this year, but it's a good time to assess what you're trying to achieve over the next year.
"I think it can be very motivating to know your overall aims for the year ... Unless you've got a plan of where you're going to get to then you're just aimlessly wandering."
Trade Me spokesman Paul Ford said job search traffic on the site went quiet over the Christmas - New Year period, but it would start increasing again this week.
"As the 'first day back at work' for a chunk of Kiwis, we expect today will mark the beginning of a ramp-up in traffic as people get back from their breaks and contemplate a career move," he said.
Although the traffic would increase from today, job searches would really kick off from next Monday and the following week.
WHAT ARE THE SIGNS OF BACK TO WORK BLUES?
* Feeling disoriented and taking a 'go-slow' attitude
* Little interest in work or focussing on your next holiday
* Feeling irritable, in a bad mood or suffering headaches
WHAT CAN YOU DO TO REDUCE IT?
* Organise your work space and give your desk a personal touch
* Think about learning some new skills this year
* Arrange a job review to discuss ways to stay fulfilled and challenged
* Ensure you have at least 15 minutes a day of personal time
* Arrange after-work activities to look forward to on evenings or weekends
* Look after yourself - get more sleep, exercise, and eat better
WHERE TO GET HELP IF YOU'RE STILL DOWN
* Speak to your GP or someone you trust
* Call Lifeline on 0800 543 354
* Call Youthline on 0800 376 633
* Talk to the depression support line on 0800 111 757
(Source: Mental Health Foundation)
