With Thanksgiving right around the corner, 'tis the season for gratitude. And science says if you want to get the biggest happiness boost, you should not just give thanks but actually say thanks. Recent research finds that actively going out and expressing thanks to those who have positively impacted your life increases well-being significantly more than simply counting your blessings.

There's only one problem with this kind-hearted, research-backed advice: Most of us are lousy at saying thank you, especially at work. 

That's according to psychotherapist Sarah Greenberg. In a fascinating and seasonal Quartz article, the therapist and leadership coach insists that a great many of us make the same big mistake when we express gratitude--we "'just' all over it."

Stop "justing all over" other people's contributions.

What does it mean to "just all over" someone's contribution? As the phrase implies, it means minimizing the value of their work or help by peppering your thank you with the word "just" or its equivalents. It's particularly common in the office, Greenberg explains, offering the example of a boss dumping a load of work on an already busy employee right before a holiday break.

As this hypothetical manager drops off a mountain of work, he might say something like: "You know, I've been slaving away to prepare for Tuesday's deposition. Can you just review these docs? Shouldn't be a big deal. No need to go overboard. It's 200 pages, and at your fast pace, if you start now, you can still be out by 5 p.m. I know it's important for you to get to your family."

On the surface this boss is saying all the right things--he's showing interest in the employee's personal priorities ("I know it's important to you to get to your family") and praising her quick work. But all this is probably for naught, Greenberg writes, because he's also "acting as though a fairly large ask were minimal." The employee will most likely end up feeling resentful rather than appreciated.

Don't let your guilt undermine your gratitude.

Why do so many of us couch our thanks in these little expressions that minimize the other person's effort? Mostly because we feel guilty, Greenberg explains.

The boss in the example above, she writes, "may feel terrible for keeping a team member late right before a holiday. He sees himself as a compassionate manager who does all he can to support work-life balance. So he minimizes the expected effort in other to avoid the discomfort of acknowledging that he is acting against his own values. You don't want to feel you are putting someone out, so you minimize the task."

Sometimes the problem can even be simple ignorance--the thanker genuinely doesn't understand exactly how much she has asked of the thank-ee. But whatever the cause, the effect is the same. If you subtly minimize the other person's effort, they're going to feel resentful rather than recognized, and your thank you isn't going to do any good.

How do you stop "justing all over" those you want to thank? Simply being aware of the problem is a good first step, but reminding yourself that you owe it to the people in your life to be clear-eyed about their contributions, and that saying a proper thank you really does make people immensely happy (here's the science that proves this), can definitely help too.

So this week, when you're making a special effort to express more gratitude both at home and at work, make sure you're not letting one little four-letter word completely undermine your attempts to say thanks.