Which profession drinks the most coffee?

Wednesday is National Coffee Day and in honor of the big day, Career Builder and Dunkin' Donuts wanted to know which professions demand the most coffee.

The study was conducted between Aug. 17 and Sept. 2 and included more than 3,600 workers nationwide.

The study found that nurses drink the most coffee followed closely by physicians.

The list of the 12 heaviest coffee drinkers is as follows:

1) Nurses
2) Physicians
3) Hotel workers
4) Designers/Architects
5) Financial/Insurance sales representatives
6) Food preparers
7) Engineers
8) Teachers
9) Marketing/Public Relations professionals
10) Scientists
11) Machine operators
12) Government workers

The study found that more than two in five Americans say they are less productive without coffee and 40 percent of workers between ages 18 and 24 admit they can't concentrate without coffee.

The study also found that 37 percent of American workers drink two or more cups of coffee during their workday.

To read the full results of the survey, click here .

Select Dunkin' Donuts coffee shops are giving out free coffee in honor of the day.

How much coffee do you drink? Let us know in the comments section below.