Answer:

dieting

Answer	Crossword Clue
DIETING	Eating carefully
DIETING	On the way down, perhaps
DIETING	Counting calories.

DIETING	Health measure.
DIETING	Activity of many Americans
DIETING	Post-New Year's activity
DIETING	Skipping dessert, maybe

Crossword

a puzzle consisting of a grid of squares and blanks into which words crossing vertically and horizontally are written according to clues.