As long as the overall trend is down, then falling off the wagon is forgivable. Knowing that it is ok to "occasionaly" sin makes it easier to resist the temptations much more often. Maybe the results are a tad slower but they still come and your mental health is not tied up in knots lusting after something snackable. My experience anyway.

Pass no temptation lightly by, for one never knows when it may pass again!