Very! Eating early in the day not only jump starts our metabolism, but also prevents us from having one huge meal at lunchtime due to our extreme hunger.
Let's say you eat dinner at 6pm the night prior, skip breakfast the next day, and have lunch at 12pm. That is an 18 hour gap between eating! You might be thinking, "Well if I'm not eating for 18 hours I most certainly should lose weight, right?"
Unfortunately that is wrong. Fasting for this amount of time prevents the body from producing important enzymes that metabolize fat. If our bodies cannot metabolize fat, we cannot lose weight.