A: It does in fact not matter what time of day you eat. It is however important what you eat and how much you eat and how much physical activity you do during the whole day that determines whether you gain, lose, or maintain weight. If you like snacking late at night, try to keep those snacks small, and low in energy value. Also try to avoid snacking in front of the TV, as one can often overeat when you are distracted by the television.