Well... there are a lot of ifs there. Spread throughout the day... and healthy calories. OK, my opinion is that yes, it would be "OK" with your body energy-wise if you were getting enough nutrition in the mix. Say you were using liquids like SlimFast, or protein shakes, for one or more meals or snacks. Your body would probably be getting enough from that. But, you might feel hungry because of lack of bulk, and you might not have enough fiber for healthy bowels.
Nuts are real food, btw! But 1400 cals of nuts wouldn't be very many... Certainly more almonds that most people would want to eat, but it would be something like 8-9 ounces.
It's good to remember that a "calorie" is a unit of measurement from physics--and what happens in the body is much more complex than what comes out of physics experiments. Different types of foods go through different chemical pathways to produce energy. Fats burn differently from sugars, and so on. So, while yes, a calorie is a calorie, not all calories are "created equal" so to speak.
How's that for round about?
Jay