So here are some truths.
- People are not walking math formulas whereby if they have 3,500 more or less calories than they burn they'll gain or lose a pound.
- 3,500 calories of one food or type of food will likely have a different impact on health, hunger, thermic effect, and weight than 3,500 calories of another food or type of food.
- Different people have different caloric efficiencies whereby they are seemingly able to extract more calories from food or reserves than others and lose weight with more difficulty (and gain with greater ease).
From a weight management perspective, the currency of weight is calories. While exchange rates undoubtedly do vary between foods and between individuals, you'll always need your own personal deficit to lose, and surplus to gain.
All other discussion, while certainly academically interesting, given there are no other alternate measures available to track, or tests to determine individual responses to different calorie sources, serves to foment confusion.
If weight's your concern, more important than anything else is finding a life that you enjoy that contains fewer calories than before. Getting stuck in the minutia of what type of calories may lead to an every so slightly faster or greater loss, rather than truly crafting a life that's enjoyable (and hence sustainable), might help in the short run, but will almost certainly defeat you in the long.