I think only experience will answer this question.
I can give you my kit list and overall weight from my camp yesterday.
Karrimor Sf Sabre 45 rucksack. Sack liner.
Toakes TiStand & 650ml pot & small tin alcohol stove, 500ml fuel. Trangia pan&handle
Robens closed cell foam mat, Rab Neutrino 700 sleeping bag, Hilleberg Akto.
1 set of dry clothes including down jacket in a dry bag. This doubles as my pillow.
1L water, 300ml milk, onion, burgers, baps, 2 wheetabix, choc bar, pack of sweets, tea/sugar,
3x torches, book , wet wipes, roll of electricians tape, few lengths of paracord, microfibre cloth, tissue, spoon, spatula, cup, couple of lighters, reading book.
I think that is practically everything I carried and it came in at about 13kg. I'm happy with that as it's practically a full 1 night winter kit.
As TeeDee said, can you lose a few lbs yourself? I weigh, or weighed (I've been exercising more) 100kg. I'm not fat, I've always been in and out of the gym weightlifting but I do carry what I call 'puppy fat' but I'm certain I could lose more weight in body mass than I could in kit.