Tink06 rice cakes in themselves aren't very fattening.
However if friend went out last night and had 5-6 G&Ts that is fattening! That was 180 calories a go, so wiped out her 1200-1500 calories a day target. If she had 2, she only had 2-500 calories left for real food for the whole of the day.
She's had say 6 rice cakes and a tub of low fat hummus this morning. We'll assume it's breakfast - again if a snack, it's a massive one.
6 rice cakes we've already worked out as 280 calories. Low fat anything generally isn't that healthy as it's usually had sugar added to make it taste nicer now the fat's been removed. We don't know the size of low fat hummus pot but picked at random because it was the first to come up on myfitnesspal I've gone for a 230g Sainsbury's pot. Which works out as 381 calories.
So her healthy breakfast has worked out as 661 calories. And I haven't included the juice yet, which is massively not recommended for being high in sugar. Bung in another 150 calories on juice and friend has eaten 811 calories on breakfast alone, while thinking she has picked the healthy option. She'd now have to eat lettuce for the rest of the day to come in at her target for weight loss.
I suspect friend is doing a number of things here: not counting calories in alcohol, believing juice is healthy and low calorie, eating too big portions of 'healthy food', not counting snacks. Which is what I did for many years and wondered why I was gaining weight not losing.