And you are dairy-free as well, Clare? I ask because there are many things to have for breakfast that are low or no fibre, besides Rice Krispies. And you could ‘fortify’ with vitamin and mineral supplements, yes?
I suspect that the high sugar meal you are eating in the morning is setting you up for your desire to eat more, and I guess you’re making similar choices for lunch… and so it continues, and you find “the desire is building all day”.
Your first step would be to recognise the outcomes of your choices at breakfast (and maybe lunch too). The best way to do that would be to try eating something quite different (and low in sugar) but I do wonder if that’s something you will consider.