This is *just* my opinon ... take it for what it's worth.
Any diet that means you have to substitute a real meal with some single item food ... for me, that's not a SUSTAINABLE diet. That means that I might be able to keep it up long enough to lose some weight, but as soon as I'm "done" with the diet part of it, I'd be so sick of the cereal that I'd go back to a regular breakfast and probably gain back at least some, if not all of my weight.
I personally cannot do the exact same one bowl meal over and over and over and over again. I mean, I tend to have the same thing for breakfast (yogurt and fruit) every morning, but I can change it up with the type of fruit, add granola, or oatmeal, etc. ... whatever I want. There's not a *rule* that I can only ever have one thing ... which I would kick against. Cause the minute you tell me I have to have something, I don't want it any more.
The other concern I have here is that if you have 200 cals for breakfast (cereal) and 200 cals for lunch (omelette or whatever) ... are you planning on eating over 1000 cals for dinner? Because at your weight and height, going lower than about 1400 seems like a recipe for disaster - you'll wind up starving and not be able to sustain it long term.
Again, this might work for some people, but for me, this type of diet is not sustainable as a lifetime way of eating.
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