My opinion is that you sound like you are depriving your body of essential nutrients that your body needs to function properly. I also think you might not be taking in enough calories. Your body is like a car that it needs fuel for it to run and then there is always all the maintenance that goes with keeping that car from stalling and breaking down.
You would benefit your body more by providing it with what it needs. I am not sure if you know how to cook but, I would try spending at least one day and figure out what your body likes. There are things that are good for your tummy and then there are things that are good for your mouth.

I would recommend finding things that are good for your tummy that will satisfy those tastebuds in your mouth. And definitely give your body more fuel to function. Not a good thing to go through your day and realize you have brain fog because you didn't get the proper nutrients and minerals.
Some breakfast ideas would be a bowl of steel cut oats with some fresh strawberries and a sprinkle of splenda and a glass of your 1% milk. Or maybe a whole grain bagel with a few slices of smoked salmon and some stone ground mustard or even some low fat or fat free cream cheese and a small cup of mandarin oranges (packed in water). Or even a fried eggwhite sandwich on whole grain toast and a cup of fresh strawberries and a bit of yogurt mixed with a bit of splenda. Most of these ideas are about 300-500 calories.
Some snack ideas that usually hold me over is a few turkey roll-ups (with diced tomatoes, jalapeno peppers and pepperjack cheese inside). Hummus and veggies are absolutely delish. And if you need a heartier snack I would just pop the roll-ups or the hummus in the microwave for a minute and then it seems like I am eating a meal and my mind is convinced that it will hold me over.
Lunch is an easy one for me..... salad with veggies and then whichever protein I have with it I just heat that up and top my salad with it.... salad and veggies are great fillers... you can get alot of it without all the sodium.
Dinner.... Since I am an atkins follower I usually have one of my oopsie rolls with some sort of protein. I do stay away from sugars, flour, and potatoes.... but we do eat whole grains and can have oats.....
Simply saying you should try and stay away from packaged foods and definitely get in more calories. It's too bad your friend has you questioning your choices.... you are on the right track by acknowledging that she has a problem. Don't let her mistakes become your own. As other's said every body is different.
When I am in weight loss mode I eat around 1900 calories a day. If I want to maintain I am usually around 2600 a day. A calorie is definitely a calorie but would you rather put 1900 calories of cereal in your body or would you rather have 1900 calories of fresh fruit, veggies, whole grains, and protein. The choice is always yours. You are the only one controlling your body.
Again, this is only my opinion. I hope this helps, it was only meant to give you other options. I wish your friend the best of luck and I hope she has a resource to get some help. Maybe let her know you are a subscriber here and maybe she, too, will become better informed on how her body works. I am glad she has a friend like you to help her.
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