I wonder why it's so tough?

Just increase your amount of vegetables to replace most, if not all of the rice. The rest goes to beans and fish / chicken.

Remove all sugar in your diet, which includes any sweet drinks. Don't touch any processed refined carbs, which includes bread and snacks.

It's not tough at all, and in fact being a highly stressed lack of sleep person and with no extra budget for multivitamin, I'd say the no sugar diet has helped me prevent from catching a full blown flu so far.

Well, technically, you can only find the least unhealthy bread. The least unhealthy would be a gluten-free, soaked grains bread which would most likely require self-baking. And the remaining ingredients that would make it unhealthy are the xanthan gum and yeast, which some can't tolerate as well. Best bet is to limit bread consumption to a minimum, the same way you would for sweet desserts.

Try Adventist. I'm a regular for... more than 5 years? The bread is averagely only 30kcal per slice in comparison to say, a slice of Massimo (which is 90 kcal). Besides, it's packed with nutrition. You can get it in Jaya Grocer, Aeon, Cold Storage etc. Giant used to sell them but not anymore. But oh, it costs RM6.60 per loaf.

I guess it should be fine for starters. Can't be any worse than what made you overweight, right? 

BMI is flawed. It's only good for getting a general statistical outlook on large surveys.

Just for example you could be as fat as an obese guy (in terms of muscle mass to fats ratio) but just 50% smaller in overall size.

Well, you can solely use your diet to obtain a good physique. But to perfect it (and expedite the process) you will need to exercise.

Similarly, good nutrition is crucial to keep diseases at bay. But to be considered healthy you'll need exercise.