I was raised on a very high-carb diet and I lived that way as an adult for 20 years. I actually thought it was healthy to eat that way! I'd roll up spaghetti in bread and have "spaghetti sandwiches", not realizing that my body would metabolize it as mostly pure sugar! I used to congratulate myself for choosing pancakes and toast over bacon and eggs!
Anyway, I am cured of all that and I will now be a big proponent of low-carb eating.
You say it is too hot to walk where you are but what about getting up early in the morning to walk before the heat of the day sets in? That is actually the best time to get in your excercise as your metabolism will be spiked for a good part of the day.
Up here in New England, it is rarely too warm to walk. In fact, it was in the low 50s this morning and I could see my breath. But I'll have a real obstacle in the winter when it is often below zero (at least windchill-wise).
Even better is to do that early morning exercise BEFORE eating anything at all (i.e. in a "fasting" state). Does wonders for fat metabolism. I assume that is your practice??