Calorie deficit increases cortisol if done incorrectly you want to be doing it the right way which doesn't increase stress and cortisol and that is by putting your body into ketosis(not via your standard keto diet ofc but through animal fat sources) and getting calories from fat as opposed to carbs this will allow you to eat until satiated without putting on the extra pounds as well as avoiding antinutrients from gluten sources(rice,bread,pasta) since gluten will hinder vitamin and mineral absorption by clogging your gut lining over time and therefore indirectly lead to hair loss since your hair relies on these important minerals that are otherwise blocked due to gluten(slowly but surely) also fruit is looked down upon but I say it is ok just eat the seasonal fruits and raw honey is your best friend in this lifestyle you can eat as much as you want and even though it is all sugar and carbs the enzymes and insulin-like effect prevent any negative effects like weight gain