Asanas unlike physical exercises are not meant for weight loss, but weight loss is a byproduct of adopting a holistic lifestyle. To lose weight, one needs a holistic approach that requires the physical, psychic and dietary dynamics to work in conjunction. When awareness at all levels get sharpened, all the physical body needs automatically reduce. Hunger/thirst reduce, sleep reduces (quality improves), sexual desires reduce, and so the mind can be engaged for higher functions.
What the world today knows and adopts as intermittent fasting was way back a yogic disciple, wherein people followed a yogic diet by consuming only 2 to 3 meals a day at fixed intervals and no munching in between. This sets the body clock accurately for the digestive enzymes to release and function. Yogic diet is believed to be half a portion of solid food, one-fourth is water and one-fourth is left empty for the air (vayu) to circulate and digest the food. Food that is conducive for one’s constitution should be consumed. The effect of yogic diet on the physical and mental well-being is that it leads to healthy thoughts, improved metabolism and drug free life.