In a classic experiment, obese patients whose daily caloric intake was dramatically reduced lost only 6 percent of their weight. this limited weight loss was due, at least in part, to the fact that their dietary restriction led to

Restriction of food turns your body into a fat storing machine rather than a fat burning machine. When your body stops getting the calories it needs it automatically thinks "Idk when my next meal is" causing the action of storing rather than burning. Unless the restriction is so severe that your body has to survive off the fat within it.