The answer to this question would be: 12 percent for women.
Losing too much fat can be dangerous. Fat is commonly used for making hormone, insulating heat and as food storage. If you doesn't have enough fat, some hormone might not be produced. Your body also will hardly fight against cold as its heat insulation is depleted so you will prone to hypothermia. The recommended limit for body fat is higher in women which were around 10-13% and 3-5% in men.