The quality of a domestic cat’s diet affects his or her desire to hunt
It would seem that if you feed your cat a poor quality dry food diet she may be more inclined to hunt for prey to supplement her diet. The supplementation of her diet would be purely instinctive but lead her to hunting more often.

Cat’s diet drives her to find protein supplement! Picture in public domain.
Studies
In a fairly recent study from Chile, cats fed on household scraps were found to be four times more likely to kill and eat a mouse when compared to cats fed on modern, balanced cat food.
In another study, cats eating low quality cat food would stop eating to chase and kill a rat. However, when the cats were eating fresh salmon they ignored the same opportunity to hunt.
It is suggested, therefore, that cats fed on nutritionally unbalanced cat food are more strongly motivated to hunt by the impulse that they need to supplement the diet to maintain their health.
The nutritional requirements of the domestic cat are very specialised and can only be met from a domestic cat’s prey, such as a mouse, or well produced, nutritionally balanced commercial cat food.
Carbohydrates
Also, scraps of low quality cat food tend to be higher in carbohydrates. In eating such a diet every day these carbohydrates may give a cat a craving for food rich in protein which equates to meat – the flesh of an animal.
Cat guardians are less likely to purchase low quality cat food today compared to half a century ago but there are some poor quality cat foods around particular of the dry variety. Therefore this information may be useful for some people.
Poor diet – stray cat
It may be that neglected cats being fed a very poor diet are driven from their home by the need to supplement their diet by hunting. It is perhaps not beyond the bounds of possibility that some domestic cats end up being stray cats because they were neglected with respect to their diet.
Once a domestic cats acquires the habit of hunting he or she may be slow to unlearn the habit which is a factor in cat “ownership”. Most cat owners do not like their cat hunting even though it is completely natural. As the environment becomes more important to people, domestic cat hunting becomes more of an issue.
Source: Cat Sense by Dr Bradshaw.