The model may be a bit simplistic, but work by Maurizio decades ago,  
confirmed by Crailsheim and students suggests the following  
dichotomous conditions of workers:

Winter bees: Developed hypopharyngeal glands through their lifespan,  
no feeding or minimal feeding of brood, extended lifespan.

Summer bees: Hypopharyngeal glands develop initially, feeding of brood  
reduces their size, reduced lifespan.

I believe Maurizio showed that in the summer, the equivalent, or close  
to it of winter bees could be produced by simply preventing young  
workers from feeding brood.

The nutrition that larvae receive may be a slight nuance in  
determining physiological state of individual workers.  Very  
simplistically again, actual feeding and rearing of brood is somehow  
modulated to resources available to the colony so as not to produce  
"sub par" workers.

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