To confirm and extend previous research concerning glucose and lactate in vitreous humour, we investigated a randomly selected study population of 271 forensic cases. On the whole, we find our results agree with those of previous studies, but we add certain observations. First, when we considered the sum value of glucose and lactate in the vitreous humour, we found that not only diabetes patients are included in the higher range group (values ≥430 mg%): intensive reanimation or prolonged or intense agony should also be taken into account. Indeed, when we split our study group into acute agony and prolonged agony subgroups, we noticed a statistically significant difference; persons dying after protracted agony showed a higher sum value, which can be explained in terms of biophysical dynamics. Second, a positive correlation was found between the lactate and the sum values on one hand, and the postmortem interval on the other. However, the vitreous glucose, lactate, and sum values are so dispersed that a precise determination of the postmortem interval cannot be obtained on the basis of these parameters. Additionally, we compared several causes of death, but unfortunately, we did not manage to reveal that some causes of death were specifically limited to high or low concentrations. Indeed, the statistically significant differences in sum values could easily be explained by factors such as intensity of agony, reanimation attempts, or iatrogenic interventions (e.g., glucose infusions). Nonetheless, when the death scene as a whole is unclear or confusing, analysis of the vitreous humour can provide some insights, provided that the other autopsy findings are also taken into consideration.