Introduction Professional diving is an activity that exposes the diver’s body to numerous environmental and physiological challenges. These require adequate physical and mental health conditions as a prerequisite for the task’s safe performance. The diver’s diet is an underestimated risk factor that has not been properly studied so far. Thus, due to lack of dietary recommendations, many times divers make basic dietary mistakes that can lead to undesirable outcomes, from abdominal discomfort to death by drowning.

Objective To determine how food and physiological changes due to immersion and hyperbaric exposure can interfere with diving safety.

Results Food-related factors can lead to life-threatening risk conditions, since situations that would normally be considered just inconvenient and uncomfortable can be potentially fatal when they occur underwater, such as vomiting, for example. Especially considering the diet specific factors: volume of the food, nutritional composition of the diet, and the time interval between the last meal and the dive, the food can be a hazard associated with risks that can compromise the safety in the dive. These risks can be divided into direct - such as hypoglycemia, dehydration, gastrointestinal barotraumas (mainly resulting from aerophagia and gastrointestinal producing conditions), and regurgitation with vomiting or bronchoaspiration - and indirect - such as increased cardiac risk and increased decompression stress (which could lead to decompression sickness despite the correct application of the decompression tables).

Conclusion Healthy eating is a fundamental part of ensuring a healthy lifestyle. Given the particularities imposed by immersion and hyperbaric exposure, the diver’s diet should be considered an important aspect in promoting health and diving safety. Awareness of the risks and knowledge of measures to increase the safety of diving can lead to beneficial changes in habits and, consequently, in the safety of diving operations.