Optimal Nutrition for Diving 

A healthy diet is an asset for safe scuba diving as well as a beneficial lifestyle. We should harness the nutrients from a balance of carbohydrates, fats, and proteins. © DARIA KULKOVA/ISTOCK

Scuba diving demands not only physical fitness but also proper nutritional preparation. Like with any activity, we expend energy while diving; surprisingly, the energy required for routine recreational diving is somewhat moderate. Under unusually strenuous recreational conditions, however, it’s possible to burn more than 500 calories. 

There is no need to eat more in preparation for diving. Following a regular diet of foods that provide nutritional value is sufficient.

Our bodies harness the nutrients we ingest for energy, with carbohydrates, fats, and proteins being the three primary sources. Carbohydrates, often referred to as sugars, are vital for endurance and are the preferred energy source for athletes and divers.

Carbohydrates come in two categories: simple and complex. Simple sugars (such as glucose and sucrose) are found in honey, fruit juices, and junk food. The digestive system rapidly absorbs these sugars, leading to a spike in blood sugar levels and subsequently triggering insulin release. Excessive consumption of simple sugars can result in sudden drops in blood sugar levels, appetite stimulation, and unhealthy weight.

In contrast, complex carbohydrates — found in foods such as peas, beans, whole grains, and vegetables — release sugars into the bloodstream more gradually, preventing sudden spikes and crashes in blood glucose levels.

Carbohydrates serve various functions, including providing fuel in the form of glucose for muscles, the brain, and other organs. Additionally, the liver and muscles store the carbohydrate glycogen for energy during intense exercise. Each gram of carbohydrate provides 4 calories.

Fats, another essential dietary component, are the body’s primary energy storage and play crucial roles in thermal insulation, organ protection, and cell structure. We generally categorize them as “good” (unsaturated) and “bad” (saturated and trans) fats. Each gram of fat supplies 9 calories.

Proteins are indispensable for tissue formation, energy production, injury repair, and nutrient transportation throughout the body. Proteins consist of nine essential amino acids we must obtain through diet because the body does not produce them. Every gram of protein provides 4 calories.

Water is the human body’s most abundant component, constituting between 50 and 70 percent of total body weight. It plays pivotal roles in digestion, waste excretion, blood circulation, and temperature regulation. 

Woman hydrating before diving
Hydration can reduce the risk of decompression sickness and may also minimize cramps and fatigue. © STEPHEN FRINK

Proper hydration before and after diving is important for preventing dehydration’s adverse effects on physical performance and eliminating dissolved inert gases from body tissues. Dehydration can lead to decreased blood fluid volume, further underscoring the importance of staying adequately hydrated. It is advisable to gradually consume fluids during the day, and you may need more than usual if you are exercising or the weather is hot and humid. Proper hydration may also prevent muscle cramps and fatigue and reduce the risk of decompression sickness. The food you eat also provides a large percentage of your daily fluid requirements. Remember that overhydration can be a factor in the development of pulmonary edema.

It is best to avoid overeating, especially when diving. On the day of the dive, consider including foods rich in complex carbohydrates to maintain steady energy levels. Many people avoid heavy, fatty meals before diving to mitigate gastrointestinal discomfort. Refrain from any alcohol consumption since it affects cognitive abilities and can contribute to dehydration.

You might have an increased hunger sensation after a dive, possibly due to the need for water, but avoid overeating to satisfy that feeling. Good food choices include rice, pasta, potatoes, and fruits. Avoiding evening alcohol consumption, which can exacerbate dehydration by inhibiting the antidiuretic hormone, is especially helpful if you plan to dive the next day. 

Following these recommendations will optimize your nutrition and help ensure a safe and enjoyable dive experience.

© Alert Diver — Q1 2024