Ketogenic Diet for Reduction of CNS Oxygen Toxicity in Working Divers

Ketogenic Diet for Reduction of Oxygen Toxicity in Working Divers

The purpose of this research study is to understand the effect of nutritional ketosis on CNS oxygen toxicity in undersea divers. The investigators hope this will provide a starting point to develop methods for improving the safety of Navy divers, warfighters and submariners.

Participants in the study will undergo a physical exam and testing as well as training on cognitive testing software as part of the screening process. Eligible subjects will be assigned a normal diet or a ketogenic diet (a diet high in fat/protein and low in carbohydrates) for three days before testing. Subjects will be immersed in water to the shoulders, inside a hyperbaric (high pressure) chamber while breathing 100% oxygen at increased atmospheric pressure, and doing cycling exercise. Testing on the cognitive software, as well as blood sampling and physical monitoring will be done while in the chamber. All tests and procedures will be completed again at least one week later with the diet not assigned for the first session.

Inclusion Criteria:

• Males & females between 18 and 50 years old
• Able to pedal a bicycle ergometer continuously for 15 minutes
• Non-smoker
• No history of cardiovascular disease, including coronary artery disease, valvular disease, cardiomyopathy or hypertension.
• No history of lung disease

Exclusion Criteria:

• Prolonged QTc on initial ECG

• Currently pregnant or attempting to become pregnant.

• Have a history of:

  1. Smoking
  2. Coronary artery disease
  3. Hypertension
  4. Seizures
  5. Exercise intolerance
  6. Psychiatric disorder
  7. Previous pneumothorax or pneumomediastinum
  8. Hypo or hyperglycemia
  9. Diabetes

• Regularly take any medications which may alter heart rate, blood pressure, neurotransmitter function, mood or affect.