This research aims to develop a better understanding and clinical knowledge of the effects of a plant based diet on severity and daytime sleepiness in Obstructive Sleep Apnea.

Inclusion Criteria:

• Daytime sleepiness with ESS score ≥ 5.
• Patient's prior sleep study with AHI between ≥ 10 and ≤ 45 (4% scoring criterion).
• On treatment for OSA, failed or not willing to use all other OSA treatment options
• Has access to a weight scale at home or able to come into the Sleep Clinic to be weighed after the 8-week plant-based diet period.

Exclusion Criteria:

• Pregnancy or lactation.
• Current use of a vegan diet.
• BMI ≤ 22.
• Complex, central sleep apnea.
• Pre-existing significant degree of cardio-pulmonary disease-heart failure with reduced EF of 35 or lower, unstable arrythmia, severe degree of pulmonary hypertension, severe degree of obstructive or restrictive lung disease including COPD and Interstitial lung disease.
• On weight loss medications or starting new exercise regimen during the 8-week plant-based diet period.