Animal and Microbial-based Dietary Protein Efficiency in Adults

Inclusion criteria

• Healthy, male and female, recreationally-active participants.
• Healthy will be defined as screened by the PAR-Q+ (Appendix B) and The Physical Activity Readiness Questionnaire (Appendix C).
• Participants will be aged 18-45 years old.
• Participants are willing to abide by the compliance rules of this study.
• Self-reported regular menstrual cycle (25-35d) within the last 3 months (female participants).
• Use of monophasic combined oral contraceptives (COC) containing 21 active pills (e.g., Yaz, Marvelon, Cyclen, etc.; the brand of COC will be recorded) (female participants).

Exclusion criteria

• Inability to adhere to any of the compliance rules judged by principal investigator (e.g. dairy protein or yeast allergy).
• Self-reported regular tobacco use.
• Self-reported illicit drug use (e.g., growth hormone, testosterone, etc.).
• Individuals who have participated in studies within the past year involving any of the stable isotopes in the study.
• Use of multiphasic COCs due to the difficulty of controlling for hormonal fluctuations in such formulations (female participants).
• Use of COCs containing >21 active pills per cycle due to potential differences in their effect on metabolism (female participants).
• Use of other forms of hormonal contraception (e.g., progestin-only pill, hormonal IUD, intravaginal ring) (female participants).
• Not currently or previously (in the past 6 months) on a vegan diet