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