Effects of a Microalgae Extract Dietary Supplement on Gut Health, Anxiety, and Immune Function

1. Total number of subjects who will be approached (including screen fails, controls, and subject withdrawals) to reach enrollment numbers for the lifetime of the study for this investigator's site: 100-125
2. Total number of subjects to be enrolled at this site: The investigators plan to enroll 60 participants for a target completion of 50 participants (25/arm). Enrolling 60 individuals allows for a conservative 20% attrition rate. This is the first human study of the commercial product Tetrasol, which looks at intestinal health outcomes. Therefore, this will be considered a pilot study, and the data will allow us to determine the appropriate sample size for a statistically powered study to identify differences in gastrointestinal health between Tetrasol consumers and placebo.
3. Brief Description/justification for the proposed sample size in lay terms:

The investigators have no human data related to our primary outcome measures for this product. Therefore, investigators propose a pilot study of 25 individuals in each study group. 4. Before the start of enrollment, 60 subjects will be randomly assigned using a random number generator. Upon enrollment, each subject will be assigned either intervention A or B, according to the randomization chart. 5. The study will be a double-blind, placebo-controlled study. Neither the investigators nor the participants will have knowledge of the contents of the capsules. The capsules will be labeled by Microphyt personnel who are not directly involved in the study, and they will maintain the code. Unlike the intervention capsules, the placebo does not contain rapeseed oil and calcium, as the product manufacturer developed these formulations. They wished to keep the placebo formula the same as the formula previously used in their in vitro assays and other clinical work for more equitable comparisons across studies. CSU clinical personnel will administer the two intervention capsules to the subjects according to the randomization strategy and will not be provided with the code for intervention groups until after all data analysis has been completed. In a very unlikely case of a severe adverse event (which is an event that requires the subject's hospitalization), the medical personnel will be provided information about the content of the capsules taken by the participant directly by the Microphyt personnel. The code will not be broken to the investigators until after all data has been analyzed and submitted as a preliminary report.

A. Recruitment:

Recruitment advertisements will be placed in the Coloradoan and other newspapers/newsletters as relevant and will be sent out electronically through the CSU faculty and administrative professionals list on the CSU State Classified list. The investigators will reach out to graduate students and undergraduates by sending the recruitment email to the appropriate administrative personnel in each department (i.e., Grad coordinators and academic success coordinators) and have them forward the study information to their students. Flyers will be posted and distributed throughout the CSU campus and at targeted locations within the community, including UC Health doctor's offices. Flyers will be sent out as direct mailers to individuals in the community; their names and addresses will be purchased from a reputable company that provides names and addresses of individuals in this age range (Alesco Data, http://www.alescodata.com/). To increase participant diversity, investigators will also reach out to student groups on campus, including the Adult Learner and Veterans Services, Asian Pacific American Cultural Center, Black/African American Cultural Center, El Centro, Native American Cultural Center, Pride Resource Center, and Women and Gender Advocacy Center, and cultural groups off campus such as the BIPOC Alliance. Finally, investigators will also contact individuals in our clinical database who participated in previous studies and indicated a willingness to be contacted for future studies.

B. Screening Procedures or Interview/questionnaire: After a preliminary telephone screening (questionnaire attached), volunteers will undergo an in-person screening (visit 1) and provide written informed consent. A questionnaire will assess medical and health history and demographic information, followed by an anthropometric assessment (height, weight, waist, and hip circumferences).