Resistant starch (RS), a type of dietary fiber, was shown to have beneficial effects on human health through its impact on microbes present in the intestine. However, the effects of RS on the gut microbiota and in turn, on human health, can vary between individuals. Consequently, everyone may not reap the same health benefits by eating high amounts of RS. Factors predicting how an individual's gut microbes as well as the beneficial metabolites produced by these microbes respond to RS supplementation would be helpful in developing precision nutrition approaches that maximize the benefits of dietary fiber intake. The objective of this study was to evaluate candidate predictors of gut microbiota response to RS supplementation.

Inclusion Criteria:

• Above 18 years of age
• Willing to consume the supplements provided throughout the duration of the study

Exclusion Criteria:

• History of diabetes, prediabetes or impaired glucose tolerance.

• Existing, UNTREATED, thyroid condition.

• Usage of systemic antibiotics (intravenous injection, intramuscular, or oral) within 6 months prior to the study.

• Acute disease at the time of enrollment.

• Chronic, clinically significant pulmonary, cardiovascular, gastrointestinal, hepatic, or renal functional abnormality.

• History of active UNTREATED gastrointestinal disorders or diseases including:

  i. Inflammatory bowel disease (IBD) ii. Ulcerative colitis (mild-moderate-severe) iii. Crohn's disease (mild- moderate-severe) iv. Indeterminate colitis v. Irritable bowel syndrome (IBS) (moderate-severe) vi. Persistent, infectious gastroenteritis, colitis or gastritis vii. Persistent or chronic diarrhea of unknown etiology viii. Clostridium difficile infection (recurrent) ix. Chronic constipation

• Suspected state of immunosuppression or immunodeficiency including HIV.

• History of bariatric surgery.

• Pregnant or lactating women.