NTP Gut Health & Microbiome 3 — Questions and Answers
Question 1: Which nutrient is most critical for maintaining the structural integrity of intestinal tight junctions?
- Vitamin C
- Zinc (Correct answer)
- Iron
- Vitamin B12
Correct answer: Zinc
Zinc is essential for tight junction protein synthesis and has been shown to reduce intestinal permeability when deficient.
Question 2: Lipopolysaccharide (LPS) endotoxin is primarily derived from which bacterial type?
- Gram-positive bacteria
- Gram-negative bacteria (Correct answer)
- Fungi such as Candida
- Archaea like methanogens
Correct answer: Gram-negative bacteria
LPS is a component of the outer membrane of gram-negative bacteria and can trigger systemic inflammation when it translocates into circulation.
Question 3: A client eating a low-fiber Western diet is most likely to show decreased levels of:
- Zonulin
- Butyrate-producing bacteria (Correct answer)
- Candida species
- LPS endotoxin
Correct answer: Butyrate-producing bacteria
Fiber-fermenting, butyrate-producing bacteria such as Faecalibacterium prausnitzii decline significantly on low-fiber diets.
Question 4: The enteric nervous system (ENS) is often called the 'second brain' because it:
- Controls higher cognitive functions independently
- Can function autonomously with over 500 million neurons regulating gut motility and secretion (Correct answer)
- Produces melatonin exclusively for sleep regulation
- Directly controls the hypothalamic-pituitary axis
Correct answer: Can function autonomously with over 500 million neurons regulating gut motility and secretion
The ENS contains approximately 500 million neurons embedded in the gut wall and can operate independently of the central nervous system.
Question 5: Which fermented food is richest in Lactobacillus species beneficial for vaginal and gut microbiome?
- Kombucha
- Miso
- Yogurt with live cultures (Correct answer)
- Apple cider vinegar
Correct answer: Yogurt with live cultures
Yogurt with live active cultures is one of the richest dietary sources of Lactobacillus species, which support both gut and vaginal microbiome health.
Question 6: Intestinal dysbiosis can contribute to mood disorders primarily through which mechanism?
- Altered production of neurotransmitter precursors and inflammatory cytokines affecting the gut-brain axis (Correct answer)
- Direct bacterial invasion of the cerebral cortex
- Reduced absorption of fat-soluble vitamins only
- Increased gastric acid production irritating the vagus nerve
Correct answer: Altered production of neurotransmitter precursors and inflammatory cytokines affecting the gut-brain axis
Dysbiosis alters serotonin precursor production (e.g., tryptophan) and increases pro-inflammatory cytokines that signal the brain via the gut-brain axis.
Question 7: Which test is considered the gold standard for diagnosing SIBO?
- Stool culture
- Lactulose or glucose breath test (Correct answer)
- Endoscopic biopsy of small intestine
- Comprehensive stool analysis (CSA)
Correct answer: Lactulose or glucose breath test
Lactulose or glucose hydrogen/methane breath tests detect bacterial fermentation gases in the small intestine and are the standard non-invasive SIBO diagnostic.
NTP Gut Health & Microbiome 3
Which nutrient is most critical for maintaining the structural integrity of intestinal tight junctions?