Karen Corbin joins me to unpack one of the most fascinating questions in nutrition science right now: can your gut microbiome influence how many calories you actually absorb from food?
We explore what it means for weight management, metabolic health, and long-term disease risk, plus why the future of microbiome research depends on better study designs, more rigorous phenotyping, and a shift from “who’s there” to what microbes are actually doing.
What We Cover
- Can two people eat the same food, yet absorb meaningfully different calories because of their microbiome?
- Why a high-fibre, microbiome-supporting diet may increase faecal energy loss, and what that could mean over time
- Where the “missing” calories might go, including the role of microbial biomass and fermentation
- Why association-heavy microbiome research has limits, and what better human studies need to look like
- Karen’s practical framework: “Have I fed my gut microbiome today?” and the four key upgrades
- What the evidence says about probiotics vs food-first prebiotics for metabolic health
- Why early-life factors matter, but why it is still worth changing your diet today
- Where microbiome science is heading next, including metabolite signatures, objective diet measures, and gut–brain links
Thanks for tuning in. If you found this useful, share it with a friend and try the simple daily question Karen recommends: have you fed your gut microbiome today?
You can keep up with Dr Karen Corbin’s latest research on how diet–microbiome interactions influence human metabolism and energy balance by connecting with her on LinkedIn and exploring her profile at the AdventHealth Research Institute.
- Intro (00:00)
- Can the Gut Microbiome Increase or Reduce Calorie Absorption? (01:02)
- Karen Corbin’s Microbiome Research Journey in Nutrition Science (04:17)
- New Microbiome Experiments That Could Change How We Eat (11:17)
- Energy Balance Explained: Calories, Metabolism, and Weight Gain (18:28)
- How Scientists Study the Gut Microbiome (29:19)
- Is the Gut Microbiome Causing Obesity and Metabolic Disease? (38:54)
- How Medications Like Metformin Affect the Gut Microbiome (43:31)
- Can a High-Fiber Microbiome Diet Reduce Hunger and Cravings? (45:06)
- Liver Fat, Type 2 Diabetes, and Metabolic Dysfunction Explained (50:44)
- Best Diet and Nutrition Strategies for Fatty Liver Disease (56:01)
- How Diet Changes the Gut Microbiome and Metabolism (1:02:27)
- Probiotics vs Prebiotics: What Actually Improves Gut Health? (1:07:08)
- GLP-1 Weight Loss Drugs and Their Effects on the Microbiome (1:13:07)
- Gut Microbiome Metabolites and How They Impact Health (1:16:28)
- Gut-Brain Connection: How the Microbiome Affects the Brain (1:21:57)
- Future of Gut Microbiome Research and Personalized Nutrition (1:30:24)
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More about Karen Corbin
Dr Karen Corbin is an associate investigator and the Obesity Program Lead at the AdventHealth Translational Research Institute. Her program of research focuses on nutrition and metabolism. She studies mechanisms, particularly the gut microbiome, that drive individual susceptibility to metabolic diseases such as obesity, diabetes, and metabolic dysfunction-associated steatotic liver disease (MASLD). Dr Corbin’s research portfolio includes both investigator-initiated and industry clinical-translational studies focused on novel pathogenic mechanisms and therapeutics. Her ultimate goal is to advance clinically relevant research that is poised to transform patient care.
