AE	Adverse Event
AMX	Amoxicillin
AP	Acute Pancreatitis
BBB	Blood–Brain Barrier
BCAA	Branched-Chain Amino Acids
BCFA	Branched-Chain Fatty Acids
BDNF	Brain-Derived Neurotrophic Factor
BMI	Body Mass Index
BM	Bowel Movements
CD	Crohn’s Disease
CeD	Celiac Disease
CLA	Conjugated Linoleic Acid
CRP	C-Reactive Protein
DP	Degree of Polymerization
FOS	Fructo-oligosaccharides
GABA	Gamma-Aminobutyric Acid
GFD	Gluten-Free Diet
GI	Gastrointestinal
GOS	Galacto-Oligosaccharides
HbA1c	Glycated Hemoglobin
HFD	High-Fat Diet
HMOs	Human Milk Oligosaccharides
HOMA	Homeostatic Model Assessment
HPA axis	Hypothalamic–Pituitary–Adrenal Axis
IBD	Inflammatory Bowel Disease
Ig	Immunoglobulin
IL	Interleukin (e.g., IL-1, IL-6, IL-10)
ISAPP	International Scientific Association for Probiotics and Prebiotics
ITF	Inulin-Type Fructans
LOS	Length of Hospital Stay
mDC	Myeloid Dendritic Cell
MetS	Metabolic Syndrome
MSAP	Moderately Severe Acute Pancreatitis
NK cell	Natural Killer cell
NS	Not Significant
OB	Obese
OW	Overweight
PAC-QoL	Patient Assessment of Constipation Quality of Life
QoL	Quality of Life
RCT	Randomized Controlled Trial
RS	Resistant Starch
RT	Radiotherapy
SCFA(s)	Short-Chain Fatty Acid(s)
SCCAI	Simple Clinical Colitis Activity Index
SGD	Score of Gut Dysfunction
T1D	Type 1 Diabetes
T2D	Type 2 Diabetes
TNF-α	Tumor Necrosis Factor-Alpha
UC	Ulcerative Colitis
XOS	Xylo-Oligosaccharides