Milk protein showdown: does A1-Free milk beat conventional for blood sugar?

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Ability/desire to provide informed consent * Are between 18 and 65 years of age * Are generally healthy, with no known metabolic or gastrointestinal conditions that would affect digestion or metabolism * Are willing to consume milk-based beverages and lactose-containing drinks as part of the study * Are willing to fast overnight (approximately 10-12 hours) prior to study visits and follow study instructions (e.g., diet and activity restrictions) * Are willing to attend all study visits and complete all study procedures (blood draws, breath tests, urine samples, questionnaires) * Are able to understand and provide written informed consent in English. Exclusion Criteria: * You have a known allergy to milk or dairy products * You are currently pregnant, planning to become pregnant, or breastfeeding * You currently smoke or have used tobacco or nicotine-containing products within the past 3 months * You have a history of excessive alcohol use within the past 30 days * You have been diagnosed with diabetes (Type 1 or Type 2), prediabetes, or other metabolic conditions that affect glucose or insulin responses (such as insulin resistance, metabolic syndrome, or polycystic ovary syndrome \[PCOS\]) * You have a history of gastrointestinal conditions that may affect digestion or absorption (such as inflammatory bowel disease, Crohn's disease, ulcerative colitis, celiac disease, or severe irritable bowel syndrome) * You have had gastrointestinal surgery that alters normal digestive function (such as bariatric surgery or gastric bypass) * You have other medical conditions that may affect digestion or interfere with study results (such as Past or present: Organ transplant, chronic pancreatitis, pancreatic insufficiency, symptomatic biliary disease, Celiac disease, chronic constipation, diverticulosis, inflammatory bowel disease (IBD), ulcerative colitis (UC), Crohn's disease (CD), small intestine bacterial overgrowth syndrome (SIBO), gastroparesis, gastro-esophageal reflux disease (GERD), Irritable Bowel Syndrome (IBS) or any other medical condition with symptoms that could confound collection of adverse events.) * You have used medications or supplements known to affect glucose metabolism, digestion, or gastrointestinal function within the following timeframes prior to enrollment: * Within 4 weeks: insulin, metformin, GLP-1 receptor agonists, corticosteroids, digestive enzymes, fiber supplements, and all oral or IV antibiotics * Within 2 weeks: bismuth-containing compounds (e.g., Pepto-Bismol) and proton pump inhibitors or acid suppressors (e.g., omeprazole \[Prilosec\], lansoprazole \[Prevacid\], esomeprazole \[Nexium\], pantoprazole \[Protonix\], rabeprazole \[Aciphex\]) * Within 1 week: laxatives and stool softeners (e.g., Miralax, Colace, senna, lactulose, Citrucel, Metamucil, Fibercon), probiotics and prebiotics, gastrointestinal motility agents (e.g., Reglan, Linzess, Amitiza), and antidiarrheal medications (e.g., loperamide \[Imodium\], Lomotil) * You have had a recent infection within the past 30 days * You have been diagnosed with Human Immunodeficiency Virus (HIV), hepatitis B, or hepatitis C * You are currently undergoing chemotherapy * Height: \_\_\_ Weight: \_\_\_ BMI: \_\_\_ Weighing \<16.5 kg or Body mass index \> 35 kg/m2 * You have participated in another clinical trial or used an investigational product within the past 30 days * You have any other condition that, as determined by the study team, would make participation unsafe or interfere with study results