A1-Free vs. Conventional Milk Metabolic Response Study

Summary

This study will examine how different types of milk affect blood sugar and insulin responses after eating. Specifically, the study compares milk that contains only A2 beta-casein protein (A1-free milk) to conventional milk, which contains both A1 and A2 proteins.

Participants will complete four study visits in which they will consume different milk-based beverages. These include lactose-containing milk and lactose-free milk followed by a lactose drink given later. Blood samples will be collected over several hours to measure glucose and insulin responses. Breath tests and questionnaires will also be used to assess digestion and gastrointestinal symptoms.

The goal of this study is to determine whether milk protein type influences metabolic responses and whether consuming lactose-free milk affects how the body processes lactose when it is consumed later.

Conditions

• Postprandial Glucose Response
• Insulin Response
• Lactose Digestion
• Postprandial Metabolism

Interventions

DIETARY_SUPPLEMENT

Lactose-Containing A1-Free Milk

A lactose-containing milk beverage containing A2 beta-casein and no A1 beta-casein, consumed during one experimental study visit.

DIETARY_SUPPLEMENT

Lactose-Containing Conventional Milk

A lactose-containing conventional milk beverage containing both A1 and A2 beta-casein, consumed during one experimental study visit.

DIETARY_SUPPLEMENT

Lactose-Free A1-Free Milk With Delayed Lactose Drink

A lactose-free A1-free milk beverage consumed at the start of the study visit, followed by a lactose drink administered 60 minutes after milk consumption. The lactose drink is matched to the amount of lactose expected in the milk serving.

DIETARY_SUPPLEMENT

Lactose-Free Conventional Milk With Delayed Lactose Drink

A lactose-free conventional milk beverage containing both A1 and A2 beta-casein consumed at the start of the study visit, followed by a lactose drink administered 60 minutes after milk consumption. The lactose drink is matched to the amount of lactose expected in the milk serving.

Sponsors & Collaborators

• Purdue University

  lead OTHER

Principal Investigators

• Dennis A Savaiano, PhD · Purdue University

Study Design

Allocation

RANDOMIZED

Purpose

OTHER

Masking

TRIPLE

Model

CROSSOVER

Eligibility

Min Age

18 Years

Max Age

65 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2026-06-15

Primary Completion

2026-10-31

Completion

2027-01-31