The A1 Protein Free Vs Conventional milk study in lactose tolerant and lactose intolerant consumers

Some people feel unwell after drinking regular cow's milk — experiencing symptoms like bloating, gas, and stomach cramps. While this is often blamed on lactose, some research suggests that a protein in standard milk called A1 beta-casein may also play a role. This study compares A1 protein-free milk (which lacks the A1 protein) with conventional milk to see if there is a difference in digestive comfort. Participants — both people who are lactose tolerant and those who are lactose intolerant — will drink each type of milk in separate test sessions, and researchers will measure symptoms as well as biological markers in blood, urine, and stool samples over time. You may be eligible if you are aged 18 to 65, have a body weight over 50 kg, and are in good general health. You must be willing to avoid all dairy products for the duration of the study. People with gastrointestinal conditions (such as inflammatory bowel disease or coeliac disease), dairy allergies, or who are pregnant are not eligible.