Comparative effects of A1 versus A2 milk on gastrointestinal symptoms and systemic exposure to beta-casomorphin-7 (BCM7)

• Register: ANZCTR
• Last refreshed on: 10 February 2020
• Main ID: ACTRN12611000740998
• Date of registration: 14/07/2011
• Prospective Registration: Yes
• Primary sponsor: Curtin University of Technology
• Public title: Comparative effects of A1 versus A2 milk on gastrointestinal symptoms and systemic exposure to beta-casomorphin-7 (BCM7)
• Scientific title: Adults and the effect of A1 versus A2 milk consumption on gastrointestinal symptoms and systemic exposure to beta-casomorphin-7 (BCM7)
• Date of first enrolment: 13/02/2012
• Target sample size: 40
• Recruitment status: Completed
• URL: https://anzctr.org.au/ACTRN12611000740998.aspx
• Study type: Interventional
• Study design: Purpose: Treatment; Allocation: Randomised controlled trial; Masking: Blinded (masking used);Assignment: Crossover;Type of endpoint: Efficacy;
• Phase: Not Applicable

Countries of recruitment

Australia

Contacts

• Name: A/Prof Assoc Prof Sebely Pal

• Name: A/Prof Assoc Prof Sebely Pal

Key inclusion & exclusion criteria

Inclusion criteria: Caucasian
Do not drink more than 1 serve milk/day
Those who report lactose intolerance but have not received medial diagnosis
Willing to consume milk for 8 weeks
Able to sign and understand informed consent
Exclusion criteria: Milk allergy
Diagnosed lactose intolerance
Pregnancy and lactation
Cardiovascular event in the last 6 months
Current, habitual opioid consumption
Antibiotic treatment within the last 8 weeks prior to screening
Immunosuppressive medications or anti-inflammatory drugs within the last 4 weeks prior to screening

Age minimum: 18 Years
Age maximum: 65 Years
Gender: Both males and females

Health Condition(s) or Problem(s) studied

Oral and Gastrointestinal - Normal oral and gastrointestinal development and function

Diet and Nutrition - Other diet and nutrition disorders

Gastrointestinal symptoms related to milk intolerance;
Gastrointestinal symptoms related to milk intolerance

Intervention(s)

This will be a randomised, crossover study over an 8 week period consisting of 2 weeks of an initial washout. Following washout, 40 participants will be randomised to either the A1 milk or A2 milk group (Crossover 1), with 20 in each group. This is then followed by another 2 weeks washout after which Subjects will then start the alternative A1 or A2 milk Intervention for another 2 weeks intervention (crossover2).

During washout, participants will consume their normal diet (excluding all dairy) and use rice milk and rice yoghurt alternatives to replace habitual daily dairy intake.

Intervention consists of either:
1) a normal diet (excluding all dairy) + 750mL A2 beta-casein protein containing milk consumed in 3 serves daily (~7-8g A2 type beta-casein/day)
or
2) Normal diet (excluding all dairy) + 750mL A1 containing milk per day, which is equivalent to ~7-8g A1 type beta-casein/day;

Milk will be given as UHT long life, skim milk (A2 Dairy Products Australia)
Average composition:
energy 189kJ/100mL
total protein 3.1g/100mL
total fat 0.1g/100mL
carbohydrate (including lactose) 5.2g/100mL

Primary Outcome(s)

Gastrointestinal symptom management.
Participants will record gastrointestinal symptoms of intolerance in their Symptom Report Diary and daily bowel movement frequency/stool consistency using the Bristol Stool Scale.[Symptoms recorded during each 2 week intervention period]

Secondary Outcome(s)

Measurement of gastrointestinal tract permeability from a dual sugar test and urine analysis[At the end of each 2 week intervention period]

Measurement of gut inflammation from analysis of faecal calprotectin to investigate possible precursors to BCM-7 effects[At the end of each 2 week intervention period]

Investigation of the presence of BCM-7 in serum from fasting and postprandial blood samples[At the beginning and end of each 2 week intervention period
1 hour postprandial sample after consumption of 500mL of milk intervention at the end of each 2 week intervention period]

Secondary ID(s)

Nil

Source(s) of Monetary Support

A2 Dairy Products Australia

Ethics review

Status: Approved
Approval date: 04/10/2011
Contact:

Curtin University Human Ethics Committee

Results

• Results available: Yes
• Date Posted: 05/02/2020
• Date Completed: 17/08/2012