RIGHTWHEY - Responders In Gut HealTh Markers Using Fermented WHEY

Investigating the Effect of Fermented Whey Concentrate on Gut Microbial Activity: Does Butyrate Matter?

This 8-week intervention will investigate the effect of daily consumption of a fermented whey concentrate on the short-chain fatty acid profile of faeces in healthy individuals.

This study will help us understand if consumption of fermented foods rich in lactic acid have a beneficial effect on gut health.

The 8-week dietary supplementation trial will investigate the action of exogenous lactic acid consumption on the activity (using short-chain fatty acid) and composition of the gut microbiota.

Participants will be stratified according to their baseline faecal butyrate levels. Therefore volunteers will be asked to provide two faecal samples one week apart. Based on the average absolute level of butyrate in the faecal samples, volunteers will be stratified into either low, moderate or high baseline butyrate levels (detailed in table 1 below). The levels for faecal butyrate for each group are set based on a meta-analysis of 9 human studies of healthy volunteers carried out at the Rowett Institute (n=116; LaBouyer et al, 2016, unpublished). Thresholds were derived from the boundaries of tertiles. Therefore, the moderate butyrate producers represent the middle 33% (see table). Each stratification arm will have a minimum of 17 study volunteers bringing the total to n=51. This has been set to ensure the completion of at least 45 volunteers. To optimise equal gender distribution amongst all study arms a minimum of 5 females and 5 males will be recruited for each arm.

Stratification Butyrate range Low ≤13 mM Moderate butyrate 13 - 20mM High butyrate ≥20mM

Primary and secondary outcomes will be analysed between the low and high butyrate producing groups as well as the overall group effect on everyone.

Inclusion Criteria:

• i. Men and women aged 18-68 years; BMI ranging from 18-35 kg/m2; measured at the screening visit

Exclusion Criteria:

• i. smokers
• ii. subjects with: diagnosis of diabetes, pregnant, hypertension, renal, hepatic, haematological disease, coronary heart disease or any gastrointestinal disorder
• ii. unsuitable veins for blood sampling;
• iii. inability to speak, read and understand English.
• iv. Use of antibiotics within the last 3 months will automatically exclude volunteers.
• v. Vegans. Fermented whey concentrate, (FWC), is derived from milk (animal product) which excludes potential participants adhering to a vegan diet.
• vi. allergy to any of the following: cow milk, lactose, casein, whey, sucralose, acesulfame K, citric acid, potassium benzoate, fruit flavourings.