Does Galactooligosaccharide Enhance Nutrient Availability

University of Bath30 enrolled

Overview

Current evidence suggests that the amount of ingested carbohydrate that we can use for energy during exercise is limited by absorption levels in the gut. Thus, strategies to increase the amount of ingested carbohydrate our body can use are of great interest. Recent evidence has shown we may be able to use more of the ingested carbohydrate during exercise when supplementing with probiotics ("good bacteria for our gut). It is currently unknown whether the food for these "good" bacteria (known as prebiotics) can induce a similar effect. Therefore, the purpose of this study is to understand if supplementation with the prebiotic Galactooligosaccharide (onwards referred to as BIMUNO®) can increase the use of ingested carbohydrate during exercise. We also aim to understand if BIMUNO® can enhance the availability of other nutrients, such as vitamins and minerals. Participant will attend 8 laboratory sessions at the University of Bath. The first session is a screening visit lasting no more than 30 minutes. This can take place online, over the phone, or in-person, and the remaining 7 sessions will take place in a University of Bath laboratory. The next session is preliminary testing and familiarisation (approx. 2-2.5 hours). The remaining 6 visits (4 exercise trials \& 2 baseline sample collection visits) will be split across 3 main blocks of the study, each lasting 28 days. Following preliminary testing, you will be randomised into supplementing with either BIMUNO®, or placebo. Block 1 will then begin with you attending the laboratory for a baseline sample collection visit, after which you will begin supplementation for the next 28 days. After this 28-day period, you will complete two exercise trials (details below). The ambient temperature in these trials (separated by \>3 days) will differ (20 \& 35˚C) and will occur in a random order. The second block (termed the 'washout' period) will be a 28-day period where you will take neither BIMUNO® nor the placebo. The third block will then commence and will be identical to block 1 - the only difference being you will take the alternative supplement.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

BASIC_SCIENCE

Masking

Eligibility

Sex: ALLMin age: 18 YearsMax age: 60 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * Regular exerciser - defined as participating in at least 30 mins of structured exercise at least 3 times per week * Able to complete two hours of moderate intensity cycling * Aged 18-60 years Exclusion Criteria: * Use of products marketed as prebiotics, probiotics or synbiotics within 4 weeks prior to study entry (e.g. Yakult, Actimel, Activia, VSL#3, Kefir). Regular cheese or yogurt containing lactic acid bacteria are not an exclusion criterion. * Systemic antibiotic or antimycotic treatment within 4 weeks prior to study entry. * Following diets likely to affect study outcomes: e.g. low FODMAP, KETO/high-fat, gluten free/coeliac, paleo, weight loss, caloric restriction, low-carb, 5:2/whole day energy restriction, Atkins/high-protein, sugar-free, single-food, juicing/any day of juicing, any other restriction diet (e.g. very low calory), or vegan diets (GOS is derived from cow's milk). * Changes in diet, supplement use or medication likely to affect study outcomes within 2 months prior to study entry or planned during the study.

Outcomes

Primary Outcomes

Exogenous carbohydrate oxidation rate

amount of ingested carbohydrate used for energy within the body. measures in grams per minute and is calculated from breath samples

Time frame: 120 minutes

Secondary Outcomes

Whole-body carbohydrate oxidation rate

measured from breath samples. unit is grams per minute

Time frame: 120 minutes

Whole-body fat oxidation rate

measured from breath samples. unit is grams per minute

Time frame: 120 minutes

Endogenous carbohydrate oxidation rate

measured from breath samples. unit is grams per minute

Time frame: 120 minutes

Blood lactate concentrations

measured from blood samples in millimoles per litre

Time frame: 120 minutes

Blood glucose concentrations

measured from blood samples in millimoles per litre

Time frame: 120 minutes

Plasma NEFA concentrations

measured from blood samples in micromoles per litre

Time frame: 120 minutes

Plasma insulin concentrations

measured from blood samples in picomoles per litre

Time frame: 120 minutes

Urinary calcium/creatinine ratio

measured from urine sample - ratio of milligrams per decilitre of calcium to milligrams per decilitre

Time frame: 28 days

Plasma 25-hydroxyvitamin D concentration

measured from blood samples. unit is nanomoles per litre

Time frame: 28 days

Plasma zinc concentration

measured from blood samples. unit is micrograms per decilitre

Time frame: 28 days

Plasma ferritin concentration

measured from blood samples. unit is micrograms per litre

Time frame: 28 days

Plasma vitamin B1 concentration

measured from blood samples. unit is micrograms per decilitre

Time frame: 28 days

Plasma vitamin B6 concentration

measured from blood samples. unit is micrograms per litre

Time frame: 28 days

Plasma vitamin C concentration

measured from blood samples. unit is micromoles per litre

Time frame: 28 days

Plasma vitamin E concentration

measured from blood samples. unit is micrograms per millilitre

Time frame: 28 days

Haemoglobin concentration

measured from blood samples. grams per decilitre

Time frame: 120 minutes

Haematocrit

measured from blood samples. unit is percentage of red blood cells in blood

Time frame: 120 minutes

Plasma intestinal fatty acid binding protein concentration

measured from blood samples. unit is nanograms per microlitre

Time frame: 120 minutes

Subjective scale: Gas