The study involves the intake of Low-methoxy (LM) pectin (polysaccharides extracted from citrus peels), which are commonly found in the UK diet (not pharmacological agents), to test their effects on systematic inflammation in the body and gut microbiome composition. Study subjects will be healthy elderly with early signs of frailty or pre-frailty from the local population and will be asked to attend the laboratory on 2 occasions; before and after 4-week' supplementing the diet daily with either 10g of pectin with 10g of whey protein and 10g of cocoa powder added as flavour (active arm) or 10g of whey protein with 10g of cocoa powder added as flavour (placebo). Participants will be given the blinded products portioned in individual sachets, with instructions to add the contents of one sachet a day to 150ml of milk and to consume immediately.

At each study visit (~90 minutes), participants will be asked to provide a stool and blood sample, will have blood pressure, heart rate, weight, height, and waist/hip ratio measured, research team will perform physical functioning test (Time up and go test, 30-second sit to stand test) as well as participants will complete the quality-of-life questionnaire (SF-36), the Depression and Anxiety (HADS) and the Gastrointestinal Symptom Rating Scale (GSRS).

The overall aim of the proposed project is to study the effect of daily ingestion of a dietary fibre (LM pectin) among frail population on anti-inflammatory and cardioprotective metabolic measures and to determine whether effects are mediated via the modulation of the gut microbiome and SCFAs production.

Specific Aim 1: To determine the effects of 4-weeks' pectin dietary supplementation on gut microbiome composition and diversity and the concentration of markers of intestinal permeability in the blood.

Specific Aim 2: To investigate the impact of daily pectin intake on physical functioning and subjective quality of life.

Specific Aim 3: To investigate the consequences of 4-weeks' daily ingestion of pectin on subjective measures of depression and anxiety among frail participants.

30 healthy elderly with early signs of frailty or pre-frailty will be recruited following a successful medical screening.

Inclusion Criteria:

• Participant is willing and able to give informed consent for participation in the study.
• Participant eligibility includes those aged >65 years who have a body mass index (BMI) between 18.5 and 39.9 kg/m2.
• Participants who are considered as pre-frail or frail based on FRAIL (Simple Frailty Questionnaire).

Exclusion Criteria:

• Have gastrointestinal conditions e.g. malabsorptive conditions such as IBS/IBD, coeliac or functional conditions such as gastroparesis or food intolerances etc.
• History of major surgery which potentially limit participation or completion of the study.
• History of gastrointestinal resection surgery, including bariatric surgery.
• Used of antibiotics, antifungal medications, probiotics or prebiotics 90 days before the start of the study.
• Are taking the following medications: immunosuppressants, amiodarone and/or perhexiline.
• Are currently following or anticipated to commence a specialised commercially available weight loss diet and/or program.
• History of side effects towards probiotics or prebiotics.
• History or current psychiatric illness.
• History or current neurological condition (e.g. epilepsy).
• Having taken part in a research study in the last 3 months involving invasive procedures or an inconvenience allowance.

The research team will try their best to share statistical plan with other researchers

Double-blinded.