Effects of In-between Meal Products on Cognitive Function in the Elderly

Functional brain activity will be measured by functional magnetic resonance imaging (fMRI)) during the n-back task

Fasting blood glucose insulin will be taken and the HOMA index (Homeostatic Model Assessment for Insulin Resistance) expressed in mmol/L or mg/dL will be used to assess insulin resistance

Blood fats/lipid status unit of measurement concentration given mmol/L

Concentration of interleukin-6 measured in in blood serum corrected for baseline, unit of measurement concentration given as pg/mL

High-sensitivity C-reactive protein (HsCRP) measured in blood corrected for baseline, unit of measurement concentration given as mg/L

Concentration of Tumor necrosis factor (TNF) in blood serum corrected for baseline, unit of measurement concentration given as pg/mL

Concentration of Interferon-gamma (IFN-Gamma) in blood serum corrected for baseline, unit of measurement concentration given as pg/mL

Zonulin (haptoglobin 2 precursor) is a protein that increases the permeability of tight junctions between cells of the wall of the digestive tract, measured in faeces.

Intestinal fatty-acid binding protein (I-FABP) measured in faeces

Cognitive function will be assessed by an off-line multi-domain cognitive test battery computer-based, word recognition task

Resting state connectivity functional MRI (rsfMRI) and brain morphology from structural scans (brain and brain stem) are measured by MRI

The Perceived Stress Scale (PSS) questionnaire is used to measure the perception of stress in life and has 10 questions with the following options to answer: 0 = Never 1 = Almost Never 2 = Sometimes 3 = Fairly Often 4 = Very Often

The validated Hospital Anxiety and Depression Scale (HADS) questionnaire will be used to assesses symptoms of depression and anxiety. The HADS has 7 questions related to depressions and 7 questions related to anxiety. A higher total score indicates more depression or anxiety with the following cut off scores: 0-7 = Normal 8-10 = Borderline abnormal (borderline case) 11-21 = Abnormal (case)

The SF 36 (short form) questionnaire is used to assess general health Status. The SF-36 consists of 36 questions. Scores for the different domains are converted and pooled using a scoring key, for a total score indicating a range of low to high quality of life

To evaluate hip and knee osteoarthritis Western Ontario and McMaster Osteoarthritis Index (WOMAC) questionnaire is used. The WOMAC is a self-administered questionnaire consisting of 24 items divided into 3 subscales. The test questions are scored on a scale of 0-4, which correspond to: None (0), Mild (1), Moderate (2), Severe (3), and Extreme (4). The scores for each subscale are summed up, with a possible score range of 0-20 for Pain, 0-8 for Stiffness, and 0-68 for Physical Function. A sum of the scores for all three subscales gives a total score

The translated and validated Swedish version of the Clinical Outcomes in Routine Evaluation (CORE-GP) is used to evaluate psychological wellbeing. The CORE-GP consists of 34 questions about how they have been feeling over the last week, using a 5-point scale (not at all, only occasionally, sometimes, often, most or all the time. The scale covers four dimensions: subjective well-being, problems/symptoms, life functioning, risk/harm

To assess gastrointestinal symptoms the Gastrointestinal Symptoms Rating Scale (GSRS) questionnaire is used. The questionnaire consists of 15 questions combined into five symptom clusters: reflux, abdominal pain, indigestion, diarrhoea and constipation. Each questions is rated on a 7-point likert scale where 1 represents absence of troublesome symptoms and 7 represents very troublesome symptoms

To assess sleep quality and sleep disturbances over a one-month time interval the Pittsburgh Sleep Quality Index (PSQI) questionnaire is used. Each questionnaire's 19 self reported items belong to one of seven categories: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, daytime dysfunction. The questionnaire consists of a combination of likert-type and open-ended questions. Scores for each question range from 0 to 3, with higher scores indicating more acute sleep disturbances.

The International Physical Activity Questionnaire for the Elderly (IPAQ-E) short form consists of 4 questions regarding time spend sitting, walking, heavy physical activities or sport or very heavy activities or sport

The Historical Physical Activity Questionnaire HAPAQ assesses physical activity behaviour between the age of 20 to 65 years and consists of questions regarding physical activity, sports and labour performed per year, month and average minutes per week

The Meal-Q Food frequency questionnaire is used to assess if participants have altered dietary patterns during the intervention. The questionnaire consists of 174 questions about foods, dishes and drinks (including alcoholic drinks) as well as pictures of different portion sizes for cooked dishes, questions about meal order, eating behaviour (with regard to restaurant visits, fast food, salad buffets, salt on food, consumption of diet products) and supplements.

Habitual physical activity will be assessed by accelerometery activity monitor during a week during waking time. Counts per minute are registered and converted into daily average times spent in sedentary behaviour, light-intensity physical activity, and moderate-to-vigorous intensity physical activity.

Muscle mass is assessed with bioelectrical impedance (BIA)

Fat mass is assessed with bioelectrical impedance (BIA)

Body mass index (BMI) is calculated as weight (in kg)/ height^2 (in m^2)

Waist circumference is measured to the nearest 0.1 cm with a steel tape at the midpoint between iliac crest and lower costal marginBody mass index (BMI)

Aerobic capacity is assessed by a maximal walk test on a graded treadmill (Modified Bruce Protocol) where a further stage and time into the stage indicates a better aerobic fitness

Balance by the single leg stance balance test with eyes open and eyes closed where longer time indicates a better balance

Lower body muscle performance is assessed by the 30-sec repeated chair raise where more repetitions indicates a better performance

Maximal leg strength is assessed by the leg press exercise where a larger amount in kilograms lifted indicates a higher maximal leg strength

Maximal handgrip strength by the handgrip test where total amount of kilogram or kilogram per bodyweight indicates a higher total, or relative handgrip strength respectively