The Effects of a High Protein Diet on Microbiota, Gastrointestinal Function and Wellness in Older Women
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ClinicalTrials.gov Identifier: NCT02445560 |
Recruitment Status :
Completed
First Posted : May 15, 2015
Last Update Posted : March 29, 2018
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Condition or disease | Intervention/treatment | Phase |
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Aging | Dietary Supplement: Probiotic capsule and Fiber Sachet Dietary Supplement: Probiotic capsule and Placebo sachet Dietary Supplement: Placebo capsule and Fiber Sachet Dietary Supplement: Placebo capsule and Placebo sachet | Not Applicable |
Older women will be randomized to a 18-week crossover study design. During each treatment period participants will be provided with a weight maintenance diet providing approximately 2 g/kg/day of protein.
Following a two-week baseline and in random order will have the following diets assigned:
The participants will be provided with a weight maintenance, high protein diet for two weeks, then for two-weeks will resume their normal diet;
The participants will come back into clinic and for the next two weeks to receive a high protein diet with a multi-strain probiotic for two weeks, then for two-weeks will resume their normal diet;
The participants will come back into clinic and for the next two weeks will receive a high protein diet with a prebiotic, then for two-weeks will resume their normal diet;
The participants will come back into clinic and for the next two weeks will receive a high protein diet with the synbiotic combination. then for two-weeks will resume their normal diet
Participants and researchers will be blinded for each treatment period (participants will receive a probiotic or placebo capsule, and a prebiotic or placebo sachet).
The following will be performed during the clinic visits: Questionnaires will assess quality of life (QoL), wellness, gastrointestinal symptoms, bowel movement frequency, and compliance. Hand-grip strength will be measured. Blood and urine samples will be collected at baseline and at weeks 2, 6,10 and 14. Stool samples will be collected at baseline and at weeks 2, 4, 6, 8,10, 12, 14 and 16.
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 29 participants |
Allocation: | Randomized |
Intervention Model: | Crossover Assignment |
Masking: | Triple (Participant, Investigator, Outcomes Assessor) |
Primary Purpose: | Basic Science |
Official Title: | The Effects of a High Protein Diet on Microbiota, Gastrointestinal Function, Wellness and the Potential Mitigating Effects of a Multi-strain Probiotic, Prebiotic, and Synbiotic: a Randomized, Double-blinded Crossover Study in Older Women. |
Study Start Date : | June 2015 |
Actual Primary Completion Date : | October 2015 |
Actual Study Completion Date : | October 2015 |
Arm | Intervention/treatment |
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Experimental: Probiotic capsule and Fiber sachet
Participants will be randomly assigned to receive all of the following in random order: a probiotic capsule and fiber sachet daily for 2-weeks, a probiotic capsule and placebo sachet for 2-weeks, a fiber sachet and placebo capsule for 2-weeks, and placebo capsule and placebo sachet for 2-weeks. Each treatment period is separated by a 2-week washout. During each treatment period, in addition to consuming a probiotic capsule or placebo and/or a fiber sachet or placebo sachet participants will be on a controlled higher protein diet.
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Dietary Supplement: Probiotic capsule and Placebo sachet
A probiotic capsule and placebo sachet will be consumed daily for 2-weeks. The probiotic capsule contains a mixture of Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus and Lactobacillus plantarum. The placebo sachet consists of 5 g of maltodextrin. During the treatment period, in addition to consuming the probiotic capsule and placebo sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Placebo capsule and Fiber Sachet A placebo capsule and fiber sachet will be consumed daily for 2-weeks. The placebo capsule will contain potato starch, magnesium stearate and ascorbic acid. The fiber sachet consists of 5 g of chicory root fiber. During the treatment period, in addition to consuming the placebo capsule and fiber sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Placebo capsule and Placebo sachet A placebo capsule and placebo sachet will be consumed daily for 2-weeks. The placebo capsule will contain potato starch, magnesium stearate and ascorbic acid. The fiber sachet consists of 5 g of maltodextrin. During the treatment period, in addition to consuming the placebo capsule and placebo sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. |
Experimental: Probiotic capsule and Placebo sachet
Participants will be randomly assigned to receive all of the following in random order: a probiotic capsule and fiber sachet daily for 2-weeks, a probiotic capsule and placebo sachet for 2-weeks, a fiber sachet and placebo capsule for 2-weeks, and placebo capsule and placebo sachet for 2-weeks. Each treatment period is separated by a 2-week washout. During each treatment period, in addition to consuming a probiotic capsule or placebo and/or a fiber sachet or placebo sachet participants will be on a controlled higher protein diet.
|
Dietary Supplement: Probiotic capsule and Fiber Sachet
A probiotic capsule and fiber sachet will be consumed daily for 2-weeks. The probiotic capsule contains a mixture of Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus and Lactobacillus plantarum. The fiber sachet consists of 5 g of chicory root fiber. During the treatment period, in addition to consuming the probiotic capsule and fiber sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Placebo capsule and Fiber Sachet A placebo capsule and fiber sachet will be consumed daily for 2-weeks. The placebo capsule will contain potato starch, magnesium stearate and ascorbic acid. The fiber sachet consists of 5 g of chicory root fiber. During the treatment period, in addition to consuming the placebo capsule and fiber sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Placebo capsule and Placebo sachet A placebo capsule and placebo sachet will be consumed daily for 2-weeks. The placebo capsule will contain potato starch, magnesium stearate and ascorbic acid. The fiber sachet consists of 5 g of maltodextrin. During the treatment period, in addition to consuming the placebo capsule and placebo sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. |
Experimental: Placebo capsule and Fiber sachet
Participants will be randomly assigned to receive all of the following in random order: a probiotic capsule and fiber sachet daily for 2-weeks, a probiotic capsule and placebo sachet for 2-weeks, a fiber sachet and placebo capsule for 2-weeks, and placebo capsule and placebo sachet for 2-weeks. Each treatment period is separated by a 2-week washout. During each treatment period, in addition to consuming a probiotic capsule or placebo and/or a fiber sachet or placebo sachet participants will be on a controlled higher protein diet.
|
Dietary Supplement: Probiotic capsule and Fiber Sachet
A probiotic capsule and fiber sachet will be consumed daily for 2-weeks. The probiotic capsule contains a mixture of Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus and Lactobacillus plantarum. The fiber sachet consists of 5 g of chicory root fiber. During the treatment period, in addition to consuming the probiotic capsule and fiber sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Probiotic capsule and Placebo sachet A probiotic capsule and placebo sachet will be consumed daily for 2-weeks. The probiotic capsule contains a mixture of Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus and Lactobacillus plantarum. The placebo sachet consists of 5 g of maltodextrin. During the treatment period, in addition to consuming the probiotic capsule and placebo sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Placebo capsule and Placebo sachet A placebo capsule and placebo sachet will be consumed daily for 2-weeks. The placebo capsule will contain potato starch, magnesium stearate and ascorbic acid. The fiber sachet consists of 5 g of maltodextrin. During the treatment period, in addition to consuming the placebo capsule and placebo sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. |
Placebo Comparator: Placebo capsule and Placebo sachet
Participants will be randomly assigned to receive all of the following in random order: a probiotic capsule and fiber sachet daily for 2-weeks, a probiotic capsule and placebo sachet for 2-weeks, a fiber sachet and placebo capsule for 2-weeks, and placebo capsule and placebo sachet for 2-weeks. Each treatment period is separated by a 2-week washout. During each treatment period, in addition to consuming a probiotic capsule or placebo and/or a fiber sachet or placebo sachet participants will be on a controlled higher protein diet.
|
Dietary Supplement: Probiotic capsule and Fiber Sachet
A probiotic capsule and fiber sachet will be consumed daily for 2-weeks. The probiotic capsule contains a mixture of Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus and Lactobacillus plantarum. The fiber sachet consists of 5 g of chicory root fiber. During the treatment period, in addition to consuming the probiotic capsule and fiber sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Probiotic capsule and Placebo sachet A probiotic capsule and placebo sachet will be consumed daily for 2-weeks. The probiotic capsule contains a mixture of Bifidobacterium bifidum, Bifidobacterium breve, Bifidobacterium longum, Lactobacillus acidophilus and Lactobacillus plantarum. The placebo sachet consists of 5 g of maltodextrin. During the treatment period, in addition to consuming the probiotic capsule and placebo sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. Dietary Supplement: Placebo capsule and Fiber Sachet A placebo capsule and fiber sachet will be consumed daily for 2-weeks. The placebo capsule will contain potato starch, magnesium stearate and ascorbic acid. The fiber sachet consists of 5 g of chicory root fiber. During the treatment period, in addition to consuming the placebo capsule and fiber sachet participants will consume a controlled diet consisting of foods that provide an average of approximately 2 g/kg/day of protein. |
- Microbiota Studies (recovery) [ Time Frame: Change from Baseline at Week 2,4,6,8,10,12,14,16 ]Change in the concentrations of the probiotic strains in the stools will be measured with strain specific deoxyribonucleic acid (DNA) (or antibodies) in fecal samples (e.g. quantitative polymerase chain reaction (qPCR), flow cytometry).
- Microbiota Studies (overall composition) [ Time Frame: Change from Baseline at Week 2,4,6,8,10,12,14,16 ]Effects of the probiotic interventions on overall microbiota composition (e.g. 454 16S rRNA (ribosomal ribonucleic acid) sequencing) will also be measured.
- Digestive Health (Gastrointestinal Symptom Rating Scale ) [ Time Frame: Change from Baseline at Week 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18 ]Measured by gastrointestinal symptoms (gas, bloating, diarrhea, etc.) assessed using the weekly Gastrointestinal Symptom Rating Scale (GSRS).
- Digestive Health (Bristol Stool Scale) [ Time Frame: Change from Baseline at Week 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18 ]Measured by gastrointestinal symptoms (gas, bloating, diarrhea, etc.) assessed using a daily questionnaire. The daily questionnaire will include questions regarding symptoms and the Bristol Stool Scale (stool form and transit).
- Blood Analysis (metabolic) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by comprehensive Metabolic Panel
- Blood Analysis (lipids) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by Lipid Panel
- Blood Analysis (inflammation) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by Inflammatory markers
- Blood Analysis (blood count) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by Complete Blood Count (CBC)
- Blood Analysis (signalling) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by (mammalian target of rapamycin) mTOR
- Blood Analysis (regulation) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by insulin-like growth factor 1 (IGF-1)
- Blood Analysis (proteolysis) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by total p-cresol
- General Wellness [ Time Frame: Day 1 through 126 ]Individual reporting of antibiotic usage, visits to a physician, etc.
- Proteolytic Activity [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Measured by urinary p-cresol, indoxyl sulfate and urine urea nitrogen (UUN)
- Measures of Quality of Life (QoL) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]QoL questionnaire (domains such as physical functioning, general health, bodily pain, vitality, social functioning), questionnaire to assess frailty, and hand grip strength
- Measures of Well-being (frailty) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Questionnaire to assess frailty
- Measures of Well-being (hand grip) [ Time Frame: Change from Baseline at Weeks 2,6,10,14 ]Hand grip strength will be measured
- Acceptability of the Diet [ Time Frame: Day 1 through 126 ]Acceptability will be measured using the daily questionnaire and participant compliance recordings/logs of any unconsumed foods during treatment periods

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 65 Years and older (Older Adult) |
Sexes Eligible for Study: | Female |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
To participate in the study you must
- be a woman 65 years of age or older
- be willing to complete daily and weekly questionnaires
- be willing to wear a SenseWear Pro Armband (BodyMedia, Inc.) to monitor energy expenditure and establish dietary energy needs
- be willing to provide blood samples, stool samples, and urine samples throughout the course of the study
- be willing to discontinue prebiotics, probiotics and/or any fiber supplements for the duration of the study
- be willing to consume the provided diet for the designated 8 weeks of the study
- are willing to report and maintain their usual alcohol intake throughout the study
- are able to take foods, study fiber, probiotic, and placebo without the aid of another person
- able to attend all scheduled study appointments for the duration of the study
- have a usual protein intake consistent with United States' population as assessed by dietary analysis
- have a usual fiber intake consistent with United States' population as assessed by dietary analysis
- be willing to provide a social security number to receive study payment.
Exclusion Criteria:
To participate in the study you must NOT
- have a physician-diagnosed gastrointestinal disease or condition (such as ulcerative colitis, Crohn's disease, gastroparesis, peptic ulcer disease, cancer, celiac disease, short bowel disease, ileostomy)
- have had or are currently being treated for any known illnesses or conditions that may impact perceived health such as HIV/AIDS, immune modulating diseases (autoimmune, hepatitis, cancer, etc.), diabetes or chronic kidney disease
- be a vegetarian
- have any known food allergies or dietary restrictions
- be currently taking medication for constipation or diarrhea
- have taken antibiotics within the past 2 months
- be a current smoker
- be planning on loosing/gaining weight during the next 6 months
- typically consume no more than one alcoholic beverage per day
- have a BMI greater than 30

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02445560
United States, Florida | |
UF Food Science and Human Nutrition Department | |
Gainesville, Florida, United States, 32611 | |
UF/IFAS Extension Office Marion County | |
Ocala, Florida, United States, 34470 |
Principal Investigator: | Wendy Dahl, PhD, RD | University of Florida |
Responsible Party: | University of Florida |
ClinicalTrials.gov Identifier: | NCT02445560 |
Other Study ID Numbers: |
IRB201400955 |
First Posted: | May 15, 2015 Key Record Dates |
Last Update Posted: | March 29, 2018 |
Last Verified: | March 2018 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | Undecided |
probiotics prebiotics high protein diet microbiota |