The Influence of Probiotics on Body Weight and Composition (WLP)

The Influence of Probiotics With a Behavioral Life Style Intervention on Body Weight and Composition in Overweight Participants: A Randomized, Double-blinded, Placebo-controlled Study.

The purpose of this study is to evaluate the addition of two different probiotic interventions to a comprehensive behavioral lifestyle intervention on body weight loss and overall health in overweight adults.

This is a randomized, double-blinded, placebo-controlled study. After obtaining informed consent, healthy overweight adults aged 18 to 75 years (n=76/intervention group with n=228 total/study) will be randomized to one of three groups: Lactobacillus, a blend of Bifidobacterium and Lactobacillus, or placebo. Participants will consume 1 capsule per day of probiotic or placebo for 12 weeks. Participants will attend weekly behavioral lifestyle intervention meetings, which will address dietary and physical activity contributions to weight loss, in groups of approximately 20 subjects during the 12 intervention weeks. Participants will complete daily questionnaires throughout the week before and during the intervention period which address subject compliance and bowel habits. A dual X-ray absorptivity scan will be done to measure body composition during the week before the intervention and during the 12th week of the intervention period (± 1 week). Blood samples will be collected via a finger prick at the baseline and final time points. Blood samples will be used to measure cardiovascular and metabolic markers of health. Stool samples will be collected from 25 subjects per intervention group during the week before the intervention period and the 12th week of the intervention period. Dietary intake will be assessed during the week before the intervention period and during the week of the final appointment (± 1 week). Gastrointestinal symptoms and physical activity questionnaires will be completed upon providing consent to the study, being randomized to an intervention, and during the last week of the intervention period. Questionnaires regarding income, weight control strategies, and quality of life will be completed during randomization and during the last week of the intervention period. Stool samples will be collected from a subgroup of participants during the week before the intervention period and during the 12th week of the intervention period. These samples will be used to detect the presence and/or abundance and/or survival of the probiotic microorganisms at the end of the digestive tract.

This arm will be used as a control to asses the efficacy of the other probiotic arms. The placebo will contain encapsulated potato starch and magnesium stearate which is used the matrix in the probiotic supplements. The placebo refers only to the intervention supplement, not the behavioral lifestyle intervention. All subjects will participate in the same behavioral lifestyle intervention. In addition, blood tests will be performed.

Lactobacillus will be taken as a capsule once daily for 12 weeks by subjects in the group receiving this supplement (group is unknown, double-blinded). All subjects will participate in the same behavioral lifestyle intervention. In addition, blood tests will be performed.

A blend of Bifidobacterium and Lactobacillus will be taken as a capsule once daily for 12 weeks by subjects in the group receiving this supplement (group is unknown, double-blinded). All subjects will participate in the same behavioral lifestyle intervention. In addition, blood tests will be performed.

This group will receive the Lactobacillus probiotic, which will be taken as a capsule once daily for 12 weeks.

All participants will participate in weekly group meetings of 15 to 20 participants for a facilitated discussion of specific nutritional, behavioral, and physical activity topics chosen to promote weight loss.

This group will receive the placebo and will be taken as a capsule once daily for 12 weeks. The placebo will contain encapsulated potato starch which is used the matrix in the probiotic supplements.

This group will receive the blend of Bifidobacterium and Lactobacillus probiotic, which will be taken as a capsule once daily for 12 weeks.

Changes in baseline to week 12 in the percentage of body weight lost between the probiotic groups and the placebo group

Changes in body composition (Sagittal abdominal diameter) between the probiotic groups and the placebo group

Symptoms measured using the Gastrointestinal Symptom Rating Score questionnaire provide a score for the follow five syndromes: abdominal pain, reflux, constipation, diarrhea, and indigestion.

Total energy intake (kcal) will be assessed using the automated self-administered 24 hour dietary recall.

Changes in intestinal microbiota community composition between the probiotic groups and the placebo group

Stool samples will be collected from a subgroup of participants to analyze intestinal microbiota community composition.

Inclusion Criteria: To participate in the study you must: Be age 18 to 75 years Have a BMI ≥ 25 Be willing to receive random assignment to probiotic or placebo supplementation Be willing to and able to complete the Informed Consent Form in English Be willing to complete questionnaires, records, and diaries associated with the study and to complete all study visits Be committed to losing weight over the 12-week study period Be willing to discontinue consumption of fermented foods or probiotics (e.g., yogurts with live, active cultures or supplements). Be willing to provide a social security number (SS#) to receive study payment? Note: the subject can still participate if unwilling to provide SS#, but no financial reimbursement can be provided. Exclusion Criteria: To participate in the study you must NOT: Have used another investigational product within 3 months of enrolling in the study Be pregnant or breast-feeding or planning on becoming pregnant in the next 18 months Be allergic to milk, soy, or yeast Have gained or lost at least 10 lbs in the previous 3 months Have had uncontrolled angina (severe chest pain) within the past 6 months Have insulin-dependent diabetes (oral medications are not exclusionary) Use weight-loss medications Have had cancer treatment (radiation, chemotherapy, or surgery) within the past 6 months or any other treatment or condition known to weaken the immune system (e.g., systemic corticosteroids or HIV/AIDS) Be currently being treated for or have any of the following physician-diagnosed diseases or conditions: inflammatory bowel disease, celiac disease, short bowel syndrome, or any other malabsorptive syndrome? Have any physical condition deemed likely to significantly interfere with your ability to participate in a lifestyle intervention involving eating and physical activity changes Be currently participating in Weight Watcher's or another weight loss program