Obesity
Conditions
Brief summary
Conjugated linoleic acid (CLA) is form of fat found in dairy foods, beef and other natural sources. When given to small animals, decreases of body fat have been noted.. Although weight loss is the best treatment for overweight and obesity, it is difficult to maintain the loss in the long term. Because of this, treatment emphasis has turned to small weight losses obtained through non-restrictive diets and prevention of weight regain. This is a study to determine if 6 months of consumption a purified form of CLA will result in greater loss of body fat than control and to determine whether CLA consumption increases total fat oxidation, which would help explain why the weight loss occurs.
Detailed description
Subjects were screened and then underwent baseline evaluation. The substudy evaluation measured 24-h energy expenditure and substrate utilization by using a whole-room indirect calorimeter. Dietary fat oxidation was measured by mixing \[1-13C\]oleate and D31-palmitate into a breakfast meal and then collecting breath carbon dioxide and urine to measure the end products of oxidation. Subjects were then provided either 4 g/d of 78% active CLA isomers (3.2 g/d: 39.2% cis-9,trans-11 and 38.5% trans-10,cis-12) or 4 g/d of safflower oil placebo as 1-g gel capsule supplements. The baseline evaluations were repeated 6 mo later.
Interventions
4 grams per day of 39% cis-9, trans-11 CLA; 39% trans-10, cis-12 CLA, and 22% safflower oil for 6 months
Sponsors
University of Wisconsin, Madison
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 44 Years
Healthy volunteers
No
Inclusion criteria
* BMI 25-29.9 kg/m2 * Absence of a weight change of greater than 3 kg in the previous 6 months
Exclusion criteria
* Presence of a physical limitation to walking exercise * Current or recent (6 months) enrollment in a commercial or self-prescribed weight loss program * A history of metabolic disease-ie. renal, endocrine, hepatic or gastrointestinal disease that would impact the outcome of the study * A history of a psychiatric or eating disorders Ÿ Presence of metal implants that would interfere with body composition analysis * Fasting plasma cholesterol \>300mg/dl or triglycerides above 500 mg/dl. * Abnormal EKG
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Fat Mass | 6 months | loss of fat mass, kg |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Total Fat Oxidation | 6 months | 24 hour respiratory gas analysis |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Conjugated Linoleic Acid 3 grams per day for 7 months | 24 |
| Placebo 3 grams per day of sunflower oil for 7 months | 24 |
| Total | 48 |
Baseline characteristics
| Characteristic | Placebo | Conjugated Linoleic Acid | Total |
|---|---|---|---|
| Age, Categorical <=18 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical >=65 years | 0 Participants | 0 Participants | 0 Participants |
| Age, Categorical Between 18 and 65 years | 24 Participants | 24 Participants | 48 Participants |
| Age, Continuous | 32 years STANDARD_DEVIATION 7 | 34 years STANDARD_DEVIATION 8 | 33 years STANDARD_DEVIATION 9 |
| Region of Enrollment United States | 24 participants | 24 participants | 48 participants |
| Sex: Female, Male Female | 20 Participants | 18 Participants | 38 Participants |
| Sex: Female, Male Male | 4 Participants | 6 Participants | 10 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 2 / 24 | 1 / 24 |
| serious Total, serious adverse events | 0 / 24 | 0 / 24 |
Outcome results
Primary
Fat Mass
loss of fat mass, kg
Time frame: 6 months
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Conjugated Linoleic Acid | Fat Mass | -1.0 kg | Standard Deviation 2.2 |
| Placebo | Fat Mass | 0.7 kg | Standard Deviation 3 |
Comparison: Analysis of variance to test CLA not equal to placebop-value: <0.05ANOVA
Comparison: Pre- post treatment comparison o fat oxidation found that fat oxidation increased in CLA (4 +/- 8 g) and decreased in placebo (-7 +/- 11 g) groups during sleep. after 6 mo of supplementation.p-value: <0.05ANOVA
Secondary
Total Fat Oxidation
24 hour respiratory gas analysis
Time frame: 6 months