Summarized findings of studies (1970–2004) investigating the effects of yoga and yoga-based programs on insulin resistance, lipid profiles, and body size and composition, stratified by study design and intervention (yoga, including yoga-based meditation, alone vs. in combination with other interventions). Studies demonstrating beneficial effects are in bold type.
Findings, by Endpoint | Study Design | ||||||
---|---|---|---|---|---|---|---|
Cross-Sectional (Yoga Alone) | Uncontrolled Clinical Trials (>2 sessions) | Non-Randomized Controlled Clinical Trials (>2 Sessions) | Randomized Clinical Trials (>2 sessions) | ||||
Yoga Alone | Multiple Interventions | Yoga Alone | Multiple Interventions | Yoga Alone | Multiple Interventions | ||
Markers of insulin resistance | |||||||
Fasting glucose | |||||||
Reduced | [85, 86, 89, 90] | [68, 92] | [88, 93] | [80] | [95] | ||
No change | [94]* | [87] | |||||
Post prandial glucose | |||||||
Reduced | [85, 86, 89, 91] | [92] | |||||
No change | [87] | ||||||
Reduced fasting insulin | [87](NS) | ||||||
Reduced fasting glycated hemoglobin | [85, 86] | [95] | |||||
Lipid profiles | |||||||
Total Cholesterol | |||||||
Reduced | [96] | [94](NS) [89, 90, 97]† | [68] | [88] | [80, 98] | [78, 79, 99] | |
Increased | [100] | ||||||
Unchanged | [79]‡ [101] | ||||||
Triglycerides | |||||||
Reduced | [96] | [78, 99, 100] | |||||
Increased | [94] | ||||||
Increased high density lipoproteins | [68] | ||||||
Low density lipoprotein (LDL) | |||||||
Reduced | [80, 98] | [78, 99] | |||||
Increased | [100] | ||||||
Anthropometric markers | |||||||
Reduced BMI | [92] | [98] | [100] | ||||
Reduced | [89, 91, 103] | [104] | [93] | [80] | [106, 107] | [78, 99] | |
Unchanged | [97]† [108] | [109] | [101] | ||||
Body composition | |||||||
Reduced waist, hip circumference | [106] | ||||||
Reduced skin fold thickness‡ | [106] | ||||||
↓ % body fat, ↑ % lean mass | [105] | ||||||
No change (% body fat, fat mass) | [108] |
* Sexes analyzed separately; trend toward reduced fasting glucose in men (N = 53, 0.5 < P < .1), despite low baseline fasting glucose levels (x = 64.4 ± 6.2).
† With biofeedback.
‡ In individuals at risk for CVD, cholesterol was lower at 0 and 8 months post-intervention, but not at 4 year follow-up
§Triceps, subscapular, thigh, calf, etc, skin folds.106