Is there a single major study involving a randomized controlled trial that strongly suggests that long term meditation indubitably aids in a certain function of

Is there a single major study involving a randomized controlled trial that strongly suggests that long term meditation indubitably aids in a certain function of humans? For the sake of clarity, a major study is designed like this: Low-fat dietary pattern and risk of colorectal cancer: the Women's Health Initiative Randomized Controlled Dietary Modification Trial. DESIGN, SETTING, AND PARTICIPANTS: The Women's Health Initiative Dietary Modification Trial, a randomized controlled trial conducted in 48,835 postmenopausal women aged 50 to 79 years recruited between 1993 and 1998 from 40 clinical centers throughout the United States. Source: http://www.ncbi.nlm.nih.gov/pubmed/16467233 http://www.ncbi.nlm.nih.gov/pubmed/16467233