Open Access Highly Accessed Research article

A double-blind, randomized clinical trial of dietary supplementation on cognitive and immune functioning in healthy older adults

John E Lewis1*, Angelica B Melillo1, Eduard Tiozzo1, Lawrence Chen1, Susanna Leonard1, Mark Howell2, Janelle Diaz2, Kathy Gonzalez3, Judi M Woolger3, Janet Konefal1, Elaine Paterson4 and David Barnes4

Author Affiliations

1 Department of Psychiatry & Behavioral Sciences, University of Miami Miller School of Medicine, 1120 NW 14th Street, Miami, FL 33136, USA

2 Medical Wellness Center, University of Miami Miller School of Medicine, 1120 NW 14th Street, Miami, FL 33136, USA

3 Department of Medicine, University of Miami Miller School of Medicine, 1120 NW 14th Street, Miami, FL 33136, USA

4 Standard Process, 1200 W. Royal Lee Drive, Palmyra, WI 53156, USA

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BMC Complementary and Alternative Medicine 2014, 14:43  doi:10.1186/1472-6882-14-43

Published: 4 February 2014

Abstract

Background

Declining cognitive function is relatively common and increasingly prevalent. Studies have shown that different nutrients (e.g., Ginkgo biloba and vitamin E) appear to be effective at improving memory and concentration, while less is known about their effect on immunity.

Methods

This study investigated the effect of Ginkgo Synergy® plus Choline (n = 33) and OPC Synergy® plus Catalyn® (n = 31) versus placebo (n = 33) in a 6-month, randomized, double-blind trial on cognitive and immune functioning among English-speaking, non-smoking, healthy older adults. The Stroop Color and Word Test, Trail Making Test A and B, Controlled Oral Word Association, Hopkins Verbal Learning, Mini-Mental State Exam, and Digit Symbol were administered at baseline and 3 and 6 months follow-up to assess cognitive functioning. Cytokines and growth factors were measured at baseline and 6 months to assess inflammation and immune functioning. Data were analyzed with linear mixed modeling.

Results

No serious adverse events were noted in this study. According to time on the Trail Making Test-B, the Ginkgo Synergy® plus Choline arm showed improvement from baseline to 3 months follow-up (mean difference = 24.2; SE = 6.4; 95% CI: 8.6, 39.7; p = 0.01). On the Controlled Oral Word Association Trial-S, the scores significantly increased for the Ginkgo Synergy® plus Choline arm from baseline to 6 months follow-up (mean difference = 2.1; SE = 0.8; 95% CI: 0.2, 3.9; p < 0.05) and for the OPC Synergy® plus Catalyn® arm from baseline to 3 months follow-up (mean difference = 2.1; SE = 0.8; 95% CI: 0.2, 4.0; p < 0.05). Epidermal growth factor significantly decreased from baseline to 6 months follow-up for the Ginkgo Synergy® plus Choline arm (mean difference = 120.7; SE = 28.4; 95% CI: 62.6, 178.8; p < 0.001).

Conclusions

Our study showed isolated and modest effects of a Ginkgo biloba plus choline-based formula on cognitive and immune functioning among healthy older adults with no history of significant cognitive deficits. Our trial was registered with clinicaltrials.gov (ID: NCT01672359). This study was supported by a grant from Standard Process, Inc.

Keywords:
Cognitive functioning; Immune functioning; Ginkgo biloba; Choline; Dietary supplement; Older adults; Trail making test; Controlled oral word association; Epidermal growth factor