“This study is the first to obtain evidence using a randomized controlled trial to demonstrate curcumin’s efficacy in treating common cold symptoms in healthy humans,” they wrote in the Journal of Dietary Supplements.
The study was led and funded by Japanese botanical ingredient supplier Theravalues Corporation to evaluate the effects of its Theracurmin ingredient. Developed as a highly bioavailable form of curcumin, the ingredient’s anti-inflammatory effects on cognitive, cardiovascular, joint, and liver health have already been studied in over 30 clinical trials.
Curcumin for the common cold
Noting the current lack of preventive and therapeutic options for many viral infections, the researchers sought to evaluate the effects of both a standard and super dose of Theracurmin on common cold symptoms, immune function, and inflammatory markers.
They cited research supporting the anti-inflammatory and immunomodulatory effects of polyphenols, such as curcumin, in helping to fight off the common cold.
“Some previous studies showed that curcumin inhibited the production of bradykinin and prostaglandins through its anti-inflammatory effects,” the researchers added. “Furthermore, other studies reported that curcumin suppressed the release of inflammatory cytokines, such as tumor necrosis factor (TNF)-α and interleukin (IL)-1β, IL-6, and IL-8, and exhibited antiviral properties.”
Therefore, the study hypothesized that curcumin with enhanced bioavailability may be effective in preventing local and systemic symptoms caused by viral upper respiratory tract infections.
The randomized, double-blind, placebo-controlled study recruited 99 healthy Japanese adults and randomly assigned them to one of the following three groups: TS-P1 (Theracurmin Super), CR-033P (Theracurmin), or placebo (n = 33 per group). During the 12-week intervention, each group consumed two capsules twice daily, equaling 150 mg/day.
The primary outcome was the cumulative number of days for which common cold symptoms persisted, with immunity, inflammatory, liver function, and physical examination measures as secondary outcomes. A safety assessment was also performed.
“Our data revealed that consumption of 150 mg/day curcumin equivalent of TS-P1 (Theracurmin Super) or CR-033P (Theracurmin), reduces common cold symptoms,” the researchers concluded. “In particular, consumption of 150 mg/day curcumin equivalent of TS-P1 shortens sneezing for approximately 10 days, nasal discharge for approximately 14 days, blocked nose for approximately 11 days, and cough for approximately 6 days.”
The study did not identify any clinically significant effects in the immunity tests, inflammatory markers, physical examination and peripheral blood examination in any group. There were no side effects or adverse events.
The researchers acknowledged several limitations including the reliance on subjective reporting of cold-like symptoms and suggested that future studies verify curcumin’s effects through physician diagnosis.
Source: Journal of Dietary supplements
Published online 2023 March 16 doi: 10.1080/19390211.2023.2185723
“Effects of Highly Bioavailable Curcumin Supplementation on Common Cold Symptoms and Immune and Inflammatory Functions in Healthy Japanese Subjects: A Randomized Controlled Study.”
Authors: Y. Kuwabara, et al