The American Herbal Products Association (AHPA) regularly reviews scientific literature for new research that may be useful to the herbal products and supplement industries. The following are some recent articles published in peer-reviewed journals.

Botanical Drugs and Supplements Affecting the Immune Response in the Time of COVID-19: Implications for Research and Clinical Practice
In the times of the current COVID-19 pandemic, discussions of potential benefits of botanical drugs and supplements have emerged globally, although controversial efficacy claims are rightly a concern. A group of phytotherapy researchers have here reviewed the traditional, empirical, and clinical evidence that botanicals can offer some protection and alleviation of viral disease symptoms as well as promoting general well-being. Botanicals have an established role in everyday healthcare, but, since botanical preparations contain many chemical constituents rather than single compounds, challenges arise in demonstrating efficacy and safety. Newly emerging viral infections, like COVID-19, represent a unique challenge in their novelty and absence of established antiviral treatment or immunization. The authors discuss the roles and limitations of phytotherapy in helping to prevent and address viral infections, especially regarding their effects on immune response. Botanicals with documented immunomodulatory, immunostimulatory, and anti-inflammatory effects include adaptogens, Boswellia spp., Curcuma longa, Echinacea spp., Glycyrrhiza spp., medicinal fungi, Pelargonium sidoides, salicylate-yielding herbs, and Sambucus spp. This review provides an introduction to viral immunity and relevant clinical endpoints, as well as a clinical perspective on applications and safety of these herbs in prevention, onset, progression, and convalescence from respiratory viral infections.

Phytotherapy Research, December 2020
DOI: 10.1002/ptr.7008

Kava: A Review of the Challenges and Promise for Modern Use of a Traditional Herbal Beverage
Kava (Piper methysticum Forst.) is a plant with a long history of traditional use in Oceania; a beverage made from the roots is considered sacred and consumed ceremonially in pacific island settings such as Hawaii, Vanuatu, Fiji, and Samoa. Kava extract preparations have been used to treat anxiety in Europe; studies suggest that kava may have anti-inflammatory and anti-cancer effects, in addition to the well-documented anxiolytic activity. Kava is marketed as a dietary supplement in the U.S. and is gaining popularity as a relaxing drink. The authors provide a broad overview on kava use and its related research with a historical background for different uses and discuss the current state of the research, including chemical composition, possible mechanisms of action, and therapeutic potential in treating inflammatory and neurological conditions, as well as cancer. Also discussed are the challenges associated with kava use and research, focusing on the need for the detailed characterization of kava components and associated risks such as its reported hepatotoxicity. This review emphasizes the urgent need for quality control and quality assurance of kava products, as well as further studies on pharmacokinetics, absorption, distribution, metabolism, excretion, and foundational pharmacology.

Nutrients, October 2020
DOI: 10.3390/nu12103044

Milk Thistle (Silybum marianum (L.) Gaertn.): Phytochemistry, Ethnopharmacology and Clinical Evidence
The authors of this study review the traditional uses, pharmacological benefits, and phytochemical composition of milk thistle (Silybum marianum) materials, and also discuss metabolomic analyses and bioavailability. An extensive literature search was conducted using relevant keywords and papers with rationale methodology and robust data selected for review. Clinical studies involving milk thistle or its main constituents are discussed, as well as in vitro and animal studies involving hepatoprotective, anti-diabetic, cardiovascular protection, anti-cancer, and antimicrobial activities. Milk thistle materials have been the subject of thousands of ethnopharmacological, experimental, and clinical investigations. The study concluded that milk thistle is a widely consumed herb with a history of traditional uses and many scientific investigations focusing on its benefits and properties, however, more data are needed on clinical efficiency; and future studies on S. marianum should include studies of metabolism, pharmacokinetics, and bioavailability.

Journal of Ethnopharmacology, January 2021
DOI: https://doi.org/10.1016/j.jep.2020.113303

Turmeric/Curcumin and Health Outcomes: A Meta-Review of Systematic Reviews
Turmeric is one of the most popular herbal products in recent years, and there is a rapidly growing body of research data on various therapeutic uses. The aim of this work was to conduct a meta-review of systematic reviews (SRs) to provide an update for practitioners and researchers on turmeric as a therapeutic. Reviews that evaluated the use of oral turmeric products with a placebo or standard care arm for the treatment of different health conditions were selected. Analysts retrieved 65 SRs covering 20 disease topics. There was moderate quality evidence to support the use of turmeric/curcumin for relieving pain and improving physical function in osteoarthritis. There was low quality evidence for its use in metabolic syndrome, inflammatory conditions and other diseases. The SR data suggested that whole turmeric and bioavailability-enhanced preparations may be useful for different conditions. Turmeric was safe and well tolerated. The authors suggest future research should accommodate the complexity of turmeric medicines when designing studies to inform research and clinical decisions.

European Journal of Integrative Medicine, November 2020
DOI: https://doi.org/10.1016/j.eujim.2020.101252

Effect of Flaxseed Oil on Glycemic Control and Inflammatory Markers in Overweight Adults with Pre-Diabetes: A Double-Blind Randomized Controlled Clinical Trial
The aim of this study was to evaluate the effect of flaxseed oil supplementation on insulin resistance (IR) indices and inflammatory indices in overweight pre-diabetes patients. In this double-blind, randomized clinical trial, 40 overweight pre-diabetic patients were divided into two groups: flaxseed oil (two 1,000-mg capsules per day) and control group who received placebo for 14 weeks. The results indicated a significant decrease in the weight and BMI in the treatment group, in comparison to the basic state (p = 0.001). Insulin and sensitivity of beta-cells diminished significantly in the flaxseed group, when compared to the baseline (p = 0.001). The authors conclude that a 14-week flaxseed oil supplementation may improve the weight and BMI with no effect on glycemic and inflammatory indices in pre-diabetic patients.

Journal of Herbal Medicine, December 2020
https://doi.org/10.1016/j.hermed.2020.100387

Effects of Ajwa Date Seed Powder on Serum Lipids in Humans: A Randomized, Double-Blind, Placebo- Controlled Clinical Trial
High cholesterol is one of the common risk factors of cardiovascular disease. The effects of Ajwa date seed powder on serum lipid profile in human beings were evaluated in this randomized, double-blind, placebo-controlled clinical study. Patients with hyperlipidemia were instructed to take the Ajwa date seed powder (200 mg seed) three times daily after a meal for 90 days for each of two groups, intervention (n = 30) or placebo (n = 28). Each group was similar in essential baseline characteristics with no significant differences. The primary outcome measure was total cholesterol (TC) levels. Secondary outcome measures were low-density lipoprotein (LDL), triglycerides (TG) and high-density lipoprotein (HDL). The Ajwa date seed powder yielded a 19.4%, 22.5%, and 25.78% decrease in total cholesterol (TC), low-density lipoprotein (LDL), and triglycerides (TG) levels, respectively, along with an increase in high-density lipoprotein (HDL) levels by 23.81% in the intervention group; and these values were significantly better than those of the placebo group. In summary, Ajwa date seed powder was found to have positive effects by improving serum lipid profile in the intervention group compared to the placebo group.

Journal of Herbal Medicine, December 2020
https://doi.org/10.1016/j.hermed.2020.100409

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Holly Johnson, PhD
American Herbal Products Association (AHPA)

Holly E. Johnson PhD, is the chief science officer at the American Herbal Products Association (AHPA) where she is the primary scientific resource for the organization, providing individualized technical guidance to member organizations and helping the herbal industry use the latest science, technology and research to ensure consumers continue to have informed access to innovative, safe and effective herbal products. Dr. Johnson took her PhD in Pharmacognosy at the College of Pharmacy, University of Illinois – Chicago (UIC), under renowned Pharmacognosist and researcher Dr. Norman Farnsworth. She is currently a Research Associate with the National Tropical Botanical Garden and serves on AOAC Stakeholders Panels and Expert Review Panels for Foods and Dietary Supplements. She is a member of the USP Medical Cannabis Expert Panel, the Editorial Board of the AOAC International Journal, and also serves on the Advisory Boards of the American Botanical Council and the American Herbal Pharmacoepia. She can be reached at hjohnson@ahpa.org; 301-588-1171, ext. 103.