Contents lists available at ScienceDirect Journal of Functional Foods journal homepage: www.elsevier.com/locate/jff Royal jelly is an effective and relatively safe alternative approach to blood lipid modulation: A meta-analysis Amir Hadi a , Ameneh Najafgholizadeh b , Elham Smadi Aydenlu c , Zahra Shafiei d , Fatemeh Pirivand e , Sahar Golpour a , Makan Pourmasoumi a, ⁎ a Food Security Research Center and Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, Isfahan, Iran b Department of Microbiology, Islamic Azad University, Naein Branch, Naein, Iran c Faculty of Nursing and Midwifery, Urmia University of Medical Sciences, West Azerbaijan, Iran d Health Information Technology, Iran University of Medical Sciences, Tehran, Iran e Surgical Technology, Shahid Beheshti Medical University, Tehran, Iran ARTICLE INFO Keywords: Royal Jelly Total cholesterol Low-density lipoprotein cholesterol High-density lipoprotein cholesterol Triacylglycerol Systematic review Meta-analysis ABSTRACT Royal jelly is a functional food with several health promoting properties. The aim of present meta-analysis was to examine the role of royal jelly in blood lipid profiles. We systemically searched PUBMED, the Cochrane Library, Scopus, Web of Science and Google Scholar to identify eligible studies up to July 2017. Clinical trials which investigated the efficacy of royal jelly on adult blood lipid parameters were included. A random effects model was used for quantitative data synthesis. The pooled analysis of six trials suggested that royal jelly reduces total cholesterol blood levels. No significant change was observed in triglycerides, low-density lipoprotein cholesterol and high-density lipoprotein cholesterol blood concentrations. Subgroup analysis revealed a greater impact of RJ on the decrease of Total cholesterol and the increase of high-density lipoprotein cholesterol levels in studies with a long-term follow-up (≥90). This meta-analysis suggested that Royal jelly consumption might effective on improvement of lipid parameters. 1. Introduction Dyslipidemia is a leading risk factor for the development of CVD, characterized by elevated levels of low-density lipoprotein cholesterol (LDL-C) and/or triacylglycerol (TG), and/or reduced levels of high- density lipoprotein cholesterol (HDL-C) (Sahebkar, 2017). Poor control of dyslipidemia is related to a set of problems that reduces quality of life, increases mortality and imposes huge costs on social healthcare systems (Yusuf, Reddy, Ounpuu, & Anand, 2001). There is well-estab- lished evidence for the efficacy of common drugs to treat dyslipidemia, even though most of them possess considerable adverse effects (Sahebkar, 2017; Yan et al., 2006). Over recent decades, evidence shows a growing interest in finding natural alternatives to lipid-mod- ifying therapy (Parikh, Parikh, & Kothari, 2014). The lack of sufficient information in understanding the effects of medicinal plants on the disease and its possible side-effects is an important problem faced by doctors (Bahmani et al., 2015). Royal jelly (RJ) is a milky viscous substance and one of the most interesting functional foods (Nagai & Inoue, 2004; Pourmoradian, Mahdavi, Mobasseri, Faramarzi, & Mobasseri, 2014). RJ is produced primarily from the hypopharyngeal and mandibular secretory glands of young worker bees (Apis mellifera)(Buttstedt, Moritz, & Erler, 2014), and is composed of water, carbohydrates, proteins, free amino acids, lipids, vitamins (mainly thiamine, niacin, riboflavin), minerals (mainly iron and calcium) and significant amounts of bioactive substances (Bincoletto, Eberlin, Figueiredo, Luengo, & Queiroz, 2005). Today, RJ is widely utilized in many countries as a commercial product, especially in food supplements and cosmetics (Ramadan & Al-Ghamdi, 2012). RJ has been used as a human medicine and shown to possess several pharmacological effects, including immunomodulatory (Okamoto et al., 2003), antioxidant (Nakajima, Tsuruma, Shimazawa, Mishima, & Hara, 2009) antitumor (Townsend, Brown, Felauer, & Hazlett, 1961; Townsend et al., 1960), neurogenesis-promoting (Hattori, Nomoto, Fukumitsu, Mishima, & Furukawa, 2007) and vasoactive properties (Matsui et al., 2002). Evidence from animal studies has documented the potential benefits of RJ consumption on lipid metabolism (Nakajin, Okiyama, Yamashita, Akiyama, & Shinoda, 1982; Vittek, 1995). Also, the lipid-lowering characteristics of RJ have been addressed in some human studies (Chiu et al., 2017; Lambrinoudaki et al., 2016), whereas others have not suggested any improvement (Morita et al., 2012). https://doi.org/10.1016/j.jff.2017.12.005 Received 9 September 2017; Received in revised form 2 December 2017; Accepted 3 December 2017 ⁎ Corresponding author at: Department of Community Nutrition, School of Nutrition and Food Science, Isfahan University of Medical Sciences, PO Box 81745, Isfahan, Iran. E-mail address: makan.pourmasoumi@nutr.mui.ac.ir (M. Pourmasoumi). Journal of Functional Foods 41 (2018) 202–209 1756-4646/ © 2017 Elsevier Ltd. All rights reserved. T