Written by Taylor Woosley, Staff Writer. The meta-analysis of 40 studies including in vivo, in vitro, and clinical trials using components of cinnamon suggests that cinnamon aids in improvement of cognitive functioning such as memory and learning through inhibition of Aβ-induced neurotoxicity.
The fast increase of aging in the global population has led to the acquisition of aging-associated conditions1. Neurodegenerative diseases are a common and growing cause of mortality and morbidity worldwide, particularly in the elderly2. Characteristics of neurodegenerative diseases are often linked to pathological protein formation and, in many cases, high-order aggregate formation which places stress onto neurons and render subsequent cytotoxic events, including an increased number of reactive oxygen species (ROS), inflammation, and mitochondrial dysfunction3.
Cinnamon is a medicinal plant with confirmed effectiveness in the treatment of neurodegenerative disorders4. Cinnamon has been studied for its anti-inflammatory, immunomodulatory, neurotrophic, and antioxidant properties5. Studies investigating the therapeutic efficacy of cinnamon in inflammatory neurodegenerative disorders have revealed that compounds endogenous to cinnamon exerted significant anti-Alzheimer effects through improved insulin signaling and cognitive dysfunction6.
Nakhaee et al. conducted a systemic review to investigate the effect of cinnamon and its components on cognitive function (memory and learning) in humans and other species and cell lines. Study inclusion consisted of studies assessing the effects of cinnamon or its components on cognitive function in humans or animals using behavioral tests. Furthermore, in vitro studies that measured amyloid-β plaque, tau aggregation, and neural survival in cell lines were also considered. Age, gender, species, exposure, sample size, and duration of intervention were not restricted in this systemic review.
40 studies were included in the final analysis and consisted of three categories: in vivo (n=33), in vitro (n=5), and clinical trial (n=2). Among the 40 studies, 18 used cinnamon, cinnamon extract, or cinnamon powder, while 22 studies used components of cinnamon such as eugenol, cinnamic acid, or cinnamaldehyde. Effects of these compounds were analyzed on cognitive function (memory and learning) for in vivo studies (n=33), memory for clinical trials (n=2) and Amyloid-Beta (n=3), tau aggregation (n=1) and neural survival (n=1) for in vitro studies. Significant findings of the systemic review are as follows:
- All four in vitro studies reported a positive outcome in a wide range of dosages (10, 15, 20, 23, 25, 100, and 110 µM). Two studies showed an inhibiting effect of Cinnamaldehyde on Amyloid β, two reported an increase in neural survival using Trans-Cinnamaldehyde and Cinnamaldehyde, and one reported the inhibiting effects of cinnamaldehyde on tau
- The only in vitro study that used methanol extract from cinnamon bark positively inhibited the Amyloid-Beta 40 production at a dose of 50 µg/mL.
- In general, most in vivo studies reported a positive effect on cognitive function (learning and memory) using a variety of behavioral tests. However, one study reported that 250 mg/kg and 500 mg/kg of cinnamon decreased learning and memory.
Results of the study suggest that cinnamon could have a positive role in improving cognitive function (learning and memory). However, further research is needed to better comprehend what type and amount of cinnamon is considered safe and effective for cognitive improvement. Study limitations include the inability to investigate the dose dependency of the usage of different components of cinnamon and the need to specify the effects of cinnamon and components on learning and memory separately.
Source: Nakhaee, Samaneh, Alireza Kooshki, Ali Hormozi, Aref Akbari, Omid Mehrpour, and Khadijeh Farrokhfall. “Cinnamon and cognitive function: a systematic review of preclinical and clinical studies.” Nutritional Neuroscience (2023): 1-15.
© 2023 Informa UK Limited, trading as Taylor & Francis Group
Click here to read the full text study.
Posted April 5, 2023.
Taylor Woosley studied biology at Purdue University before becoming a 2016 graduate of Columbia College Chicago with a major in Writing. She currently resides in Glen Ellyn, IL.
References:
- Gómez-Gómez ME, Zapico SC. Frailty, Cognitive Decline, Neurodegenerative Diseases and Nutrition Interventions. Int J Mol Sci. Jun 11 2019;20(11)doi:10.3390/ijms20112842
- Erkkinen MG, Kim MO, Geschwind MD. Clinical Neurology and Epidemiology of the Major Neurodegenerative Diseases. Cold Spring Harb Perspect Biol. Apr 2 2018;10(4)doi:10.1101/cshperspect.a033118
- Chi H, Chang HY, Sang TK. Neuronal Cell Death Mechanisms in Major Neurodegenerative Diseases. Int J Mol Sci. Oct 9 2018;19(10)doi:10.3390/ijms19103082
- Sayad-Fathi S, Zaminy A, Babaei P, Yousefbeyk F, Azizi N, Nasiri E. The methanolic extract of Cinnamomum zeylanicum bark improves formaldehyde-induced neurotoxicity through reduction of phospho-tau (Thr231), inflammation, and apoptosis. Excli j. 2020;19:671-686.
- Rangasamy SB, Dasarathi S, Nutakki A, Mukherjee S, Nellivalasa R, Pahan K. Stimulation of Dopamine Production by Sodium Benzoate, a Metabolite of Cinnamon and a Food Additive. J Alzheimers Dis Rep. Apr 23 2021;5(1):295-310. doi:10.3233/adr-210001
- Yulug B, Cankaya S. Translational perspective: is cinnamon a suitable agent for cognitive impairment and Alzheimer’s disease associated with brain trauma? Neural Regen Res. Aug 2019;14(8):1372-1373. doi:10.4103/1673-5374.253518
