IJMABHR International Journal of Medical and All Body Health ResearchIJMABHR 2582-8940 Anfo Publication House 330 10.54660/IJMBHR.2021.2.1.41-49 Impact of BMI and Menstrual Cycle Phases on Salivary Amylase: A Physiological and Biochemical Perspective AjayiSimeon Ayo-Oluwa AkanjiOlayemi Oluwatosin Department of Medicine and Surgery, College of Health Sciences, Bowen University, Iwo, Osun State, Nigeria 2021 2 1 41 49 02012021 05022021 CC BY-NC-SA 4.0

Salivary amylase, a key enzyme in the initial digestion of dietary starch, also serves as a biomarker for stress, autonomic nervous system activity, and various physiological states. Its activity is influenced by several factors, including body mass index (BMI) and hormonal fluctuations associated with the menstrual cycle. This article explores the physiological and biochemical interactions between BMI, menstrual cycle phases, and salivary amylase activity, aiming to clarify their interconnected roles and potential clinical implications. Obesity and underweight conditions are associated with metabolic alterations that may affect the salivary glands' function and enzyme secretion. Individuals with higher BMI often exhibit altered sympathetic nervous system activity and systemic inflammation, which can modulate salivary amylase output. Conversely, low BMI may be linked to reduced glandular stimulation or nutritional deficiencies, affecting enzyme levels. These variations highlight BMI as a significant modifier of salivary biomarkers, including amylase. Moreover, the menstrual cycle introduces cyclic hormonal changes primarily in estrogen and progesterone that influence various physiological systems, including salivary gland function. Research suggests that salivary amylase activity fluctuates across the menstrual phases, with notable differences observed between the follicular and luteal phases, possibly due to the hormonal regulation of autonomic tone and glandular secretions. Understanding these interactions is vital for the appropriate interpretation of salivary amylase levels in both clinical and research settings. It also provides insight into broader metabolic and endocrine functions and supports the potential use of salivary amylase as a non-invasive biomarker for assessing physiological status. This article synthesizes current findings and identifies gaps in the literature, suggesting directions for future research to enhance our comprehension of how BMI and menstrual physiology jointly influence salivary biomarkers.

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