Ameliorating implications of Psidium guajava L. (guava) leaf against metabolic syndromes—A review

Metabolic syndrome is a cluster of diseases that includes hyperglycemia, hyperlipidemia, hypertension, and obesity that puts people at risk of deadly diseases. The major cause of metabolic syndrome is a sedentary lifestyle and poor dietary choices. Psidium guajava (Guava) leaves have potential health-beneficial effects which can reduce the outcomes of metabolic syndrome or can help in the prevention of the above-mentioned diseases. Several scientific studies have shown guava leaves’ alleviating effects against metabolic syndrome, and it has unique therapeutic and medicinal properties. Secondary metabolites and minerals in the guava leaves such as quercetin, catechin, guajavein, apigenin, phenolic compounds, and flavonoids promote the glucose uptake mechanism of the liver, reverse cholesterol transport system in blood and many other processes that ultimately provide therapeutic benefits. Guava leaves are used as decoctions, powder, and extracts. Different doses are used in different forms of pills, and capsules. This review focuses on the ameliorating effects of guava leaf against metabolic syndrome. The active components reduce glucose levels by stimulating insulin secretion and activating muscle and liver cells to uptake glucose from the blood. Hypertension is controlled by regulating the renin-angiotensin-aldosterone system and nitric oxide secretion in the body. Obesity is controlled by preventing fat accumulation in the body and hyperlipidemia is prevented by decreasing triglyceride levels. The review is supported by different scientific studies done against diabetes, hyperlipidemia, hypertension, and obesity using guava leaf as a natural drug. • Metabolic syndrome includes hypertension, diabetes, hyperlipidemia, and obesity. • Guava leaves are effective in treating metabolic syndrome. • Quercetin, catechin, and gallic acid are major phytochemicals in guava leaf. • Quercetin in guava leaf promotes glycogen synthesis and also controls obesity.