The Effects on Bodyweight

Study - Effects of Persea americana Mill (Aka Avocado) leaf extracts on body ​weight and liver lipids. 
This study was completed by The African Journal of Biotechnology Vol. 6 (8), pp. 1007-1011, 16 April 2007. 

Lifestyle changes accompanying industrialization have a significant impact on the health of the people. The modernization of societies appears to result in a dietary pattern that is high in saturated fats and refined sugars and is low in fibre content. Analyses of available aggregate data sources indicate that a shift towards “western diets” high in saturated fat and sugar and low in fibre is occurring (Reddy and Yusuf, 1998; Popkin, 2002). In Nigeria, there appears to be a cultural transition towards a more westernized lifestyle. The traditional foods consisting mainly of roots, cereals, beans, tubers and vegetables are giving way to fatty foods, sweet snacks and drinks which have too much calories. These changes in dietary pattern among Nigerians, coupled with changes in physical activity patterns, increased use of tobacco products and alcohol are possible causes of hyperlipidaemia and obesity which are becoming important factors in the pathogenesis of chronic degenerative diseases such as cardiovascular disease, diabetes and cancer.
It has been postulated that in many individuals excess weight gives rise to cardiovascular disease, type 2 diabetes mellitus, hypertension, stroke, dyslipidaemia, osteoarthritis, and some cancers (Eckel et al., 2006; Burton et al., 1985; Ezzati et al., 2005). It is also known that fatty liver disease is associated with hyperlipidaemi and obesity (Sharadi and Eldad, 2000). Plants were the major source of materials which the ancient man resorted to for combating various ailments and thus preserving his health (Akah and Ekekwe, 1995). At present, a number of botanicals are still being used in folk-medicine for treatment of different diseases.
Persea americana (avocado) is an almost evergreen tree belonging to the laurel family,  Lauraceae. It is indigenous to Central and South America but is now cultivated in the United States, Asia, parts of Europe and tropical Africa. The leaves are alternate, dark green and glossy on the upper surface, whitish on the underside; variable in shape.
According to Morton (1987), avocado has many medicinal uses. The leaves are chewed as a remedy for gum infections (Periodontitis). The aqueous extract of the leaves has a prolonged antihypertensive effect. The leaf decoction is taken as a remedy for diarrhea, sore throat and bleeding. It allegedly stimulates and regulates menstruation. Recently, the aqueous leaf extract of P. Americana was reported to possess hypoglycemic activity (Antia et al., 2005). The purpose of this study was to test whether the leaf extract of P. Americana would influence body weight gain and liver lipid levels in a rat model.
Rats that were treated with both aqueous and methanolic avocado leaf extracts showed decrease in overall body weight gain (14 and 25%, respectively) compared to the hyperlipidaemic control (Figure 1).
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