Achillea millefolium is an orexigenic (appetite-stimulant) herb. A study evaluated the possible orexigenic effect of hydro-alcoholic extract of A. millefolium by measuring the plasma ghrelin level.

Thirty experimental models were segregated into five groups of six models each. Control group was given water while treatment groups received 50, 100 or 150 mg/kg of A. millefolium extract for 7 days. Prior to the intervention, daily amount of the food eaten by each model was quantified for 10 days. During the investigation, the amount of energy intake of each model was estimated 1, 2, 4, 6 and 24 hr after each intake, for a period of 7 days.

In the second part of the study, following the administration of selected extract concentration, blood samples were collected at intervals to measure plasma ghrelin levels. Twelve rats were randomly selected and divided into 2 groups of 6 models each.

The orexigenic dose of extract and distilled water was then fed to two separate groups of 6 experimental models. Plasma ghrelin level was assessed 0.5, 1, 2 and 4 hr after extract intake.

It was noted that the change in energy intake after treatment with 50 and 100 mg/kg of the extract was significantly higher compared to the other groups. Administration of 100mg/kg herb extract led to a significant reduction in ghrelin level one hr after intervention; however, there was no significant difference among control and treated group.

The study points to a positive dose-related effect of A. millefolium on appetite. The orexigenic activity of the extract seems not to be related to changes in plasma ghrelin levels.

Source: Nematy M, Mazidi M, Jafari A, et al. The effect of hydro-alcoholic extract of Achillea millefolium on appetite hormone in rats. Avicenna Journal of Phytomedicine 2017;7(1):10-15.