Tongkat ali is sometimes marketed as a supplement that can help lower oestrogen levels in the body, although there is limited scientific evidence to support this claim. Oestrogen is a hormone that plays an important role in regulating the menstrual cycle, maintaining bone density, and supporting brain health. abnormal levels of oestrogen can lead to a variety of health issues. While some preliminary studies suggest that tongkat ali may have an impact on hormones, including oestrogen, more research is needed to fully understand its effects.