**11. Conclusion**

Flaxseed is one of the richest herbs in terms of nutrients and active compounds. This herb is known as one of the best dietary sources of omega-3 fatty acids and lignan. This herb is used in different forms, the most common of which are the whole flaxseed, ground flaxseed, and flaxseed oil. Several methods are used to extract flaxseed oil from full flaxseed, from mechanical methods that are part of traditional methods to more modern methods such as microwave and ultrasonic-assisted extraction methods. In recent years, several studies have been conducted on the beneficial properties of flaxseed in the prevention and treatment of chronic diseases as an alternative treatment, which include anti-inflammatory, antioxidant, anti-obesity effects, improved lipid profile, and reduced risk of cardiovascular diseases. Part of these beneficial effects of this plant is due to its high content of lignans. Despite the mentioned beneficial effects, there are also some concerns related to the use of this plant, such as the risk of oxidation of flaxseed oil in higher temperature due to higher content of PUFA and flaxseed contamination with toxins and heavy metals. Also, some researchers have reported concerns regarding the use of this plant in people with hormone-dependent cancers such as breast and ovarian cancer due to its phytoestrogens. Therefore, there is a need for more studies related to the different aspects of using this plant in the daily diet as well as in the prevention and treatment of chronic diseases.
