**4.3 Antioxidants**

Rose hips are an exceptional source of antioxidants. In a study where over 3100 foods from around the world were tested, rose hip from *R. canina* was one of the foods with the highest antioxidant content among berries, fruits, and vegetables (**Figure 4**) [55]. In another study where rose hips from different species were compared, the fruits from *R. rugosa* had a slightly lower antioxidant content than fruits from *R. canina* [29].

Dietary antioxidants protect the cells and tissue against free radicals and radical oxygen species (ROS). ROS are a group of highly reactive chemicals containing oxygen that are produced either exogenously or endogenously, during normal biological functions such as immune response, cell differentiation, growth, and proliferation. Overactivity of ROS has been associated with a wide variety of human disorders, such as chronic inflammation, age-related diseases, and cancers.

#### **Figure 4.**

*Antioxidant content of different foods and drinks (mmol/100 g). The content of antioxidants is measured by the FRAP-method. Sources: [55, 56].*

#### *Rose Hip as a Nutraceutical DOI: http://dx.doi.org/10.5772/intechopen.105392*

An example of this is seen in the bloodstream where vitamin C, along with other antioxidants, protects LDL-cholesterol, thus preventing the fatty acid molecule from getting stuck the arteries, in an event that can ultimately lead to arteriosclerosis [57]. ROS are constantly produced in the body, creating a demand for a steady supply of antioxidants from the diet to keep the reactive species in check. An imbalance of ROS and antioxidants, which results in an excess of the ROS, can lead to oxidative stress, a condition akin to overactivity of ROS [35] and therefore, any of the human disorders [49]. Some of the main antioxidants found in rose hips from the two species include vitamin C, E, and A, beta-carotene, lycopene, and flavonoids. **Figure 4** shows the antioxidant content in *R. canina* fruits and other selected foods measured by the FRAP-method (Ferric Reducing Ability of Plasma), one of several ways of measuring the antioxidant content in foods.
