# Diet and Asthma: A Narrative Review
## 5 Discussion  
The relationship between diet and asthma is complex and multifactorial. Fruits and vegetables have been shown to exert beneficial effects on asthma and airway inflammation [47, 56, 62]. It is also worth noting the significance of dietary diversity, especially in terms of consuming a variety of vegetables, as a relevant factor to consider for asthma [56]. The positive effects of fruits and vegetables on asthma is likely attributed to their high content of polyphenols, vitamins, minerals, bioactive compounds, and fiber [47, 56, 62]. Taking this into consideration, the inclusion of vegetables and fruits in the dietary pattern emerges as a preventive measure against asthma [61, 62]. However, it is important to emphasize the significance of incorporating a diverse range of vegetables and fruits to maximize their potential benefits [117]. In addition to their potential protective effects against the development of asthma, these food groups have also shown promise in managing asthmatic symptoms. Studies have indicated that a higher consumption of fruits and vegetables is associated with improved asthma control [59] as well as better lung function parameters [54]. Therefore, advocating for the inclusion of a wide variety of vegetables and fruits in the diet holds significant potential for both asthma prevention and management strategies. Fiber has also been found to exert a protective effect on airway inflammation and on asthma [37, 68]. This association is also reinforced as many fiber-rich foods contain antioxidants and bioactive compounds, which may help to reduce oxidative stress and inflammation [48]. Overall, incorporating fiber-rich foods into the diet may be a beneficial dietary intervention for individuals with asthma, potentially reducing airway inflammation and improving lung function. However, further research is needed to fully understand the mechanisms by which fiber exerts its protective effects, and to identify the optimal amount and types of fiber for asthma management. In contrast, the effects of dietary fats on asthma are more nuanced [76, 77]. Saturated and trans fats have been linked to negative health outcomes, including an increased risk of poor asthma disease outcomes [48, 77]. On the other hand, monounsaturated and polyunsaturated fat, such as those found in olive oil (oleic acid) and fatty fish (EPA and DHA), have been associated with a decreased risk of asthma and inflammation [79, 80]. However, the effects of omega-3 and fish oil supplementation on asthma are less clear. While fatty fish, the primary source of omega-3 fatty acids, has been shown to have a beneficial effect on this disease, the same is not necessarily true for omega-3 or fish oil supplements [85, 118]. Whole fish contains a variety of nutrients and bioactive compounds, such as proteins, vitamins, minerals, and omega-3 fatty acids, which work together synergistically to provide health benefits [85, 118]. Fish oil supplements typically provide isolated forms of EPA and DHA that lack the complex mixture of nutrients and other bioactive compounds present in whole fish [85]. It is possible that the components of the whole fish work in concert to provide optimal health benefits and optimal absorption of EPA and DHA [119]. Moreover, the context in which fish has been consumed, such as in the Mediterranean diet or other healthy patterns, often includes a variety of other beneficial foods that contribute to overall health. While more research is still needed to investigate the benefits of fish oil supplements, obtaining nutrients through a varied and balanced diet that includes whole fish is generally considered the preferred approach for maximizing health benefits. Additionally, in terms of maternal fish consumption, two studies found no significant association between the frequency of fish consumption during pregnancy and the risk of asthma in children [82].