*3.1.1 Fruits and vegetables*

There is significant amount that low intake of fruit and vegetable is related to higher risk of CVDs while higher intake is related to low risk of CVDs [86, 87]. Fruits and vegetables are rich sources of polyphenolic compounds such as phenolic acid and flavonoids. Different studies associate the intake of polyphenols foods such as fruit and vegetable with low risk of CVDs [88, 89]. In addition, various studies have shown that the properties of flavonoids such as antioxidants and anti-inflammatory might also improve functions of vascular system [90, 91]. Fruits and vegetables reduce

the risk of CVDs by decreasing vulnerability of low density lipoprotein particles to oxidation [92]. Different types of bioactive compounds found in fruits and vegetables such as dietary fibre, carotenoids, ascorbic acid and minerals such as magnesium and potassium act collaboratively to nurture a comprehensive beneficial effect.

## *3.1.2 Whole grains, legumes and nuts*

Whole grains are more important in terms of nutrition since they have phytochemicals that could work synergistically to decrease the risk of CVDs [93]. Moreover, whole grains are also a rich source of dietary fibre, vitamin B complex and minerals. The preventative effect of whole grains on the risk of CVDs is attributed to their influence on insulin vulnerability, blood pressure and inflammation which is associated with the excessive consumption of antioxidant nutrients available in the germ of whole grains [83, 94, 95]. Legumes are rich source of protein, soluble fibre, micronutrients such as folate and polyphenols [96]. Different bioactive components such as protein, dietary fibre and phytosterols are attributed to the cholesterol-lowering effect of legumes [97]. Nuts are rich sources of mono and polyunsaturated fatty acids, arginine, soluble fibre and various antioxidant polyphenols and these active components contribute to cholesterol lowering effects [71].

### *3.1.3 Fish*

High consumption of fish and fish oil supplements contribute to low incidence of CVDs [98]. Fish is a rich source of omega 3 fatty acids such as docosahexaenoic acid (DHA; 22:6 n-3) and eicosapentaenoic acid (EPA; 20:5 n-3). They are available in oily fish such as salmon, tuna, herring and fish oil. Consumption of fish is associated with low risk for myocardial infarction, which is associated with useful influence of DHA and EPA on plaque fluctuation and modulation of endothelial function [99]. Fish oil supplements have beneficial influence on blood pressure and lipid profile [100, 101]. Moreover, DHA and EPA reduce low density lipoprotein oxidative sensitivity in postmenopause women which might assist in reducing the risk of CVDs [102].

#### *3.1.4 Soy protein*

Soy products are a rich source of polyunsaturated fatty acids, dietary fibre, micronutrients, low saturated fat content and isoflavones [103]. In addition, the protein content of soybean ranges from 35%–40% having all essential amino acids making soy protein comparable to protein of animal source and it is also cholesterol free [104]. Isoflavones prevent the oxidation of low density lipoprotein and reduces the risk of atherosclerosis [76]. Studies done in China among women and Japan demonstrated that a daily consumption of more than 6 g of soy reduces low density lipoprotein-C, total cholesterol, ischaemic and cerebrovascular incidence than consumption of less than 0.5 g [105, 106].

#### *3.1.5 Coffee, tea and chocolate*

Coffee and tea, the most popularly consumed beverages after water, are the chief source of caffeine. Diterpenes such as kahweol and cafestol are suspected to be behind the cardio-protective effect of coffee. Consumption of coffee might potentially decrease the incidence of myocardial infarction, but evidence in this regard is not conclusive [107, 108]. Although results are not consistent, consumption of green tea seems to protect against CVDs [109]. High intake of tea and flavonoids

#### *Role of Functional Food in Treating and Preventing Cardiovascular Diseases DOI: http://dx.doi.org/10.5772/intechopen.96614*

contribute to the primary prevention of IHD and reduced risk of CVDs mortality [109, 110]. Cocoa is the main ingredient in chocolate manufacturing; it is a rich source of flavonoid and it has been lately evaluated for its plausible role in preventing CVDs [111]. The protective effect of chocolate is attributed to the decrease of blood cholesterols levels, substantial increase of high density lipoprotein including marked decrease of oxidised low density lipoprotein [112].
