Review on Health Benefits of Fruit and Vegetables Consumption: Preventive Implications for Non-communicable Diseases in Ethiopia

Globally, the low consumption of fruit and vegetables (FV) below the requirement is contributed to increase the incidence of non-communicable diseases (NCDs) like obesity, cardio vascular disease, cancers and leading cause of death worldwide. Therefore, the objective of this review was to document existing information concerning the health benefits of FV consumption and their potential role for the prevention of NCDs in Ethiopia. Related and published researches have reviewed and discussed critically. In Ethiopia, the total domestic consumption of fresh FV was estimated at 760,000 metric tons however, low FV was consumed (1.5%) compared to other regions of the world. Ethiopia’s per capita consumption of fresh fruits is approximately 7kg/person/year which is far below the recommended minimum level of dietary intake (146kg/person/year). The review also showed that the burden of NCDs in Ethiopia is increasing and estimated to account for 30% of total deaths. Despite the increasing burden of NCDs, health systems and public health policies have been mostly focused on controlling infectious diseases, under nutrition and micronutrient deficiencies. A comprehensive strategic action plan for the prevention and control of NCDs and its associated risk factors was also developed in the country but, there is a need for a better understanding of the burden of dietary risk factors and their contribution to NCDs to achieve the goals of the strategic plan effectively and efficiently. Moreover, this review identified that family income, lower paternal educational, poor nutritional knowledge and practice issues were associated to low FV consumption. However, there are no adequate data at national level in Ethiopia to identify barriers to low FV consumption. Fruit and vegetables intake need to be promoted through mass media, nutrition education intervention and multi-sectorial approaches to prevent non-communicable diseases.


Introduction
Fruit and vegetables (FV) consumption is crucial to the availability of micronutrients to the body as they are a rich of vitamins and minerals which are required for the normal functioning of the human body (Ruel et al., 2011b;Oyebode et al., 2014). They are also rich in fiber, phytochemicals, essential micronutrients, which act as antioxidants like vitamin A, C and E (Slavin & Lloyd, 2012).
According to the Centers for Disease Control and Prevention (CDC), eating more FV is associated with lower low density lipoprotein cholesterol levels and it is an important part of a weight management strategy to reduce the risk of cancer (CDC, 2011). Consumption of FV is also associated with a reduced risk of obesity, cancers cardio vascular disease (CVD) (Ruel et al., 2011b). Therefore, FV are an important component of a healthy diet and, if consumed daily in sufficient amounts, it could reduce major diseases such as CVDs and certain cancers.
Despite an increasing focus on the health benefits of FV, their consumption is below the recommended intake among adults (MMWR, 2010). According to the World Health Organization (WHO), adequate FV intake entails a consumption of at least 400g of FV per day (Ruel et al., 2011b). However, adults across the United States exhibit an overall low consumption of FV (Lee-Kwan et al., 2017). Globally, the low consumption of FV below the requirement is contributed to increase the incidence of CVDs and cancers; the two leading causes of death worldwide (Ruel et al., 2011b. For example, NCDs are currently the leading cause of death which accounts 70% worldwide (WHO, 2017).
The WHO estimated that low FV consumption contribute to approximately 2.7 million deaths per year from chronic diseases, 11% of CVDs and 31% of ischemic heart diseases worldwide (Ruel et al., 2005a). Low consumption of FV has also been ranked the sixth major risk factor for mortality in the world (Ruel et al., 2005a). The incidences of these chronic diseases are increasing in developing countries due to their life style and dietary Journal of Medicine, Physiology and Biophysics www.iiste.org ISSN 2422-8427 An International Peer-reviewed Journal Vol.70, 2021 17 changes. The high prevalence of micronutrient deficiencies in developing countries has been attributed to the low knowledge of the nutritional value of these fruits and vegetables (Hart et al., 2005).
Moreover, a study was done by the WHO to determine which developed countries had national average FV consumptions which were within recommended values and out of the 21 studied countries, only Israel, Spain and Italy had acceptable national average intakes of at least 400g/day (Ruel et al., 2005a). It has been noted that even in developed countries, the intake of fruit and vegetables is lower (CDC, 2011); and this could be due to low knowledge and attitude regarding FV intake.
In Ethiopia, the total domestic consumption of fresh fruits was estimated at 760,000 metric tons. However, low FV is consumed in Ethiopia compared to other regions of the world. For instances, Ethiopia's per capita consumption of fresh fruits is approximately 7 kg/person/year which is far below the WHO and FAO recommended minimum level of dietary intake (146kg/person/year). The prevalence of FV consumption in Ethiopia was very low 1.5% (Terefe et al., 2018).
The burden of NCDs in Ethiopia is also increasing and was estimated to account for 30% of total deaths (WHO, 2014). The estimated age-standardized death rates of all NCDs in Ethiopia were 556.1 per 100 000 population in men and 404.2 in women, and over 60% of NCDs related deaths occurred among those under 70 years old (WHO, 2014). Prevalence of overweight was estimated to be increasing, while many people are still undernourished (Tebakaw et al., 2014). Despite the increasing burden of NCDs, health systems and public health policies have been mostly focused on controlling infectious diseases, under nutrition and micronutrient deficiencies.
Ethiopia has developed a comprehensive strategic action plan for the prevention and control of NCDs and its associated risk factors (EPHI, 2016). Whilst the strategic plan is helpful in guiding interventions, there is a need for a better understanding of the burden of dietary risk factors and their contribution to NCDs in order to achieve the goals of the strategic plan effectively and efficiently. However, there are no adequate national level data or surveillance systems to identify risk factors. Therefore, the main objective of this review was to document existing information on the health benefits of FV consumption and their potential role for the prevention of NCDs in Ethiopia.

Related Literature Review 2.1 Health Benefits of Fruit and Vegetables
Eating a diet rich in FV as part of an overall healthy diet can help protect against a number of serious and costly chronic diseases, including heart disease, type II diabetes, some cancers, and obesity. FV are a significant source of water and nutrients such as vitamins, minerals, and fiber that help the human body work as it should and fight off illness and disease (US, 2015). FV have components that give them nourishing properties, appearance, texture, and color specific to this group of foods (Morillas & Delgado, 2012). Phytochemicals in FV are mostly responsible for a protective effect against stomach, colon, breast, lung and prostate cancer diseases. Phytochemicals like phenolic acids & flavonoids are rich in FV (Mcguire, 2011), and they are known as natural secondary plant metabolites that mainly provide protection against abiotic or biotic stress. Sufficient intake of FV has been related epidemiologically with reduced risk of many non-communicable diseases. Higher total FV intake is also associated with lower risk of cognitive decline hence proved beneficial for mental health (Payne et al., 2012). Much interest are focused on the vital role of antioxidants which impart bright color to FV and act as scavengers cleaning up free radicals before they cause detrimental health effects (Kaur & Kapoor, 2001). Moreover, fibers found in FV have been shown to reduce intestinal passage rates by forming a bulk, leading to a more gradual nutrient absorption (Anderson et al., 20105); hence preventing constipation. They can be fermented in the colon, increasing the concentration of short chain fatty acids having anti-carcinogenic properties and maintaining gut health (Lattimer & Haub, 2010 (Tsegaye et al., 2009).  (Ruel, 2005a)

Fruits and Vegetables Consumption
It is widely accepted that FV are important component of a healthy diet and that the consumption can help prevent a wide range of diseases. The WHO and FAO recommends a minimum of 400g of fruit and vegetables per day for the prevention of chronic diseases as well as for the prevention and alleviation of several micronutrient deficiencies. Despite the growth recorded in the global FV production and trade, the food consumption per capita in Africa is still below the recommended 400 gram of FV per day (=146 kg/person/year. The substantial shortages in utilization are confirmed by the levels of FV consumption in Sub-Saharan African countries. A study done in ten different countries including Ethiopia, Kenya, Ghana, Rwanda and Uganda show that consumption ranges from 27 to 114 kg per person per year, which is far below the recommended amount (Ruel et al., 2005a). Except for Kenya, the majority of the households consume less than the minimum amount of FV recommended by the WHO and FAO.

Barriers to Fruit and Vegetables consumption
The major preventable risk factor contributing to the burden of disease worldwide is a poor diet like inadequate FV consumption (EPHI, 2016;WHO, 2016). Health problems are related to specific nutrients (Galland, 2010), and overall eating habits ( Barbresko et al., 2013), while disease factors are generally associated with foods or dietary habits, with or without the presence of obesity (Calder et al., 2011). Another study done in US showed that individuals who consumed high levels of dietary fat and too little fiber and limited fruit and vegetables were most at increased risk of heart disease, stroke, and cancer (Mcguire, 2011).
According to a study done in Brazil, family income, lower paternal educational and consumption of high sugar content beverages were significantly associated with low FV consumption (Valmorbida & Vitolo, 2014). Other barriers such as poor nutritional knowledge and practice, cost, dislike of FV issues were found to be highly predictive of low fruit and vegetable intakes (Appleton et al., 2010).
A nationwide survey conducted in Ethiopia reported that the risk factors of NCDs were low fruit/vegetable intake, low physical activities, overweight, hypertension, and raised fasting blood glucose (EPHI, 2016). Other studies done in Ethiopia and Bangladesh also showed that the risk factors of NCDs were smoking, alcohol consumption, low consumption of FV and low level physical activity (Fessahaye et al., 2012;Zaman et al., 2016). Low consumption of FV is often simplistically attributed to unhealthy diets in developed countries and to