Nutritional contribution of street foods

The majority of studies demonstrated that street foods contributed significantly to the diet of children and adults in developing countries, both in terms of energy, protein and micronutrient intakes and in terms of food groups consumed (Table 1)⁽ Reference Nago, Lachat and Huybregts ^{3 ,} Reference Mwangi, den Hartog and Foeken ^{4 ,} Reference Chakravarty and Canet ^{6 ,} Reference Webb and Hyatt ^{10 –} Reference Namugumya and Muyanja ^{29 )}.

Energy and nutrient intakes

In terms of nutrient contributions from street foods, the highest contributions of street foods to daily energy intakes in adults were found in Abeokuta in Nigeria (50·3 %EI in males; 48·3 %EI in females)⁽ Reference Oguntona, Razaq and Tolulope ^{13 )}, Ougadougou in Burkino Faso (46 %EI)⁽ Reference Becquey and Martin-Prevel ^{26 )}, Nairobi in Kenya (27–36 %EI in males; 13–22 %EI in females)⁽ Reference Van ‘t Riet, den Hartog and Mwangi ^{22 )}, Uganda (22·4–25·6 % EI)⁽ Reference Namugumya and Muyanja ^{29 )} and Bamako in Mali (18·3 %EI)⁽ Reference Ag Bendech, Chauliac and Malvy ^{15 –} Reference Ag Bendech, Chauliac and Gerbouin-Rerolle ^{17 )}. In children, numerous studies including those in Cotonou in Benin (40 %EI)⁽ Reference Nago, Lachat and Huybregts ^{3 )}, Nairobi in Kenya (13·4–22·4 %EI)⁽ Reference Van ‘t Riet, den Hartog and Mwangi ^{22 )}, Port-au-Prince in Haiti (25 %EI)⁽ Reference Webb and Hyatt ^{10 )}, Bamako in Mali (18·3 %EI)⁽ Reference Ag Bendech, Chauliac and Malvy ^{15 –} Reference Ag Bendech, Chauliac and Gerbouin-Rerolle ^{17 )}, Hyderabad in India (19 %E)⁽ Reference Sujatha, Shatrugna and Narasimha ^{11 )} and rural areas of Kenya (13·5–20·8 %EI in males; 12·8–17·3 %EI in females)⁽ Reference Gewa, Murphy and Neumann ^{25 )} have demonstrated the contribution of street foods to daily energy intake. Moreover, it is important to realize that the energy supplied by street foods usually serves as a replacement for home meals⁽ Reference Chauliac, Bricas and Ategbo ^{30 )}. Furthermore, it needs to be recognized that should the energy from street foods be added to that from regular meals taken at home there may be an increase in energy intake which in the long run will impact detrimentally on weight status.

In terms of protein intake there are fewer data available. In Haiti, street foods contributed 16 % of the protein RDA in secondary-school children⁽ Reference Webb and Hyatt ^{10 )}. In Nigerian adolescents, average daily protein intake (62 g) from street foods provided more than 50 % of the RDA⁽ Reference Oguntona and Kanye ^{12 )}. In Nigerian adults, street foods contributed 53·2 % of males’ and 50·7 % of females’ total daily protein intake⁽ Reference Oguntona, Razaq and Tolulope ^{13 )}. Similarly, in Nairobi, meals sold to workers provided more than 50 % of the RDA for protein⁽ Reference Korir, Imungi and Muroki ^{14 )}. A study in Mali found that street foods provided 41 %, 19 % and 9 % of daily protein intake in persons of high, middle and low SES, respectively⁽ Reference Ag Bendech, Chauliac and Gerbouin-Rerolle ^{16 )}; while a study in Uganda found that street foods contributed 38·6–44·9 % to daily total protein intake⁽ Reference Namugumya and Muyanja ^{29 )}. In Calcutta a typical street meal comprised 20–30 g of protein as measured by proximate analyses⁽ Reference Chakravarty and Canet ^{6 )}. Overall, the majority of studies suggest that street foods contribute significantly to the daily intake of protein, often as much as 50 % of the RDA.

Fewer data are available on fat and carbohydrates. In Cotonou, more than 40 % of fat and carbohydrates came from street foods⁽ Reference Nago, Lachat and Huybregts ^{3 )}. Daily fat intake from street foods was higher in the affluent group, 20–30 %, compared with 15 % in the low-SES group⁽ Reference Nago, Lachat and Huybregts ^{3 )}. In Nigerian adults street foods provided 37·9 % and 54·0 % of total daily intake of fat and carbohydrates, respectively⁽ Reference Oguntona, Razaq and Tolulope ^{13 )}. In Nigerian adolescents street foods provided 70·8 % and 24·8 % of total daily fat and carbohydrate intakes⁽ Reference Oguntona and Kanye ^{12 )}. In Burkina Faso, a study reported on the adequacy of women's diet. Findings were that ready-to-eat foods bought outside the home provided 52 % of daily fat intake and 72 % of sugar intake⁽ Reference Becquey and Martin-Prevel ^{26 )}. In adults in Uganda, street foods accounted for 70·1–93·4 % of daily energy intake and fat contributed 21·9–26·3 %EI⁽ Reference Namugumya and Muyanja ^{29 )}. In Calcutta, an average street food meal of 500 g comprised 12–15 g of fat⁽ Reference Chakravarty and Canet ^{6 )}. The data on fat and carbohydrate intakes are of some concern in terms of the high contribution of street foods to the total intakes of fat and sugar and their role in the development of obesity and non-communicable diseases.

A few studies have provided limited data on the intakes of micronutrients. Among adults in Abeokuta, street foods contributed 35·2 % of Fe intake, 46·2 % of Ca, 55·3 % of vitamin A, 57·3 % of vitamin C and 47·5 % of thiamine intake (total daily intakes)⁽ Reference Oguntona, Razaq and Tolulope ^{13 )}. In adolescents, street foods contributed 64 % of calcium intake, 50 % of Fe, 60 % of vitamin A, 5·5 % of thiamin and 5·5 % of vitamin C intake (total daily intakes)⁽ Reference Oguntona and Kanye ^{12 )}. However, a study in Bamako found that Ca (2·7–8·7 %) from street foods made only a small contribution while vitamin A from street foods made a large contribution (70–278 %)⁽ Reference Ag Bendech, Chauliac and Malvy ^{15 –} Reference Ag Bendech, Chauliac and Gerbouin-Rerolle ^{17 )}. Few studies on street foods have actually analysed their nutrient content by proximate chemical analyses. Similarly, there is a dearth of information on the micronutrient content of street foods.

Despite not having nutrient intake data for saturated fat, trans-fat, sugar (mentioned by a few studies) and salt, there are sufficient data on the types of food and their preparation to realize that these nutrients are found in many popular items purchased from street vendors. Street foods such as candy, chocolates, soft drinks, sweetened tea, cookies and pastries, fried fish and meat, fried bread dough and doughnuts, and crisps are items having one or more of the following: high sugar, high saturated fat, high trans-fat and/or high salt (Table 2). Yet, it should be acknowledged that healthy food items are also sold by many vendors; the most common ones being fruit, legumes, dairy products and boiled vegetables. Certainly, health advocates should support and encourage the sale of such items.

Table 2 Nutritional value of street foods, frequency of consumption and types of foods consumed

SF, street foods; %EI, percentage of energy intake.

In summary, energy intake from street foods in adults ranged from 13 %EI to 50 %EI and in children from 13 %EI to 40 %EI. Although the amounts differed from place to place, it should be borne in mind that even at the lowest values of the percentage of energy intake range, energy from street foods made a significant contribution to the diet. While the contribution of street foods to energy intake was reported frequently, much fewer data are available on macronutrients and micronutrients. The data available for Ca, Fe and micronutrients show that street foods tend to be high in Fe and vitamin A, but low in Ca and thiamin. No data were found on trans-fat, saturated fat and salt intakes.

Food groups

When discussing different food groups sold as street foods it needs to be recognized that urban dwellers have a more varied diet and consume more processed foods, animal protein and fats than rural dwellers⁽ Reference Levin, Ruel and Morris ^{18 )}. Urbanites also have greater access to processed foods and markets. Some studies presented findings on the types of food groups sold in street foods for different countries. In Haiti, for example, 146 different street foods were identified in Port-au-Prince of which cereals and grains accounted for 28·0 %, fruit for 18·5 %, and sugars and syrups for 16·4 %⁽ Reference Webb and Hyatt ^{10 )}. In Abeokuta, 50 % of meat and fish, 60 % of legumes and an estimated 42–66 % of all major food groups came from street foods⁽ Reference Oguntona and Kanye ^{12 ,} Reference Oguntona, Razaq and Tolulope ^{13 )}. In Nairobi, in low-SES areas, more than half (53 %) of the vendors sold foods of only one group⁽ Reference Mwangi, den Hartog A and Mwadime ^{20 )}. Overall 36 % sold only carbohydrate products in Kumba, Cameroon⁽ Reference Acho-Chi ^{31 )}. Furthermore, the type of foods sold differed from area to area. For example, both vendor-prepared foods and ready processed foods were sold in a low-income area in Tunisia, while in an industrial area many vendors also sold foods that needed no preparation⁽ Reference Neffati, Ridha and Kolsteren ^{32 )}.

Frequency of street food consumption

Frequency of street food consumption varied widely between countries and areas (Table 2). In Mali, for example, street foods were consumed on a daily basis⁽ Reference Ag Bendech, Chauliac and Malvy ^{15 –} Reference Ag Bendech, Chauliac and Gerbouin-Rerolle ^{17 )}. Similarly, a study in Nigeria indicated that street foods provided more than 60 % of daily food intake⁽ Reference Oguntona and Tella ^{19 )}, while in urban Kenya the intake appeared to be less with 53–78 % of households consuming street foods at least once weekly⁽ Reference Van ‘t Riet, den Hartog and Mwangi ^{21 ,} Reference Van ‘t Riet, den Hartog and Mwangi ^{22 )}; however, street food consumption was high in rural areas of Kenya, with schoolchildren eating street foods about twice daily⁽ Reference Gewa, Murphy and Neumann ^{25 )}. A national study in South Africa reported that Africans were the most common consumers of street foods with 19 % consuming them at least twice weekly⁽ Reference Steyn and Labadarios ^{27 ,} Reference Steyn, Labadarios and Nel ^{28 )}.

Type of food sold on the streets

It may be impossible to calculate the number of different street foods sold globally. Table 2 provides some idea of the wide variety of street foods available in different countries. Not only do they differ from country to country, but also by city and by vendors themselves. It appears that the bulk of items are based on traditional and cultural foods although foods processed by large-scale manufacturers are also an important category of items sold, particularly with regard to snack foods such as candies, chocolates, biscuits and crisps. Generally, vendors sell more than one kind of product although some specialize in one type only, such as bread with different fillings⁽ Reference Draper ^{1 )} or different soft drinks. Street foods can be grouped in various ways: by meal (with various constituents); by single food items or beverages; by level of processing; and by method of cooking (e.g. fried, boiled, baked, steamed or raw)⁽ Reference Draper ^{1 )}.

Association of socio-economic status with street food consumption

It appears that food vendors target their range of food items to the SES of the area and the income level of the consumers (Table 3). For example, vendors sold more foods from different food groups in the working class area (53 %EI) than in the slum area of Nairobi (43 %EI)⁽ Reference Mwangi, den Hartog A and Mwadime ^{20 )}. In Mali, 95·4 % of children ate street foods at least once daily⁽ Reference Ag Bendech, Chauliac and Malvy ^{15 –} Reference Ag Bendech, Chauliac and Gerbouin-Rerolle ^{17 )}. The practice was highest in poorest and middle-SES groups⁽ Reference Levin, Ruel and Morris ^{18 –} Reference Mwangi, den Hartog A and Mwadime ^{20 )}; however, expenditure on street foods was highest in middle- and high-SES areas⁽ Reference Oguntona and Tella ^{19 )}. A national study on street foods in South Africa⁽ Reference Steyn and Labadarios ^{27 ,} Reference Steyn, Labadarios and Nel ^{28 )} indicated that moderate street food intake was highest in the middle SES category (29·7 %) and in the frequent eaters (at least twice weekly) it was 14·2 %. These data suggest that street foods are sold in all SES areas although the type of items may vary according to the disposable income of the consumers.

Table 3 Association of street food consumption with socio-economic status

SF, street foods; SES, socio-economic status; %EI, percentage of energy intake.

Advantages of the street food trade

Street foods are usually economical, socially and culturally appropriate food items or meals. With many adults working long hours the use of street foods saves time in preparation of foods. Furthermore, street foods are usually available in small quantities and ingredients do not have to be purchased from the market for home food preparation. Fuel costs are generally high in developing countries and buying street foods saves not only on labour time but also on fuel costs. Furthermore, poor people often do not have adequate cooking facilities and space, hence purchasing ready-to-eat food is an advantage⁽ Reference Mwangi, den Hartog and Foeken ^{4 ,} Reference Drabo, Toe and Savadogo ^{33 )}.

Another important advantage of the street food trade is that of income generation. Many illiterate and unemployed people, frequently women, find this a simple way to earn some money with little capital investment required. According to Dawson and Canet⁽ Reference Dawson and Canet ^{34 )}, among lower-income groups in many developing countries 50–70 % of household earnings are spent on street foods. This also applies to schoolchildren, who may be given money to buy breakfast and/or lunch instead of being given cooked food or snacks⁽ Reference Ag Bendech, Chauliac and Gerbouin-Rerolle ^{17 )}. Hence street foods also potentially contribute significantly to the diet of schoolchildren. Because of their widespread use, Draper⁽ Reference Draper ^{1 )} further recommends studying the feasibility of using street foods as vehicles for micronutrient fortification.

It appears that cooked foods (cuisines, in particular) have become tourist attractions in certain countries and are often hailed as being authentic and unique dimensions of culture, lifestyle and even heritage⁽ Reference Henderson, Si Yun and Poon ^{35 )}. For example, in a study in Singapore, 65 % of tourists agreed that street food centres had an appealing uniqueness and cultural significance⁽ Reference Henderson, Si Yun and Poon ^{35 )}. Moreover, 58 % of tourists indicated that street food centres/areas were their means of learning about Singapore heritage.

Negative connotations of the street food trade

Unfortunately the use of street foods has many negative connotations with regard to hygienic and safety issues, and in many countries this trade is not regulated, which means that bacterial contamination of such foods is of concern to many who buy these products. Numerous studies have documented these effects and certainly one would need to pay attention to addressing these issues before encouraging the sale of street foods⁽ Reference Draper ^{1 )}.

An important concern that requires cognition when discussing street foods in developing countries is the westernization of diet, which has led to increased intakes of saturated fat, trans-fat, sugar and salt⁽ Reference Nago, Lachat and Huybregts ^{3 ,} Reference Macias, Pita and Basabe ^{36 )}. Women studied in Burkina Faso⁽ Reference Becquey and Martin-Prevel ^{26 )} showed some of these trends since food bought outside the home by them accounted for 52 % of fat intake and 72 % of sugar intake. In Tunisia more than 70 % of children studied used 75 % of their pocket money to buy street foods. Items bought most frequently were candy (27·2 %), pastries (23·9 %), sandwiches (23·9 %), sunflower seeds and peanuts (21·0 %), and either chocolate, pizza or cheese (20·0 %)⁽ Reference Neffati, Ridha and Kolsteren ^{32 )}. The largest proportion of money was spent on candy, pastries and sandwiches. The main motivation for buying street foods was to replace a meal at home. With the exception of peanuts and sunflower seeds, the other items did not reflect a traditional Tunisian diet and are typical examples of ‘western foods’.