The increase in consumption of meals outside the home is a worldwide trend and is related to behaviors and food choices conditioned to several factors, such as changes in lifestyle, work routine, expansion of delivery services, era of connectivity and the use of new information technologies that are changing the way we consume, distribute and produce food. However, this practice may be related to adverse health outcomes. In this context, this article aimed to investigate, in the existing literature, evidence on the possibility of healthy eating outside the home with a focus on the nutritional quality of food and the different types of services offered. There were indications that fast food restaurants are related to the poor quality of the diet because they contain higher energy content, saturated fat, sodium, sugary drinks and involve smaller portions of dairy products, vegetables and fruits, although they are evolving with the supply of healthier options on the menu. A la carte services, buffet, canteen, restaurants by weight and self-service are likely to encourage healthy and environmentally sustainable consumption in meals away from home. However, the role of the nutritionist stands out both in providing healthy preparations and in promoting food and nutrition education programs

The Law of the National Food and Nutritional Security System (SISAN) consists of the right of all individuals to healthy, quality, and sufficient food, aiming to expand conditions for regular and permanent access to food, mainly derived from traditional and family agriculture, processing, industrialization, and commercialization (BRAZIL, 2006). Faced with globalization and industrial development, which occurred in the mid-twentieth century, there was a change in the global scenario that influenced economic, social, and food factors. The job market accelerated the population's routine, leading to increased acquisition of processed products and eating outside the home (SOUZA, 2017).

According to the Brazilian Association of Bars and Restaurants (ABRASEL), Brazilians are eating out more (ABRASEL, 2019). Data from the Household Budget Survey (POF) 2017-2018, released by the Brazilian Institute of Geography and Statistics (IBGE), revealed that families spent, on average, R$ 658.23 per month on food, with 67.2% (R$ 442.27) on food consumed at home and the remaining 32.8% (R$ 215.96) on food in restaurants, bars, and snack bars. Over a decade, the proportion of resources allocated to eating out increased from 31.1% (POF, 2008-2009) to 32.8% (POF, 2017- 2018). Among families living in urban areas, eating out increased from 33.1% to 33.9% over the same period, with the greatest jump occurring among families in rural areas, from 17.5% to 24.0% 

Literature review study in which the databases Lilacs, Ibecs, Medline, and PubMed were consulted, through which scientific articles published in English and Portuguese between 2011 and 2020 were selected. These articles conducted studies involving the  (IBGE, 2019).

Given the increase in food consumption outside the home, the Brazilian Association of Food Industry (ABIA) revealed that, in 2018, sales in the food service channel (food prepared outside the home) expanded by 4.8% compared to the previous year. The main factors driving this market growth include changes in the population's lifestyle towards more convenient and practical eating, a higher number of women working outside the home, rapid expansion of delivery services, the era of connectivity, and the use of new information technologies altering the way food is consumed, distributed, and produced, among others (ABIA, 2019). Thus, for the coming years, according to the Brazilian Association of Bakery and Confectionery Industry (ABIP), the food service market will experience further growth due to increased population density, the busy lifestyle of large cities, the search for new gastronomic experiences, and for services and products that are differentiated, such as artisanal, organic, fresh foods, and those that cater to dietary restrictions (ABIP, 2018).

This study aimed to investigate, in existing literature, evidence of the possibility of achieving healthy eating outside the home, focusing on the nutritional quality of foods and the different types of services offered.

investigation of the possibility of having a healthy diet outside the home.

The descriptors used for searching articles in the databases were as follows: in Portuguese, "comida saudável" (healthy food) and "restaurantes" (restaurants), and in English, the term "healthy eating away from home" was used. Although this term is not an indexed descriptor in Decs (Health Sciences Descriptors), due to its importance for the search, it was adopted as a keyword.

Using the aforementioned descriptors, starting from the year 2011, four articles were found in Lilacs, two in Ibecs, two in Medline, and 103 articles in PubMed, totaling 111 studies. However, only six were related to the objectives of this study. The initial analysis of the articles was conducted based on the title and then on the abstract. Additionally, 33 references were included due to their relevance to the study.

The characteristics of the environments where people acquire or consume food exert a powerful influence on eating behavior (BIANCHI et al., 2018). Thus, the habit of eating out has been associated with higher energy intake (ROBINSON et al., 2018), lower consumption of vegetables (TODD; MANCINO; LIN, 2010), as well as larger portions of meat (SEBURG; CRANE; SHERWOOD, 2017), and for these reasons, it constitutes a risk factor for less healthy food choices and increased body weight (ALLMAN-FARINELLI et al., 2019). It is presumed that fast food, in particular, is associated with poorer diet quality and adverse health outcomes, such as the onset of non-communicable chronic diseases, due to their higher energy content, saturated fat, sodium (REZNAR et al., 2019; GRUNSEIT et al., 2019), being accompanied by sugary drinks, and involving smaller portions of dairy, vegetables, and fruits (POTI; DUFFEY; POPKIN, 2014).

In the study by Watts et al. (2017), in Canada, purchasing snacks was associated with lower diet quality among adolescents seeking treatment for obesity, and they suggested that improving the quality of food obtained outside the home could contribute to healthier eating practices. However, young adults represent a more likely age group to eat out and are also heavy consumers of sugary drinks and snacks (SEGUIN et al., 2016). For many, eating out was seen as a special occasion, so healthy foods were not a priority, and despite understanding the health consequences of low-quality diets, this was not an immediate concern (ALLMAN-FARINELLI et al., 2019).

However, the concern for healthy eating is increasing and becoming more frequent in the population (CONSTANCIO et al., 2016; SOUKI et al., 2019). In view of this, environments outside the home are adapting to the clientele's profile and can play an important role by providing alternatives aimed at facilitating healthy and sustainable food choices for people (LORENZ; LANGEN, 2018). In fact, fast-food restaurants are evolving over time as they have begun to include healthier options, such as salads and modified versions of preparations, for example, baked instead of fried, to become healthier (PATETTA; PEDRAZA; POPKIN, 2019). 

Another way restaurants can contribute to healthier and more sustainable meals is by modifying portion sizes (HOLLANDS et al., 2015), as these have been shown to be an important factor in reducing calories in out-of-home eating (SCOURBOUTAKOS; L'ABBÉ, 2012). In four types of restaurants in the Netherlands, including à la carte service, buffet, canteen, and self-service with a counter concept, it was possible to reduce meat consumption and increase vegetable consumption while maintaining high customer satisfaction by reducing the portion size of meat and increasing the portion size of vegetables in the dishes offered, paying particular attention to the preparation and presentation of vegetables; thus providing a viable strategy to promote healthy and environmentally sustainable consumption in out-of-home meals (REINDERS et al., 2020).

However, even in these types of services, chefs may be reluctant to reduce the amount of meat because they are concerned that meals will be less valued and demanded by customers (RIIS, 2014). They may also hesitate to serve more vegetables, fearing that this may result in longer preparation times and waste (GLANZ et al., 2007). Additionally, there may be a lack of skill and training on how to serve healthier dishes among chefs (OBBAGY et al., 2011).

In contrast, in buffet-style restaurants, characterized by self-service or "by-weight" systems, a modality widely used in the Brazilian reality where diners choose what they wish to consume, paying based on the weight of the culinary preparations served on their plate, Santos et al. (2011) demonstrated that the variety of choices, the possibility of affordable prices, speed, and convenience offered in this type of service may represent an alternative for healthy eating outside the home. Furthermore, the possibility of waste in buffet- style restaurants, characterized by weight, would possibly be reduced since the price to be paid for the meal is determined by the weight of the customer's plate (SANTOS et al., 2011).

Nevertheless, Castro, Mattos, and Righi (2019) emphasize that the self-service restaurant model is ideal for the modern worker as it offers options for all types of people, such as vegetarians, vegans, those seeking healthier foods, or those who enjoy fried foods and still want to savor a great dessert. In these distribution systems, the diner individually decides what to consume, facing a diversity of hot and cold dishes presented on counters where the customer serves themselves, choosing from the various options offered, whose structure and importance are defined by the restaurant manager, differing from the family context where dietary decisions are largely delegated to the homemaker (POULAIN, 2004).

In the study by Patetta, Pedraza, and Popkin (2019), conducted in the United States, it was evidenced that restaurant food surpassed that served at home as the healthiest source of food, while the fast-food category remained the most detrimental. Gorgulho (2012), in assessing the relationship between eating out and the quality of the diet of residents of São Paulo, also observed that the nutritional quality of meals eaten at home needed improvement. Additionally, it was observed that individuals with low income emerge as high-risk groups for poor food quality (PATETTA; PEDRAZA; POPKIN, 2019), due to the relatively cheap prices of unhealthy foods and limited access of low-income individuals to healthy food sources (RICHARDSON et al., 2014).

At the popular restaurant located on the coast of Paraná, frequented mostly by people with low financial income, the main factors influencing the consumption decision-making process were low price, followed by food quality in relation to the availability of 

 healthy meals. However, the study observed that as education level increased and income decreased, the frequency of this consumer at the popular restaurant decreased (BORNANCIN; PINTO, 2018). In this sense, popular restaurants can represent a tool to reduce food and nutritional insecurity since they offer low-income populations healthy and low-cost food (ZANINI; SILVEIRA; SCHNEIDER, 2018). Therefore, it is emphasized that efforts to improve the nutritional quality of low-income individuals should aim at the accessibility of healthy foods in stores, restaurants, and fast-food sources to limit the disparity in nutritional quality among different economic strata (RICHARDSON et al., 2014).

It is worth noting that for nutritionally adequate meals to be provided in these types of restaurants, the role of the nutritionist is prominent. According to the Federal Council of Nutritionists (CFN), it is the responsibility of these professionals to plan and develop menus and coordinate the development of recipes and technical sheets (CFN 600/2018). In buffet-style restaurants, promoting health through such responsibilities is an even greater challenge since the diner is the one making the choices, which can be made inadequately. Thus, the role of the nutrition professional is highlighted both in providing healthy preparations and in promoting food and nutritional education programs.

The present study has allowed us to identify, in the existing literature, that currently, there is the possibility of having a healthy diet outside the home with nutritional quality across various service modalities offered. However, fast-food restaurants are still associated with poorer diet quality due to their higher energy content, saturated fat, sodium, sugary drinks, and smaller portions of dairy, vegetables, and fruits, despite evolving as they began to offer healthier options on the menu.

Considering the increasing consumption of meals outside the home and the complexity of factors involved in individuals' eating behaviors, it is considered important to create environments conducive to health, enabling access to healthy foods, with emphasis on the role of the nutritionist in ensuring the availability of healthy food options and promoting food and nutritional education programs. Thus, the presence of a nutritionist becomes important in different types of food service to provide credibility to meal balance and food handling hygiene practices.