Food for Soul—Older Immigrants’ Food Habits and Meal Preferences After Immigration: A Systematic Literature Review

There are few primary studies that focused on the older immigrants’ food habits and meal preferences after immigration and settlement in a new country. A comprehensive database search for literature was conducted in May 2021 and upgraded in September 2021. Ten databases (Medline (Ovid), EMBASE (Ovid), PsycInfo (Ovid), Cinahl (EBSCOhost), Food Science Source (EBSCOhost), SocIndex (EBSCOhost), Social Care Online, Applied Social Sciences Index & Abstracts (ASSIA), Web of Science and Google Scholar), were scanned for original, peer-reviewed papers published in English. The review was conducted and reported in accordance with the PRISMA 2020 guidelines and SWiM items. Out of 3069 records, 10 papers were included for thematic synthesis. A data synthesis across all studies resulted in three main findings: (i) the significance of food in maintaining cultural identity, (ii) the continuity of traditional food culture and (iii) adapting to the host country’s food culture. Although different forms of dietary acculturation occur throughout life, older immigrants often want to maintain their traditional food habits and meal preferences. For them, traditional eating habits offer comfort and security by serving as a means of identifying who they are and reminding them where they have come from. Public health and social services play an important role in providing cultural nutritional care to older immigrants; therefore, this issue should be carefully addressed by professionals and future research. Registration: The review protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) on 27 September 2022 with registration number CRD42022358235. Supplementary Information The online version contains supplementary material available at 10.1007/s10903-023-01571-5.


Introduction
Global population migration has changed the demographics of many countries leading to culturally diverse societies [1].In 2020, 281 million people resided in a country that was not their country of birth [2].The world's population is aging rapidly, and older adults compose a larger proportion of the world's population [3].Thus, the combination of migration and an ageing population are two major challenges that many countries face in the twenty-first century [4].World Health Organization [3] defines older people as persons who are over 60 years of age.Older immigrants are defined as people aged 60 years or older, who have moved away from their place of usual residence to live temporarily or permanently in a foreign country [2].Older people who receive healthcare services are facing challenges related to inadequate nutritional care and malnutrition [5].Nutritional challenges is also a concern among older immigrants; therefore, to deal with the challenges related to nutrition, it is important that healthcare professionals understand the nutritional needs of the ageing population, as well as their preferences and perceptions related to food.
Because of the differences in cultural, religious, and socioeconomic backgrounds, immigrants may have food habits and meal preferences other than those of the host population.This is particularly pertinent for those who are in vulnerable conditions, such as illness and frailty, where immigrants need assistance with food and meals from healthcare services [6].Results from a scoping review indicate that ethnic food consumption can have a positive impact on mental health among immigrants [7].Food is not only important for health and in physical sustenance, but it is also linked to an individual's personality, cultural identity, social practices, and religious beliefs, in addition to generating enjoyment and a supporting quality of life.Moreover, results from a previous study conducted among British Bangladeshis has shown that behaviors surrounding the preparation and consumption of ethnic foods are some of the most resilient aspects of a migrant culture [8].
After immigration and settlement in a new country, immigrants are exposed to the host country, resulting in physical, biological, political, economic, sociocultural and psychological changes [9].The process through which immigrants and their children are exposed to the values, behavioural norms and attitudes of the host society is defined as acculturation [10] (p.708).The acculturation process also includes food consumption [11], which is often called dietary acculturation.Dietary acculturation involves both the retention of certain dietary behaviours and incorporation of new foods and eating habits from the new country [12].The results from a study conducted by a Romanian research team revealed that the longer Romanian immigrants resided in Andalucía, Spain, the more they perceived changes in their food consumption habits, thus demonstrating a gradual adoption of Spanish foods [13].After acculturation has occurred, the most common feature is so-called 'bicultural food habits', indicating the consumption of traditional food or traditional meals while adding the host population's food and meals [12].
Although immigrant groups tend to adopt the food habits of the host country [12], the opportunity to have access to traditional food and preserve familiar meal patterns is deemed important [14].Food communicates history, memory, feelings, and social status [15].Moreover, food is a source of comfort in life [16] and central to all the processes needed to adapt to a host country [17].Meals are opportunities for socialisation and interaction, both of which are important for a person's identity and integrity [18].Although the meaning of meals and food has evolved across the stages of the life cycle, the eating habits of elderly individuals tend to be characterised by lifelong patterns of eating that have meaning and significance in their everyday lives [19].
During the ageing process, older immigrants may increasingly become more dependent on others to provide their meals.Traditionally, care for the elderly from minority groups was provided by family members [20].However, because of the socioeconomic transformations in the host countries and societies at large, family caregiving attitudes have changed, and family caregiving is now somewhat weaking [21].The responsibility of caring for older family members from immigrant groups, including the provision of nutritional care, has gradually been transferred to public healthcare services [21].Therefore, healthcare workers providing nutritional care need to be aware of the food habits and meal preferences of elderly from minority groups [22].Meals that are adequate from a nutritional perspective but fail to meet cultural, taste or religious preferences may be only partially eaten or not eaten at all, which again can have serious health consequences, particularly for vulnerable groups such as older immigrants.Although there are several studies exploring dietary changes after migration and settlement in a new country, there is a paucity of specific knowledge about food habits and meal preferences among older immigrants; therefore, more knowledge is needed.The aim of this systematic review is to identify and synthesise the research studies that address older immigrants' food habits and meal preferences after immigration and settlement in the host country.The present systematic review will therefore answer the following research question: 'What are the older immigrants' food habits and meal preferences after immigration and settlement in the host country?'.

Methods
The review protocol was registered in the International Prospective Register of Systematic Reviews (PROS-PERO) on 27 September 2022 with registration number CRD42022358235.
A systematic review of the literature with qualitative and quantitative study designs was conducted following the recommendations of the Preferred Reporting Items Systematic Review and Meta-Analysis guidelines (PRISMA) [23] and the synthesis without meta-analyses items (SWiM) [24] (Supplementary Files S1&S2).
As a systematic review, the present study does not need ethical approval according to the Norwegian Research Ethics Act.The studies included in the review had ethical approval or clear ethical statements.

Data Sources and Search Strategy
A comprehensive database search was conducted by three academic librarians during May 2021 and upgraded in September 2021.Three groups of relevant search terms ('Food', 'Immigrants', 'Older people') and their synonyms were used and combined using the Boolean operators AND and OR as per the example search strategy shown in Table 1.Search terms were applied consistently across nine databases, including Medline (Ovid), EMBASE (Ovid), Psy-cInfo (Ovid), CINAHL (EBSCOhost), Food Science Source (EBSCOhost), SocIndex (EBSCOhost), Social Care Online,  To ensure that relevant studies would not be missed, no publication date, country where the study was conducted and restrictions on the methodology were imposed.To locate additional studies, mail notifications were created in the databases.The reference lists of the identified studies were also screened to ensure that relevant research was not overlooked.

Eligibility Criteria
Peer-reviewed primary studies-regardless of methodology-that provided relevant information about the aim of the current review were eligible for inclusion.

Inclusion Criteria
-Studies reporting sociocultural aspects of the food habits/ meals/nutrition of older immigrants -Studies including and specifically present results from participants aged 65 years or older and who are defined as immigrants -Studies that present subgroups of results or specific statements from participants aged 65 years or older -Studies published in English -Studies published all over the world with no limit for publication year or ethnicity for the older immigrants

Search Outcomes and Study Selection
The references provided by the literature search were exported to EndNote library [25].After removing duplicates,  the references were transferred to Covidence literature screening software [26] for deduplication to allow for a streamlined review process and blinded double screening in all study phases.After the initial search, mail notifications about new articles were created.Additionally, reference lists of the received titles were screened.No studies from mail notifications or from reference lists met the inclusion criteria.
For study selection, studies were screened in three stages: (i) screening title, (ii) reading abstracts and (iii) reading fulltext articles and data extraction.In stage one (i), all authors independently screened a total of 3,069 titles for relevance to the review's aim.A total of 2,844 records were excluded because they were books, book chapters, conference papers, posters, editorials, PhD theses or protocols or did not meet inclusion criteria.In stage two (ii), the remaining 225 studies were equally distributed between reviewer pairs, with each reviewer pair screening an average of 90 titles and abstracts against the eligibility criteria.At this stage, 215 studies were further excluded.In the last stage (iii), all authors read the full text of the potentially relevant studies and then independently decided whether a study would proceed to data extraction.Discrepancies between reviewer pairs were resolved through discussion until a consensus had been reached or by involving all authors if the first ones failed to settle discrepancies.The search results and reasons for excluding studies are presented in the PRISMA flow diagram (Fig. 1), leaving 10 studies to be included in this review.

Quality Appraisal
The Mixed Methods Appraisal Tool (MMAT) [27] was employed as a checklist to critically evaluate the studies included in the review.Pairs of two reviewers conducted a quality appraisal of the studies.To avoid erroneous conclusions, uncertainties were solved by reviewers discussing them with each other until consensus was achieved.
The MMAT integrates the quality appraisal of different study designs, hence allowing for an assessment of the methodological quality of multiple methods of studies.The MMAT includes a total of 25 criteria and two screening questions and can appraise five different categories of study designs: (a) qualitative, (b) randomised controlled, (c) nonrandomised, (d) quantitative descriptive and (e) mixed methods.Each category has five core quality criteria rated as 'yes', 'no' or 'can't tell' (Table 2).

Data Extraction
A data extraction form was developed based on the aim of the review, including information about the study.The extracted data of the included studies covered the following: (a) author(s), year of publication and country where the study was conducted, (b) title, (c) aim and research design, (d) sample, (e) data collection methods and analysis, (f) findings/results and (g) conclusions.An overview of the studies' characteristics is presented in Table 3.

Data Synthesis
A narrative summary was undertaken for the qualitative studies [28].The data were summarised under the same categories.Although two of the studies [29,30] also present findings generated from interviewing healthcare professionals and/or family members, only data generated from older immigrants were extracted, analysed, and included in the synthesis.
Because of the heterogeneity in study designs, the methods for data collection and outcomes of the quantitative studies included in the review, a meta-analysis was not feasible.Therefore, to integrate and analyse the information, a narrative synthesis which adopts a textual approach to summarise the findings of systematic reviews, was performed for these three quantitative studies [31].

Study Characteristics
The search for empirical studies resulted in a total of 10 studies: seven qualitative [9,29,30,[32][33][34][35] and three quantitative, nonrandomised [36][37][38].The qualitative studies included in the current review were of good quality, met the MMAT's assessment criteria and were found to provide sufficient information needed to determine their methodological quality.The quantitative studies described no intervention or measurement; therefore, we could not assess if the intervention was administered (exposure occurred) as intended.

Year of Publication and Country of Origin
The period of publication of the included studies was between 1991 and 2022, peaking at two articles published in 2019.The studies originated from Australia (1), Brazil (1), Canada (2), The Netherlands (1), Sweden (1), the UK (2) and the US (2).Most of the studies were conducted in Canada, the UK, and the US.

Aim and Research Design
The aim of the qualitative studies included in the review was to explore older immigrants' food habits and meal preferences after immigration, how and why diets changed after immigration and the influence of migration on dietary practices and the process of dietary acculturation [33][34][35].
Two studies explored the meal context and food offered in Canadian and US public nursing homes with respect to firstgeneration immigrant residents [29,30].One study had a longitudinal qualitative design [32], two had ethnographic designs [9,29], three had qualitative descriptive designs [30,33,34], and one had a qualitative explorative design [35].Among the quantitative studies, one had a case study design [36] while the other two had a cross-sectional design [37,38].One study additionally aimed to obtain insights into the possible dietary differences between older Iranian immigrants living in Sweden and older Iranians living in Teheran, Iran [37].

Sample
Overall, this review presented the perspectives or experiences of 488 participants.The sample in all studies consisted of participants aged 65 and older.
The sample in the qualitative studies consisted of 209 participants (N = 102 women and N = 107 men).The sample in one of the studies [29] consisted of nursing home residents (N = 26), family members (N = 24) and frontline care staff (N = 51), but information about the gender of the participants was provided only for the nursing home residents (N = 13 females; N = 13 males).Besides older immigrants, three qualitative studies also included family members from immigrant families [9,29,30] and healthcare personnel [29,30].A total of 279 respondents, both women (N = 182) and men (N = 97), participated in the quantitative studies.
Except for one study [29] that referred to study participants as 'first-generation immigrant residents' without giving further information about their nationality, the rest of the studies provided complete demographic information about the sample, that is, age, gender, ethnicity, marital status and living conditions, education level, faith/religion, length of residence in the host country, dietary patterns and eating habits before and after immigration.Only two studies [9,38] provided information about the older immigrants' status as refugees at the time of immigration.
Eight studies included only one cultural group, as reported by nationality, for example, Iranians [37], Ghanaians [35], Vietnamese [38], Syrians [9], Hindustani [36] or Chinese [30,33,34].One study included more than one ethnic or national group, referring to the participants as ethnically diverse older adults who identified themselves as Africans, Indians, Pakistani, Bangladeshi or Caribbean [32].In another study, the participants were referred as 'non-Quebec born residents, all non-native French or English speakers from a wide range of sociocultural and geographic horizons' [29] (p.227), providing no further information about their migration history or socioeconomic and cultural characteristics.Although most of the studies included home-dwelling older immigrants, two studies were conducted within the nursing home context, including nursing home residents [29,30].

Data Collection and Data Analysis
Among the qualitative studies, four studies employed only in-depth individual interviews using a semi-structured interview guide as the data collection method [32][33][34][35].One study used focus group interviews with six participants on average per group [29].Three studies also used observation in addition to interviewing during data collection [9,29,30].Thematic analysis [9,29,30,[33][34][35] or content analysis [32] were used to analyse the data generated from interviews, focus groups and observations.
Quantitative studies [36][37][38] used surveys to collect data.One study also used a 24-h recall dietary recall procedure, here with open-ended questions [38].Data were analysed using descriptive statistics.

Summary of the Findings
Twelve categories underpinned by 22 findings were metaaggregated into three synthetised findings: (i) the significance of food in maintaining cultural identity; (ii) the continuity of traditional food culture; and (iii) adapting to the host country's food culture.The synthetised findings, categories and extracted findings are presented in Table 4.

The Significance of Food in Maintaining Cultural Identity
The results of the included studies revealed that most of the immigrants, especially the first-generation immigrants, emphasised strong connections between their cultural food and ethnic identity.The importance of maintaining cultural identity through various cultural, traditional food practices, such as eating certain types of food and the ways food was prepared, was emphasised in several studies [30,32,33,35,38].Preparing and eating 'our food' or 'African foods' [35] or 'Chinese food' [30] was important for maintaining 'identity', 'our culture' as well as a 'legacy' that should be passed on to the next generation [33].For Asians, rice and tea served at almost every meal were staple foods for all ages [30,38].Moreover, keeping food routines and traditions, such as going every week to dim sum (restaurants serving traditional Chinese cuisine of bite-sized food served in small steamer baskets) and meeting other Chinese families, supported family' values, thus honouring identity in Chinese culture [33] Connections between food and identity hinged upon memories evoked through sensory engagement with ethnic food, thus linking ethnic food with memories of home [9], or memories of childhood, as echoed in another study [38].In addition, eating and retaining traditional food practices was found to uphold traditional individual and family identities and roles [33]; for example, across all cultures, women tend to hold significant food-related roles associated with providing food for their families as wives and mothers.

The Continuity of Traditional Food Culture
Overall, there were several reasons why certain aspects of diet did not change after immigration.One of them referred to the availability of and accessibility to ethnic food stores in the host country over the past few decades, thus enabling the continuity of original food culture [32,35,36].However, the review also indicated that if a known food was not available, the participants searched in the new food culture for foods similar to those from their original food culture or used the same recipe and ingredients as they used in their country of origin to maintain their cultural eating habits [9].On the other hand, being flexible and substituting or omitting ingredients in traditional Chinese recipes, for example, when they were not available in the host country was another strategy to perceive the diet as not changing after immigration [34].Nevertheless, although many modifications in food The significance of food in maintaining cultural identity Traditional food preferences [35,38] Diet and nutrition beliefs [30,38] Food as an expression of culture, identity, and relationships [32,33] Keeping culture with food ways [33] Eating known and most familiar staple foods for all ages (rice for Asians) Using food to preserve traditional culture Eating 'healthier' because immigrants can access the foods they prefer and value Traditional food satiates for longer Continuity in food eating to uphold traditional individual and family identities Eating traditional food is part of their 'identity', 'heritage' or 'culture' Sharing food and eating together (dim sum in Chinese culture) Food linked to one's identity, with mealtimes helping create a sense of belonging Food and meal practices mean more than nutrition and are dependent on social context for their meaning Food connects older immigrants to the past (brings good memories for those living with dementia) Recognisable food that represents something good to 'us' or 'for me' The continuity of traditional food culture Absence of dietary changes during food preparation [9] Flexibility and recipe modification [34] Availability of and access to traditional food [32,35] Flavour -the driver of food choice [29,34,35] Food shopping practice [36,38] Accessibility and affordability to diverse traditional foods help immigrants feel comfortable When possible, using the same recipe and ingredients as used in their country Preferring food with taste (diversity in seasoning, cooking techniques and sauces using distinctive ingredients) instead of host country foods Being content with the availability of traditional food products (exotic fresh fruits and vegetables, fish, etc.) in ethnic shops or supermarkets Adapting to the host country's food culture The length of residence in the host country and immigrants' age when arriving in the host country [36] Embracing new foods and new mealtime routines [9,34,[36][37][38] The longer they live in the host country, the easier it is to adopt food products specific to the host country Younger immigrants change their food consumption after migration No access to traditional food in nearby food shops Changes in food habits because of a new environment (i.e., moving to a nursing home -institutional practices) Modified dietary habits to cope with changes reflecting economic and living conditions in the host country Changes in family mealtime routines because of lifestyle, work schedule, means of transportation or housing Changes in the way some foods are eaten (a phenomenon seen among children/younger) preparation occurred, some preparations could not be modified to maintain the original taste and flavour [9].Another reason for continuing to eat traditional food was related to personal taste preferences, such as preferring spicy ingredients [35].The studies also revealed that immigrants of older age were more likely to maintain their well-established eating habits, which remained similar to those they had when they lived in their country of origin [34,38].Although old age and different physical conditions and cognitive impairment lead to older immigrants moving to a nursing home, food preferences remained the same, with the older immigrants expecting to eat food inspired by their cuisine from their country of origin and retain a premigration style of eating [29,30,33].
Familiarity with cooking methods, especially within the Chinese food culture [30,34], was important for the continuity of preparing and eating ethnic foods.However, the findings revealed that immigrants' personal health beliefs and habits were important drivers to continue preparing and eating foods from their country of origin.For older Chinese immigrants, drinking hot instead of cold water [34], was a habit that was difficult to change.For older Muslims, continuing to eat halal meat, in accordance with Islamic law [9], was also important for keeping eating traditions alive.Moreover, believing that preparing and eating traditional foods from the country of origin was healthier than eating traditional foods from the host country [35] was another reason contributing to the continuity of the original food culture.

Adapting to the Host Country's Food Culture
Although the findings revealed that keeping traditional foods was important for immigrants' identity and their legacy, adopting some elements from the host country's food culture was also observed [9,35,36].When confronted with a new environment and differences in the availability of food in the host country, several immigrants needed to adapt and change their eating habits.The studies also revealed that older immigrants partially or totally adopted the foods and eating habits from the host country [9,35,37].Most of the changes occurred because of different routines and lifestyles they had in the host country, such as a busy work schedule, means of transportation, housing and family income [9] or because they did not have the necessary time to prepare the meals knowing that the preparation of varied dishes takes time [9,36].Another reason that food and eating habits changed, thus leading to dietary acculturation, was related to the perception that foods from the host country were perceived as healthier than foods eaten in their country of origin [37].
Changes in food and eating habits after immigration were also related to the immigrants' age at the time of immigration.Those studies providing data on both the older and new generations showed that younger immigrants more easily adopted food products and food preparation specific to the host country compared with older immigrants [9].Although the first-generation immigrants still prepared and are foods from their country of origin [33,34], the second-generation has gradually changed the foods and eating habits specific to the host country, eating original foods from their country of origin only occasionally and in contexts such as family visits or celebrations [35].
Another change that occurred was related to the duration and purpose of their stay in the host country-the longer the period that the immigrants had been residing in the host country, the easier they were able to change their food consumption habits [36].
Although the changes in food preparation and eating habits after immigration were, for most immigrants, voluntary choices, the findings from two studies [29,30] indicated that growing old in the host country and moving to a nursing home led to involuntary changes in food and eating habits that were mandatory because of institutional practices.

Discussion
In the current literature review, we identified and synthesised 10 studies addressing older immigrants' food habits and meal preferences after immigration and settlement in the host country.Our review has revealed that preparing and eating ethnic foods is an important part of everyday eating practices.For older immigrants, food and mealtimes were strongly linked to cultural and ethnic identities.Ethnic food was valued as an important bond connecting them to their country of origin.Moreover, preparing and eating ethnic foods created nostalgia for their country of origin, hence becoming part of remembering their past and acknowledging their heritage, thus providing a sense of belonging.
Maintaining cultural identity through the preparation and eating of ethnic food appeared to be more important to first-generation immigrants, which was especially true for women who had significant food-related roles in earlier life and was associated with providing food for their families as wives and mothers [33].These feelings were echoed in a study on the meaning of food and food preparation for Goan women in Toronto, Canada, and the role of food in creating and maintaining distinctly gendered ethnic identities [39], revealing that among other things, the power of food and foodwork in transmitting ethnic identity and the opportunity to draw family and community together, thus maintaining collective solidarity and identity.As also pointed out in an early study [40], because of the strong connection between food and identity, immigrants tend to conserve their eating habits.For them, food is one of the remaining bonds with the country of origin and a strong and meaningful component of their identity, being a prominent feature for elderly Vietnamese [38] and Chinese [33] living overseas.
Our review also found that identity is preserved through food practices and sharing [32].Chinese immigrants displayed their ethnic identities and reinforced their bonds to others who claimed the same heritage through the tangible medium of food.By sharing foods that they perceived to be traditional with other Chinese, they were reinforcing their common bond, even in a diaspora [33].These findings were similar to the findings presented in a study conducted among Barbadian immigrants in Atlanta, US, showing that Barbadians consciously deployed conspicuously Barbadian foods to signify their ethnic and national identity, both in situations where they were demonstrating solidarity with the Barbadian community, as well as to distinguish themselves as distinctly Caribbean in mixed American settings [41].
For older immigrants living in a nursing home, when the institutional food did not meet the residents' characteristics in terms of immigrant background and key elements of their cuisine, particularly seasoning and cooking techniques, family and friends chose to bring in home-cooked food that the resident appreciated and ate with gusto [29], thus honouring individual and family identity, which was special for those living with dementia [33].Moreover, serving 'recognisable' dishes brought by family members has been shown to allow older immigrants living in nursing homes to maintain and reaffirm their ethnic identities, especially for those living with dementia.The idea that traditional food strengthens the feelings of belonging, identity and heritage, thus helping persons with dementia hold on to and reinforce their cultural identity, was also supported by the findings presented in a Norwegian study revealing that familiar tastes and smells awoke pleasant memories in people with dementia and boosted their sense of well-being, identity and belonging, even producing words in those who usually did not speak [42].Moreover, food could bring back memories of childhood that reflected the usual practices and traditions that continue to influence current preferences.
The results from a recently conducted scoping review [18], showed that immigrants experienced that there was an overall abundance of food in the host country, with traditional foods being always available, not just seasonally as the immigrants were used to.The influx of ethnic minority corner shops and supermarkets in communities and larger cities, making available fruits, vegetables and spices, reinforced continuity of traditional food habits and meal preferences.This accessibility and affordability of traditional foods contributed to the continuity of the traditional food culture in older immigrants, which is in line with findings from our review [32,35,36] The importance of spices as markers for the smell and flavour of food, thus influencing food choices, emerged in several qualitative studies [9,29,34,35].This idea was supported by findings from other studies [14,43], suggesting that spicy food preparation was more valued and essential for older immigrants to preserve the original food culture after immigration and could not be replaced by commercially available food items.Our review has also shown that first-generation immigrants attempted to preserve food habits perceived as being of their country of origin, including spiciness in food [9,34,35].This was the most visible in the studies with a quantitative design where food preferences and type of foods eaten before and after immigration were displayed and compared with the majority population from the host country [36,38] or with the same ethnic group living in their country of origin, showing noticeable differences in food habits and meal preferences between older immigrants living in the host country and those living in their country of origin [37].
Sometimes, to preserve food habits and meal preferences, flexibility, and recipe modification were needed [34].Moreover, unfamiliar ingredients were adapted to preserve known food taste by adding spices [9].Flavours and distinct tastes are the strongest characteristics of traditional food [44]; therefore, our review indicates that, to preserve traditional familial food, older Chinese immigrants used mealtime as learning opportunities to teach younger generations cultural and traditional principles of food practices [33].
Although the significance of eating traditional food in maintaining older immigrants' cultural identity was emphasised, similar to findings from another systematic review [45], our review has revealed a process of change in food habits and meal preferences among older immigrants [36].Some of these changes occurred because of the older immigrants' perceptions of the host country's foods being healthier than their own traditional food [37].Because of altered routines and lifestyles with a busy work schedule and lack of time to prepare traditional foods [9,35], food changes were unavoidable.Other changes occurred involuntarily because of the process of ageism and altered sense of taste affecting their usual food habits, hence avoiding certain cultural spicy foods [30,33].For older immigrants living in nursing homes, the lack of culturally recognisable mealtimes contributed to altering their food habits [30].Moreover, changes in their food habits consisted not only of adopting different foods from the host country or adapting to new food flavours, but also of changing the number of meals they consumed in the day, usually skipping breakfast and/or lunch [9,34,37].However, eating traditional foods became a feature that occurred only on occasions such as family visits or feasts [35].
Accessibility and availability of ethnic food shops contributed to immigrants who migrated to the Western parts of the world in the last decade not perceiving challenges with maintaining their cultural food habits and meal preferences.In contrast, because of a lack of availability and accessibility to traditional foods, immigrants who migrated in the early 1970-1980s and grew old in the host country had to adopt certain foods [35] and dietary patterns [36,37].This contradicts the findings from a previous study [46], stating that, in the UK, the older generations of South Asians were less likely to change their food habits since they were more segregated from the majority population, thus continuing to eat traditional foods.This supports Kocktürk-Runefors' [47] theory suggesting that staple foods are the last to change following the postimmigration period.In contrast, younger generations of South Asians were found to be more likely to change their food habits and meal preferences by including English foods in their daily meals [46].These findings are in line with the findings from our review, where the younger generation accepted the host country's foods easier than the older generation from the same family [9].However, our review suggests that not only did the younger generation adopt the host country's foods, but for several reasons, older immigrants living in the host country did as well [34][35][36][37].For example, Chinese immigrants have often adopted a bicultural eating pattern, appearing to be caught at the intersection of East and West food cultures [34] and, thus, preserving elements from their Chinese culture and adopting some elements from the host country.This contrasts the findings from a previous study reporting that Chinese immigrants minimally changed their food habits, even as time spent living in the UK increased [48].
An important factor influencing the adoption of new foods was the age of immigrants at the time of immigration [36].Our review revealed that the older immigrants were at the time of immigration, the more difficult it was for them to change their food habits and be open to dietary acculturation.However, according to Cleveland et al. [49], acculturation is a complex process based on assimilation of the new culture (majority, the host) and the preservation and promotion of the culture of origin (minority), here further referring to Berry's [11] four patterns of acculturation: integration, separation, assimilation and marginalisation, where integration is the most common applied pattern-adopting the new culture and, at the same time, cultivating their culture of origin.This supports the findings from our review.
The length of residence in the host country was found to influence the degree to which immigrants adopted the host country's food habits.As our review suggested, the longer the stay, the easier it was for immigrants to adopt the host country's food habits and meal preferences; these findings are supported by the results from a study conducted among Romanians living in Andalusia, Spain [13].
Finally, when people immigrate and settle dawn in a new country, in their 'migrant suitcase' they not only bring their food with them, but also their representations and ideals of good food [43].Therefore, for older immigrants, eating 'food from home' can reconnect them with a sense of home, hence contributing to improving their quality of life in the host country.

Strengths and Limitations
To the best of our knowledge, this is the first review to present older immigrants' experiences with food habits and meal preferences after immigration and settlement in the host country.We sought studies that included diverse groups of immigrants with different designs and methods of data collection.Several studies included Chinese immigrants in Australia, Canada, the UK, and the US -countries wellknown for their increased level of immigration [50,51], hence to some degree reducing the transferability of the findings.
The included studies revealed older immigrants' experiences with food habits and meal preferences of both men and women from different ethnic groups belonging to several countries around the world, hence increasing the diversity with respect to ethnicity, gender and age.The participants in the included studies were home-dwelling older immigrants, but also those living in nursing homes.Because of the paucity of research focusing on older immigrants' food habits and meal preferences, we also included studies presenting subgroups of results or specific statements from participants aged 65 years or older.In some studies, the sample was also comprised of family caregivers and/or healthcare personnel.To avoid bias during the data synthesis, only data generated from the participants defined as older immigrants were analysed and further synthesised.Statements from family caregivers or healthcare personnel were not included in the synthesis.
We are aware that, because of the search strategy, some relevant literature may have been missed, though we did not limit the period of published research to a certain period.Because of the aim of the review, we have not mentioned the problem of a relatively high prevalence of noncommunicable diseases, such as diabetes, heart diseases or obesity, among older immigrants.Major barriers to healthy eating among older immigrants included lack of nutrition knowledge, families' preferences, cultural values, religious dietary proscriptions, financial constraints and low availability of food quality.These issues require further research.

Implications for Research and Practice
The knowledge from the current review has several implications for health and social services that should be considered.An ageing immigrant population will gradually be challenged with difficulties in coping with their food and nutrition, besides potential other health challenges; therefore, one may wonder who will take care of these individuals when they face these challenges.With family ties becoming loser and attitudes towards family caregiving constantly changing [21], public health and social services play an important role in providing adequate cultural nutritional care to older immigrants.Healthcare personnel should be aware of the food and eating habits of older immigrants.It is important that healthcare personnel have competence and opportunities to meet the needs of culturally appropriate food habits of older immigrants.Not acknowledging older immigrants' food habits and meal preferences could be a source of stress for this population when they are staying in a hospital or nursing home.Therefore, this issue should be carefully addressed by healthcare and social services and in future research.

Conclusions
Although there is a broad range of literature on food, immigrants and migration, this topic has not been fully investigated regarding older immigrants.There is a paucity of research focusing on older immigrants' food habits and meal preferences in the postimmigration period and the role food plays in shaping a sense of belonging among this group.However, our review revealed that older immigrants, regardless of being newly arrived or belonging to those who aged in the host country, have different food habits and meal preferences compared with the majority population in the host country.Depending on several factors, such as availability and accessibility of ethnic food shops, the age immigrants came to the host country, the length of their stay in the host country and alterations of their lifestyle, different forms of dietary acculturation exist.Despite these differences, our review has revealed that older immigrants wish to maintain their traditional food habits and meal preferences.For them, although they adopted some culinary elements from the host country, eating traditional food contributed to maintaining their cultural identity and to the continuity of traditional food culture.
Healthcare personnel should make efforts to target food literacy skills in older immigrants and encourage them to try new foods and eat healthier.Finally, understanding older immigrants' food habits and meal preferences helps health and social services ensure culturally appropriate nutritional care, thus optimising their health.

Table 1
Examples of literature search in databases Database: Ovid MEDLINE(R) and Epub Ahead of Print, In-Process, In-Data-Review & Other Non-Indexed Citations and Daily 1946 to May 11, * or eat* or diet* or nutrit* or meal* or cooking or dining) OR AB ( food* or eat* or diet* or nutrit* or meal* or cooking or dining) OR KW ( food* or eat* or diet* or nutrit* or meal* or cooking or dining) OR SU ( food* or eat* or diet* or nutrit* or meal* or cooking or dining) S7 DE "IMMIGRANTS" OR DE "IMMIGRANT men" OR DE "OLDER immigrants" OR DE "PERMANENT residents (Immigrants)" OR DE "UNDOCUMENTED immigrants" OR DE "WOMEN immigrants" OR DE "ASSIMILATION of immigrants" OR DE "EMIGRATION & immigration" OR DE "REFUGEES" 2,949 S8 DE "MINORITIES" OR DE "ATTITUDES of ethnic groups" OR DE "MINORITY older people" OR DE "MINORITY women" OR DE "RACIAL minorities" OR DE "ETHNICITY" OR DE "RACE" * or migrant* or ethnic* or racial* or minorit* or refugee* or "non western*") OR AB ( immigra* or migrant* or ethnic* or racial* or minorit* or refugee* or "non western*") OR KW ( immigra* or migrant* or ethnic* or racial* or minorit* or refugee* or "non western*") OR SU ( immigra* or migrant* or ethnic* or racial* or minorit* or refugee* or ""OLD-old" OR DE "OLDER men" OR DE "OLDER patients" OR DE "OLDER refugees" OR DE "OLDER women" OR DE "ADULT day care centers" OR DE "ELDER care" OR DE "GERIATRICS" OR DE "GERONTOLOGY" OR DE "OLD age" OR DE "OLDER people's attitudes" S35 (MH "Psychological Well-Being") OR (MH "Well-Being (Iowa NOC)") OR (MH "Spiritual Well-Being (Iowa NOC)") OR (MH "Psychological Well-Being (Iowa NOC)") OR (MH "Quality of Life (Iowa NOC)") OR (MH "Quality of Life") OR (MH "Wellness") 148,336 S36 TI (assimila* or accultura* or integrat* or cultural* or culture* or identit* or sociocultural* or multicultural*) OR AB (assimila* or accultura* or integrat* or cultural* or culture* or identit* or sociocultural* or multicultural*) 310,971 S37 TI ( ((meal* or food or eating) N1 (meaning* or habit* or prefer* or context* or practice*)) OR AB ( ((meal* or food or eating) N1 (meaning* or habit* or prefer* or context* or practice*)) 6,781 S38 TI ( ("quality of life" or "life quality")) OR AB ( ("quality of life" or "life quality")) 129,970 S39 TI ( ((life or personal*) N0 satisf*)) OR AB ( ((life or personal*) N0 satisf*)) * or migrant* or ethnic* or racial* or minorit* or refugee* or "non western*") OR AB (immigra* or migrant* or ethnic* or racial* or minorit* or refugee* or "non western*") OR KW (immigra* or migrant* or ethnic* or racial* or minorit* or refugee* or "non western*") OR SU (immigra* or migrant* or ethnic* or racial* or minorit* or refugee* or "non western*") 224,847 S27 S10 OR S11 OR S12 OR S13 OR S14 OR S15 OR S16 OR S17 OR S18 OR S19 OR S20 OR S21 OR S22 OR S23 OR S24 OR S25 OR S26 226,421 S28 DE "OLD age -Social aspects" OR DE "OLDER women" OR DE "OLDER men" OR DE "SENILE dementia" OR DE "OLDER parents" OR DE "AGING parents" OR DE "MINORITY older people" OR DE "OLDER immigrants" OR DE "OLDER people" OR DE "CROSS cultural studies on older people" OR DE "OLD age" 15,969

Table 4
Synthesised findings and categories and extracted findings