The influence of grandparents on grandchildren. Scoping review

Introduction. Grandparents, in particular, are recognized as the "first line of defense" when families are disturbed, disorganized, or in need, often contributing time, care, and financial resources as needed. The ties between grandparents and grandchildren are known for their diversity of content, covering a wide continuum of care and intergenerational support. This study aims to identify, evaluate, and summarize the best available scientific evidence about the influence of grandparents on grandchildren. Method. A systematic search of the relevant literature was conducted in the PubMed, EMBASE, Cochrane Library, CINAHL, PsycINFO, SciELO SCOPUS, WEB OF SCIENCE, and LILACS databases, for articles published up to February 8, 2021, relating to studies evaluating the influence of grandparents on grandchildren. Results. 13 cross-sectional studies were selected. In five studies, financial issues are analyzed and in eight studies nutrition issues are evaluated. The studies were from four different continents – Oceania, Asia, North America, and Europe. Conclusion. Grandparents in the caregiver role influence the grandchildren's upbringing and this influence is linked to the amount of time they spend together. Culture and ethnic factors have a strong impact on this influence. Grandparents contribute to grandchildren concerning finances, regardless of social class or educational level. However, with food, grandparents with a lower educational level than their children, tend to provide a less healthy diet for their grandson. Thus, grandparents are a very valuable audience in awareness campaigns about infant feeding to reduce childhood obesity. y en ocho estúdios fue evaluado cuestiones de nutrición. Los estudios procedían de cuatro continentes diferentes: Oceanía, Asia, América del Norte y Europa. Conclusión. Los abuelos en el rol de cuidadores influyen en la formación de los nietos y esta influencia está ligada al tiempo que pasan juntos. La cultura y los factores étnicos tienen un fuerte impacto en esta influencia. Los abuelos contribuyen a los nietos en lo que respecta a las finanzas, independientemente de la clase social o el nivel educativo. Sin embargo, con la comida, los abuelos con un nivel educativo más bajo que sus hijos, tienden a proporcionar una dieta menos saludable para su nieto. Así, los abuelos son un público muy valioso en las campañas de sensibilización sobre alimentación infantil para reducir la obesidad infantil.


INTRODUCTION
Family, from an evolutionary perspective, indicates an expected biological relationship being a lasting and powerful determinant of social investments, even in modern societies 1 . Multigenerational bond have been identified as increasingly important to ensure well-being, stability, and support for children 2 . For young children, the most influential aspect of the immediate social context is the family 3 .
Grandparents, in particular, are recognized as the "first line of defense" when families are disturbed, disorganized, or in need, often contributing time, care, and financial resources as needed 2,[4][5][6] . The bonds between grandparents and grandchildren are known for their diversity of content, covering a wide continuum of care and intergenerational support 2 .
Since 1990, in the United States of America (USA), there has been a 30% increase in the number of children (half of whom are under the age of six) who live in homes headed by grandparents for various reasons 7 . These include parental incarceration, unemployment, divorce or death, mental illness, abuse and neglect, child abandonment, teenage pregnancy, substance abuse, and child abandonment [7][8][9] .
With the increase in life expectancy, there has been a dramatic increase in the number of multigenerational families and the number of years that individuals can expect to be part of these families 4,5 . Structural changes in the economy have increased interest in intergenerational processes 4 . Trends in government spending indicate a shift towards family responsibility, rather than the state, for caring for individuals who need assistance 4 . The titles of the era of full employment welfare are long gone for many families and individuals; unemployment insurance; a single "living wage" sufficient to support a family; and prosperity for the majority of the working class 4

. A double income has
become an economic necessity for many families, full-time employment is becoming increasingly fragile, and part-time, self-employment and limited-time employment are more common 4 .
Taking care of grandchildren represents one of the most important ways in which grandparents contribute to the wellbeing of their families 10 . In nations with emerging economies, grandparents play an especially important role in caring for grandchildren whose parents have migrated or work full-time 10,11 . There are social and socioeconomic paths through which grandparents influence their grandchildren's chances of life 5,10 . It should keep in mind that, in today's world, children are, most of the time, with their grandparents as caregivers (31.4%) or in the daycare centers (31.4%) most of the time; parents are responsible most of the time in 28.5% 12 . It is reported that grandparents take care of the grandchildren of 44% of British children at least once a week 5 . In the USA, almost 5% of children are raised by grandparents 8 , while in Chinese urban areas 50 to 70% of young children are cared for mainly by grandparents 3 .
In the Northeast of Brazil, the grandparents were referred by their grandchildren, in their majority (80%), as the most important people in their life, that the relationship between them is of authority and that they are reprimanded when they do not obey the grandparents 13 . What the children mentioned most that their grandparents did (92%) was the care with food, clothing, and storytelling/tales 13,14 .
There are several benefits and advantages of affectivity between grandparents and grandchildren, concerning grandchildren we can say that being close to grandparents gives them a sense of security, strengthens family bonds, encourages complicity, and teaches respect for the older adult 15 . The advantages for grandparents, on the other hand: distraction with their grandchildren removes depression, improves self-esteem and they feel useful to their children 15 .
With the grandchildren's affection and attention, the feeling of well-being increases 15 18 .
They found that in all families there were dietary influences from the country of origin of the grandparents, which were also referred to as the best foods 18 . There was also a strong aspect of pride from their food background in Italian and Chinese families, always referred to, by their families, as the "best food". 18 Both Italian families and Chinese families believed that their diet was the healthiest 18 .
Watanabe et al assessed 1765 children, ages 3 to 6 years, in Japan, whose mothers had jobs 20 . The objective was to analyze the effects of maternal employment and the presence of grandparents on the lifestyles of pre-school children 20 . They found that maternal employment was associated with irregular meal times, random snack times, and bedtime after 10 pm, and those families of three generations in the same household were negatively associated with irregular meal times, even after adjusting for children's characteristics and family environments 20 .
However, both maternal employment and families of three generations were significantly associated with children's obesity 20 .
The study by Li et al analyzed whether the weight perception of 1425 children by parents and grandparents differed between boys and girls 19 . Physical examination revealed that 11 girls and 9 boys were underweight (BMI below the 5th percentile) 19 . Of the remaining 1405 children, 327 (203 boys and 124 girls) were overweight or obese 19 .
The univariate analysis showed that male gender, birth weight equal to or greater than 4000 grams, cesarean delivery, prenatal practices related to music, feeding time less than 10 minutes, not choosing food, living together with grandparents, obese father and/or mother and family with higher income was significantly associated with childhood obesity/overweight 19 . However, a significant proportion (70%) of parents and grandparents underestimated their children's weight 19 . Parental underestimation of a child's weight status was also greater for boys compared to girls 19 . o They showed a tendency to encourage children to eat more meals and larger portions.
• Grandparents used food as an educational and emotional tool: o They intend to shape grandchildren's behavior and expressing love and affection through food.
All studies on food assessment are shown in Table 1. Table 1. Summary of studies that analyze the influence of grandparents on the feeding of grandchildren.  According to the study by Silverstein et al, grandparents gave money to 65% of their grandchildren, with younger and/or wealthier grandparents, less functional disability, and fewer paternal grandchildren being more likely than their parents' counterparts to give money to their grandchildren 10 .

Author and year
They also concluded that grandchildren whose parents were men, lastborn and, especially firstborn, received more money than other grandchildren 10  All studies on financial valuation are shown in Table 2.

DISCUSSION
Research related to grandparents raising grandchildren has become increasingly common in the care literature over the past two decades 8,22 . Volutionary psychologists, have argued that grandparents' investment is a natural aspect of  Greater interaction between grandchildren and maternal grandparents than with paternal grandparents; however, paternal grandparents had a higher frequency than maternal grandparents. Maternal grandparents provided more financial benefits than paternal, as well as being more likely to provide essential items and gifts. Grandparents gave money to 65% of their grandchildren; provided higher value transfers to grandchildren whose parents provided greater subsidies or with whom they co-lived without their parents. The probability of making a transfer followed the male line and was greater for families with only grandchildren, in which the parents were firstborn. with grandparents' generosity. Grandparents' economic contributions to grandchildren in rural China are shaped by family demands in a highly mobile society, with interdependence between generations, in a persistent patrilineal gender system that reaches the level of grandchildren

Nutritional influence
The prevalence of childhood overweight (25%) and obesity (8%) in Western countries is a significant public health problem, with an additional 50% of children with health weight presenting likely to become adults overweight or obese, based on the prevalence current overweight and obesity combined of 70% for men and 56% for women 24,25 .
Childhood obesity is associated with an increased risk of chronic diseases, such as cardiovascular disease and diabetes mellitus and also has a profoundly negative effect on children's psychological health 3,18,20,26  Therefore, those responsible can adopt more behaviors aimed at diet and exercise to control the weight of girls than for boys, which can lead to more obese/overweight boys than girls 19 . The main reason for this gender difference may be related to social values and cultural factors 19 .
In the study by Jingxiong et al, the conflict about child nutrition between generations was especially obvious in families with obese children, often generating stressful situations 3 . It must be taken into account that some studies show that social stress can result in insulin resistance and central obesity through the activation of the sympathoadrenal system in the child 33 and that several parents expressed frustration at not being able to influence grandparents way of feeding their children 3 . The main problem seemed to be that while the parents defined the child's obesity as a problem, the grandparents strongly disagreed. 3 he grandparents declared in these families that the child was strong, happy and healthy and not fat 3 , a situation also reported in the study by Li et al 19 . This characteristic was more accentuated when the grandparents were of low educational level and had little knowledge about healthy eating 3,26 . The higher level of education of those responsible for children is a protective factor against childhood obesity 33 . Although the parents disagreed, the grandparents' feeding practices prevailed, as they were the main caregivers 3 . In addition to the fact that grandparents also offer more sweets to children when mothers warned grandparents not to do so 34  nutrition were influenced by their own experiences of poverty, the conception that obesity is a sign of health and that his breeding duty was to provide the only child in the family with large quantities of foods of the kind that the child likes and which are considered nutritious 3,37 . Grandparents offered high-energy foods as a reward for promoting better conduct in children 3,38 . Using food as a reward, however, tends to increase the preference for food to reward, leading to less healthy food preferences in children 3,38 .
However, grandparents encourage children to exercise, restrict their television time, and reduce diets high in calories and fat if they believe that children are obese or overweight 19 . In contrast, they may not restrict these diets if they do not believe that children are obese or overweight 19 .
Grandparents' tendency to underestimate a child's weight can lead children to overeat and exercise less 19 24 .
The culture and the ethnic factors have a strong impact on both the nature of the practices and feeding styles of grandparents, as they influence them 16,18,33,37