Obesity and Overweight in Immigrant Children and Youth

Introduction

Childhood obesity is a public health crisis worldwide. In Canada, the prevalence of obesity among children has increased significantly over the past decades. The Canadian Health Measures Survey reported in 2025 (using data from 2022 to 2024) that among children and youth ages 5 to 17, 19% were classified as overweight and 11% as having obesity.

Defining overweight and obesity:

• Using the World Health Organization (WHO) definition, school-aged children and adolescents from 5 to 19 years old are overweight if weight is one standard deviation above the body mass index (BMI) for age and sex (68^th percentile), and obese if weight is two standard deviations above BMI for age and sex (95^th percentile).
• The WHO Growth Charts for Canada were developed by the Canadian Pediatric Endocrine Group, Dietitians of Canada, Canadian Paediatric Society, College of Family Physicians of Canada, and Community Health Nurses of Canada for monitoring the growth of infants and children in public health and primary care.
• This chart accompanying the WHO Growth Charts for Canada provides recommended cut-off criteria to determine overweight and obesity status, separated by age (birth to 2 years; 2 to 5 years; 5 to 19 years). Cut-off points for anthropometric measurements are intended to provide guidance for further assessment, referral or intervention, and should not be used as diagnostic criteria. Always consider longitudinal patterns of growth.

Risk factors for obesity

Several risk factors contribute to the development of childhood obesity. Modifiable risk factors in the early years of life include^[1]-[5]:

• high maternal pre-pregnancy BMI,
• excess maternal gestational weight gain,
• gestational diabetes,
• in utero tobacco exposure,
• high birth weight and rapid infant weight gain,
• no or poor breastfeeding,
• very early introduction of solid foods,
• feeding patterns, and
• diet, suboptimal infant-maternal relationship, shortened infant sleep, low socio-economic status.

Risk factors specific to newcomer children and youth

Risk factors that appear to predispose newcomer children and youth to overweight and obesity include:

• acculturation and time since immigration
• genetic predisposition
• cultural norms
• socio-economic status and food insecurity

Acculturation and time since immigration

Although first-generation immigrant children appear to have lower risk of obesity than children born in the host country, the risk seems to increase with greater acculturationand longer time in Canada.^[6] An early focus on obesity detection and prevention by health care providers is essential. According to some studies, biculturalism (being engaged in both the heritage culture and in the new society) seems to protect against obesity, compared with complete acculturation in the new culture.^[7]

Genetic predisposition

According to Obesity Canada, about 70% of a person’s obesity risk is determined by genetics. The heritability of obesity influences the hypothalamus and its signaling molecules, which play a central role in coordinating energy balance and homeostasis. Epigenetics may contribute to obesity, when combined with an obesogenic environment.^[8]

Cultural norms

Cultural norms in a child’s country of origin can influence risk of obesity after immigration.^[9] For example, in sub-Saharan Africa, South America, and the Caribbean, larger body sizes can be considered a marker of social status, health and success, while thinness has often been associated with poverty and ill health.^[10] Consuming fried foods and soft drinks may be considered a mark of affluence while a diet of vegetables and fruit is less appealing. Some aspects of the Western diet (high-fat, carbohydrate-rich), are being adopted worldwide, which partly explains the obesity pandemic experienced even in developing countries.^[11]

Socio-economic status and food insecurity

In high-resource countries, overweight and obesity are clearly associated with lower socio-economic status (SES). A number of reasons have been proposed^[12]:

• Lack of funds, lack of transportation, and irregular parental work schedules may limit a child’s ability to attend extracurricular activities, a family’s ability to participate in community activities or to access and prepare nutritious food.

• Children living in low-income communities are more likely to have limited access to healthy food, safe outdoor play spaces or recreational facilities. They may spend more time indoors being sedentary on doing screen-based activities.
• High calorie, low-nutritional foods (such as fast food) are often less expensive than healthier choices. Newly arrived families often live in food-desert geographic locations where there is limited access to reasonably priced healthy food options.

At the beginning of the integration process, immigrant families are more likely to experience poverty than people born in Canada.^[13] Overweight and obesity risk over time increases for newcomer children with low SES who immigrate from low-income countries.^[14] This relationship appears to relate to previous experience of food insecurityand families’ degree of acculturation to new norms at a low SES level (the experience of food insecurity may contribute to the belief that a heavier body weight indicates good health).^[14] Refugee children are especially vulnerable because they are more likely to be living in poverty.

Screening and assessing obesity

Young newcomers to Canada should be screened in the same way as Canadian-born children, by using BMI percentiles for children 2 years of age and older, and weight-for-length in younger children.

The WHO published standard growth indicators in 2010, with growth curves based on children from 6 countries (the U.S., Norway, Brazil, India, Ghana and Oman) to better reflect the world population. Asian and southwestern Pacific populations were not represented, however. Because a large percentage of immigrants to Canada come from Asia, practitioners may wish to look at the pattern of the growth curve instead to identify at-risk trends. Practitioners can also consult the Canadian Pediatric Endocrine Group (CPEG) complementary growth curves for a more harmonized view of growth percentiles from 2 to 19 years of age.^[15]

Even though BMI z-score is a reliable measure and easy to use in the primary care setting, it may not appropriately reflect body fat, particularly for some ethnicities. Ethnic-specific cut-off points for BMI and waist circumference are available for adults but not for children.^[6][16] When interpreting BMI, bear in mind that certain ethnic populations tend to develop medical complications at lower BMI than Caucasians.^[17]

The cut-off values and clinical usefulness of waist circumference in children are not well established, and this measurement is not routinely recommended in the primary care setting.

Screening for diabetes, hypertension and hypercholesterolemia

There are no evidence-based recommendations in the literature for metabolic screening specific to immigrant and refugee children. However, current Canadianand U.S. guidelines can serve as a useful reference for screening newcomer children.

Lipid screening: The Canadian Paediatric Society recommends universal lipid screening between 2 and 10 years of age, using a fasting or non-fasting non-high-density lipoprotein cholesterol (non-HDL-C) or an LDL-C test. In cases of definite or probable familial hypercholesterolemia, this screen should be coupled with cascade screening of family members to identify other affected individuals. Selective screening at any time should be considered for children with identified cardiovascular risk factors, medical conditions predisposing to increased risk, or a positive family history of premature cardiovascular disease or dyslipidemia.

Hypertension: All children should have their blood pressure measured yearly, starting at 3 years of age. Hypertension cut-offs for diagnosis are available. Hypertension and elevated blood pressure require appropriate investigation and management.

Type 2 diabetes: The 2018 Diabetes Canada guidelines recommend screening every 2 years using a combination of an A1C and a fasting plasma glucose (FPG) test for children presenting and adolescents with any of the following:

1. ≥3 risk factors in nonpubertal children beginning at 8 years of age or ≥2 risk factors in pubertal children. Risk factors include:
   • Obesity (BMI ≥95th percentile for age and gender)
   • Member of higher-risk ethnic group (e.g., African, Asian, Hispanic, Indigenous or South Asian descent)
   • First-degree relative with type 2 diabetes and/or exposure to hyperglycemia in utero
   • Signs or symptoms of insulin resistance (including acanthosis nigricans, hypertension, dyslipidemia, non-alcoholic fatty liver disease [ALT >3X upper limit of normal or fatty liver on ultrasound])
2. Polycystic ovarian syndrome
3. Impaired fasting glucose and/or impaired glucose tolerance
4. Use of atypical antipsychotic medications

Details on these tests can be found at Diabetes Canada. There are no specific screens for immigrant and refugee children.

Screening for mental health concerns

Having overweight or obese can affect a child’s mental health, well-being, and family life. Low self-esteem, bullying, insomnia, behaviour problems, and depression are among the common consequences of obesity.

Immigrants often face barriers to access outpatient mental health care, partly because of the heightened stigma attached to mental health disorders.^[18] Health care providers should be alert to such issues, ask their young patients about them, and put them and the family in contact with supportive services as needed. More information on promoting mental health in immigrant and refugee children and youth is available in this resource.

Preventing obesity

Early detection and prevention are essential components of obesity management. Specific preventive measures for obesity in young immigrants have not been well identified. Recommendations are the same as for Canadian-born children, with a focus on three different interventions to adopt healthy living habits: improving diet, increasing physical activity and reducing screen time, and promoting sleep. The 5-2-1-0 framework offers easy-to-follow guidelines: 5 or more serving of vegetables or fruits per day, 2 hours or less of screen time per day, 1 hour or more of physical activity daily, 0 sugar-sweetened beverages.

Prevention measures must be implemented early on in life. Obesity in infancy is an important risk factor for overweight and obesity in adolescence and later on in adulthood. A retrospective analysis showed that the most rapid weight gain occurs between 2 and 6 years of age and that 90% of children obese at age 3 are overweight or obese in adolescence.^[19] The impact of obesity on life expectancy also requires strong prevention strategies.^[20]

Upstream interventions such as early learning and child care settings are key to obesity prevention. Be aware of and address caregivers’ cultural beliefs and practices pertaining to child feeding. In a setting with multiple caregivers, parents should work on providing uniform messages about feeding and healthy living habits. Public, consistent and clear messages based on evidence-based strategies should be shared with caregivers at all levels (parents, child care providers, early childhood educators, teachers, etc.).^[4]

Some examples of population-level, government-led interventions include restricting sales of energy drinks to minors, limiting junk food advertising, enforcing calorie-labelled menus, taxing sugary products, and promoting primary school physical activity.^[21]

Parents and other adults can also model healthy behaviours and help to instill lasting lifestyle habits in children.

Dietary improvements

Efforts to improve both the quality and quantity of newcomer families’ food intake can use Canada’s Food Guide, which is available in multiple languages and includes versions that reflect different ethnic and cultural backgrounds. For newcomers, consider suggesting dietary adaptations that are consistent with traditional eating habits. The expertise of dietitians and trained interpreters may also help.

Specific recommendations for babies include:

• Exclusive breastfeeding until 6 months of age and continued breastfeeding with complementary foods for 2 years and beyond.
  • Continue to breastfeed
  • Limit formula or milk feedings to 450mL to 600mL (15 to 20oz) per day
  • Limit juice to 120mL (4 oz) per day, and always prefer water to juice

• Introducing complementary, iron rich foods beginning around 4-6 months of age.
• After 6 months of age:

For all ages:

• Limit salt and sugar in food (added sugar should represent less than 10% of total calories).
• Serve home-prepared foods and limit fast food.
• Respect normal variation in appetite without forcing children to finish their plate
• Give appropriate portion size.
• Do not use food as a punishment or reward.
• Eat meals together, with family and friends.
• Avoid eating in front of screens.

Physical activity

The CPS position statement on healthy childhood development through outdoor risky play provides developmentally appropriate strategies for encouraging physical activity and reducing sedentary time (particularly screen time) in children and youth.

Canada’s 24-hour movement guidelines recommend that children aged 5 to 17 years accumulate at least 60 minutes per day of moderate to vigorous physical activity involving a variety of aerobic activities. Vigorous physical activities, and muscle and bone strengthening activities should each be incorporated at least 3 days a week.

When looking at the relationship between moderate-to-vigorous physical activity and health outcomes, there is no evidence of a variation between ethnicities.^[22] Health professionals can encourage family participation in community or culturally based activities (e.g., traditional dance) or sports that are popular internationally (e.g., soccer). Activities that offer tax credits should also be encouraged.

Sleep

Establishing healthy sleep habits can help other routines, such as mealtimes, become more predictable and regular. Well rested children and teens will have more positive energy to give to physical activities. Shorter sleep durations in infancy and childhood are associated with a higher obesity risk.^[23] Food choices are often influenced by inadequate sleep and irregular daily routines.

Minimizing screen time also has an impact on sleep patterns, the level of physical activity and ultimately the development of overweight and obesity. The Canadian Paediatric Society has guidelines on screen time in young children and school-aged children and adolescents.

Managing obesity

Like primary prevention, managing obesity is focused on three main interventions: regular physical activity, a healthy diet, and adequate sleep.

A family-centred approach and supportive home environment are important for encouraging and reinforcing lifestyle changes. Practitioners may want to consider family counselling and behavioural therapy with ongoing follow-up in complex cases. Multi-component behaviour-changing interventions (behaviour change, physical activity, diet) have been associated with decreased BMI in children and youth.^[24] Coordination with childcare or school programs can be helpful. Addressing mental health stressors is often a key component of global treatment and patient support.

Source: Managing obesity in children: a clinical practice guideline, CMAJ 2025;197(14):E372-E389

Different pharmacological options approved by Health Canada (e.g., Orlistat, Liraglutide) are used in some adults as part of the treatment of obesity. There are no clear recommendations for their use in prepubertal children.

Guidelines for managing paediatric obesity were published in Canada in 2025, and include recommendations for behavioural and psychological interventions, as well as tailored therapy and support using shared decision-making between health care providers and families. Guideline authors note that while recommendations aimed to consider sub-groups (including those with diverse ethnic and cultural backgrounds), the available literature was limited on the impact of these different intervention modalities on a range of health outcomes.

What health professionals can do

Ask about families’ views on food, eating and weight, to better understand their beliefs and to help negotiate a prevention or treatment plan. For example:

• Ask about the family’s background. Obesity is not considered a disease in many cultures. If deprivation was the norm in their country of origin, parents may continue practices that promote weight gain.
• Assess the parent’s knowledge and beliefs about child health and disease by eliciting their vision of the health system. This approach can provide valuable information about perceptions on obesity and other health issues. Parents may not be aware of the risks of obesity or the importance of following a treatment regimen. They might rely on a child’s ‘growing out’ of overweight naturally or believe that lifestyle changes will make little difference.
• Explore and evaluate social supports, family roles and responsibilities, and a parent’s readiness to change. Extended family members can play an important role, especially if they resist or challenge a parent’s efforts to manage diet. Consider asking: Who cares for the child when the parents are not around? Who prepares the child’s meals? Who lives with the child?
• If appropriate, ask about infant feeding practices and introducing first complementary foods (what and when).
• Assess the family’s intake of carbohydrates and beverages, as well as nutritional quality, and gauge the acceptability of making substitutions.
• Assess parental attitudes to diet, physical activity, body size in children, screen use, and sleep.

When applying culturally sensitive, shared decision-making, health professionals should acknowledge their own values and personal biases.The LEARN model^[25] is one framework for teaching culturally safe care that is action-oriented and focused on what health care providers can do:

• Listen with sympathy and understanding to the patient’s perception of a problem
• Explain your own perception of a problem
• Acknowledge and discuss differences and similarities
• Recommend treatment
• Negotiate agreement

Newcomer children’s risk of having overweight or obesity increases with time lived in the new country, along with the long-term consequences of these conditions, such as type 2 diabetes and cardiovascular disease. Ongoing follow-up and regular assessment are essential.

Selected resources

• Ball, Geoff D. C., et al. Managing Obesity in Children: A Clinical Practice Guideline. CMAJ:197(14); p. E372-E389. doi:10.1503/cmaj.241456
• Canadian Society for Exercise Physiology. Canadian 24-hour Movement Guidelines.
• Le CHU Sainte-Justine. ABCdaire du suivi collaboratif des 0-5 ans
• Food and Agricultural Association of the United Nations. Food-based dietary guidelines from around the world.
• Obesity Canada. 5 Facts about obesity everyone should know
• Obesity Canada: Resources for healthcare professionals
• Rourke Baby Record for infants and children to 5 years of age.
• University of Guelph. NutriSTEP: Nutrition screening tool for toddlers and preschoolers
• WHO. Obesity and overweight. Geneva, Switzerland: WHO, 2025

Information for parents

• Canadian Paediatric Society. Screen time and young children
• Canadian Paediatric Society. Screen use and digital media: Advice for parents of school-aged children and teens
• Canadian Paediatric Society. Physical activity for children and youth
• Health Canada. Canada’s Food Guide. Available in a number of languages.
• Public Health Agency of Canada. Health promotion: Healthy living
• Canadian Society for Exercise Physiology. Canadian 24-Hour Movement Guidelines

References

1. Woo Baidal JA, Locks LM, Cheng ER et al. Risk factors for childhood obesity in the first 1,000 days: a systematic review. American Journal of Pediatrics. 2016;50(6):761-79.
2. Wallby T, Lagerberg D, Magnusson M. Relationship Between Breastfeeding and Early Childhood Obesity: Results of a Prospective Longitudinal Study from Birth to 4 Years. Breastfeeding medicine: the official journal of the Academy of Breastfeeding Medicine. 2017;12:48-53.
3. Cheng TS, Loy SL, Toh JY et al. Predominantly 400nighttime feeding and weight outcomes in infants. The American Journal of Clinical Nutrition. 2016;104(2):380-8.
4. Hassink SG. Early Child Care and Education: A Key Component of Obesity Prevention in Infancy. Pediatrics. 2017;140(6).
5. Uwaezuoke SN, Eneh CI, Ndu IK. Relationship Between Exclusive Breastfeeding and Lower Risk of Childhood Obesity: A Narrative Review of Published Evidence. Clinical Medicine Insights Pediatrics. 2017;doi: 10.1177/1179556517690196
6. Quon, C, McGrath JJ, and Roy-Gagnon MH. Generation of Immigration and Body Mass Index in Canadian Youth. Journal of Pediatric Psychology. 2012;37(8:843-53. doi:10.1093/jpepsy/jss037. PMID 22366576; PMCID: PMC5756084.
7. Wang S, Quan J, Kanaya AM et al. Asian Americans and obesity in California: a protective effect of biculturalism. Journal of Immigrant and Minority Health. 2011;13(2):276-83.
8. Singh RK, Kumar P, Mahalingam K. Molecular genetics of human obesity: A comprehensive review. Comptes rendus biologies. 2017;340(2):87-108.
9. Pena MM, Dixon B, Taveras EM. Are you talking to ME? The importance of ethnicity and culture in childhood obesity prevention and management. Childhood Obesity. 2012;8(1):23-7.
10. Hurston, Jamaiica, et al. An Overview of Body Size Preference, Perception and Dissatisfaction in Sub-Saharan Africans Living in the United States. Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy. 2024;17: 3279–93, doi:10.2147/DMSO.S474956.
11. Popkin BM, Adair LS, Ng SW. Global nutrition transition and the pandemic of obesity in developing countries. Nutrition Reviews. 2012;70(1):3-21.
12. Kral TVE, Chittams J, Moore R. Relationship between Food Insecurity, Child Weight Status, and Parent-Reported Child Eating and Snacking Behaviors. Journal for Specialists in Pediatric Nursing. 2017;22(1) e12177.
13. Sanou D et al. Acculturation and Nutritional Health of Immigrants in Canada. Current Nutrition & Food Science, 2013 9(4): 313–323.
14. Cheah CS, Van Hook J. Chinese and Korean immigrants' early life deprivation: an important factor for child feeding practices and children's body weight in the United States. Social Science & Medicine. 2012;74(5):744-52.
15. Lawrence S, Cummings E, Chanoine JP, Metzger DL, Palmert M, Sharma A, et al. Canadian Pediatric Endocrine Group extension to WHO growth charts: Why bother? Paediatrics & Child Health. 2013;18(6):295-7.
16. Wharton S, Lau DCW, Vallis M et al. Obesity in adults: a clinical practice guideline. CMAJ. 2020;192(31): E875–E891. doi:10.1503/cmaj.191707
17. Ziauddeen N, Wilding S, Roderick PJ, et al. Predicting the risk of childhood overweight and obesity at 4–5 years using population-level pregnancy and early-life healthcare data. BMC Medicine. 2020;18:105.
18. Saunders NR, Gill PJ, Holder L et al. Use of the emergency department as a first point of contact for mental health care by immigrant youth in Canada: a population-based study. CMAJ. 2018;190(40): E1183-e91.
19. Geserick M, Vogel M, Gausche R, et al. Acceleration of BMI in Early Childhood and Risk of Sustained Obesity. NEJM. 2018;379(14):1303-12.
20. Bhaskaran K, Dos-Santos-Silva I, Leon DA et al. Association of BMI with overall and cause-specific mortality: a population-based cohort study of 3.6 million adults in the UK. The Lancet Diabetes & Endocrinology. 2018;6(12):944-53.
21. Owen J. Childhood obesity: government's plan targets energy drinks and junk food advertising. BMJ (Clinical research ed). 2018;361:k2775.
22. Office of Disease Prevention and Health Promotion. Physical Activity Guidelines Advisory Committee Scientific Report. 2018.
23. Magee L, Hale L. Longitudinal associations between sleep duration and subsequent weight gain: a systematic review. Sleep Medicine Reviews. 2012;16(3):231-41.
24. Mead E, Brown T, Rees K et al. Diet, physical activity and behavioural interventions for the treatment of overweight or obese children from the age of 6 to 11 years. The Cochrane Database of Systematic Reviews. 2017;6: Cd012651.
25. Berlin EA, and Fowkes Jr. WC. A Teaching Framework for Cross-Cultural Health Care: Application in Family Practice. Western Journal of Medicine 1983.139(6)934-8.