Prevalence of Overweight and Obesity in Infants and Their Association with Breastfeeding Practices

By Ariba Siddiqui, Rozina Muhammad Iqbal, Anosha Muhammad Aslam, Arshalooz Jamila Rahman

Affiliations

1. Department of Paediatrics and Child Health, Aga Khan University Hospital, Karachi, Pakistan

doi: 10.29271/jcpsp.2026.08.1028

ABSTRACT
Objective: To find out the prevalence of overweight and obesity and to examine their association with breastfeeding practices among infants aged 9-12 months.
Study Design: A prospective cross-sectional study.
Place and Duration of the Study: Department of Paediatrics and Child Health, Aga Khan University Hospital, Karachi, Pakistan, from March to August 2022.
Methodology: A total of 211 infants aged 9-12 months were included using non-probability consecutive sampling. Sociodemographic data, breastfeeding practices, and dietary diversity were recorded through a structured questionnaire. Anthropometric measurements were obtained. According to the WHO growth standards, weight-for-height z-scores were computed; scores above +2 standard deviations were categorised as overweight, while scores above +3 standard deviations were classified as obesity. Logistic regression was used to examine the link between breastfeeding practices and overweight/obesity, adjusting for confounders.
Results: Overweight and obesity were observed in 23 (10.9%) of infants. Overweight and obesity were more prevalent in infants receiving non-exclusive breastfeeding, with 22 out of 120 (18.3%) affected, compared to only 1 out of 91 (1.1%) among exclusively breastfed infants (p <0.001). Logistic regression showed that exclusive breastfeeding was associated with a 96% reduction in the odds of excess weight (aOR = 0.04; 95% CI: 0.01–0.31; p = 0.002). Other variables, including maternal BMI, birth order, and dietary diversity, were not significantly associated.
Conclusion: Non-exclusive breastfeeding practice was found to be a significant contributing factor for overweight and obesity in infants. Promoting exclusive breastfeeding could be an effective strategy to reduce early childhood obesity.

Key Words: Overweight, Obesity, Breastfeeding, Infants, Exclusive breastfeeding, WHO growth standards, Maternal BMI.

INTRODUCTION

Childhood obesity has emerged as a significant global health concern.^1,2 The World Health Organisation (WHO) reports that the number of overweight children under the age of five was over 37 million in 2022.³ Although excess weight, particularly obesity, was once considered a problem of high-income countries predominantly, these issues now equally affect populations in lower- and middle-income countries.⁴ Similarly, the burden in Pakistan remains at its peak, with the situation now appearing increasingly difficult to manage. The National Nutrition Survey further highlighted this concern, reporting that the prevalence of overweight cases doubled between 2011 and 2018.⁵
 

Breastfeeding practices have been extensively studied for their potential protective effects against childhood obesity.⁶ Breast milk provides optimal nutrition tailored to an infant's needs and contains bioactive components that regulate energy balance and fat deposition.⁷ In particular, exclusive breastfeeding for the initial six months is associated with a reduced risk of overweight and obesity in later childhood.⁶

Despite global recommendations advocating exclusive breast- feeding, adherence to these practices varies. In Pakistan, the National Nutrition Survey 2018 reported that only 48% of infants under six months were exclusively breastfed,⁵ highlighting a gap between recommended practices and actual feeding  behaviours.

With rising rates of childhood obesity and inadequate breastfeeding practices reported in Pakistan, examining the link between infant feeding patterns and the risk of excess weight is essential. The present study sought to assess the prevalence of overweight and obesity among infants aged 9-12 months, presenting at Aga Khan University Hospital in Karachi and to evaluate their association with breastfeeding habits. Gaining insight into these associations is vital for designing evidence-based interventions that encourage healthy feeding practices and reduce the likelihood of early-onset obesity.

METHODOLOGY

This cross-sectional study was conducted at the Department of Paediatrics and Child Health, Aga Khan University Hospital, Karachi, Pakistan, from March to August 2022, targeting infants visiting the CHC vaccination centre.

Ethical approval was obtained from Aga Khan University’s Ethical Review Committee (ERC # 2022-6631-20459; dated: 24 January 2022). The confidentiality of the participants was preserved by coding records and allocating distinct study IDs. Before participation, informed written consent was obtained from the parents or guardians.

Infants aged 9 to 12 months who were born full-term (37 to 42 weeks of gestation) and were appropriate for gestational age (birth weight between the 10^th and 95^th percentile) were included through non-probability consecutive sampling. Infants with acute or chronic illnesses were excluded, as were those with comorbid conditions, including syndromes (e.g., Down’s, Edwards’, Patau’s), congenital heart disease, chronic lung disease, seizure disorders, birth asphyxia, inborn errors of metabolism, cleft palate, and tracheo-oesophageal fistula.

The required sample size was calculated using OpenEpi software, based on a prevalence of overweight and obesity in Sindh of 5.2%, with a 95% confidence level and an absolute precision of 3%.⁵ Using the formula for a single proportion, the calculated sample size was 211 infants.

A pre-structured pro forma was used to collect the baseline characteristics of the participants. The information recorded included hospital registration numbers, age, gender, gestational age, birth weight, and birth order. Breastfeeding practices were assessed based on WHO definitions, with exclusive breastfeeding defined as the provision of breast milk only, with no other food or drink during the first 6 months of life, except for oral rehydration solutions, multivitamins, or medicines.⁸ Weaning practices were evaluated by recording the frequency of meals per day and minimum dietary diversity.⁹ According to WHO indicators, infants aged 6-8 months were considered to have adequate feeding if they consumed at least two meals per day, while those aged 9-23 months required a minimum of four meals. Dietary diversity was determined by whether the child’s diet included foods from at least four of the seven recommended groups, namely cereals/roots/tubers, legumes/nuts, dairy, animal- source foods, eggs, vitamin A–rich produce, and other fruits and vegetables.¹⁰

Measurements were taken for infants and their mothers. Infants were weighed on a standardised scale, and their length was measured with an infantometer. Using WHO growth standards, weight-for-height z-scores were calculated, with overweight defined as >+2 SD and obesity as >+3 SD.  Maternal anthropometry included height measured with a stadiometer and weight with a calibrated scale, after which BMI was computed as kg/m².¹¹

Data analyses were performed using SPSS version 26. Des-criptive statistics included means and standard deviations for continuous data, while categorical data were presented as frequencies and percentages. Inferential statistics were performed using chi-square tests for categorical variables and independent t-tests for continuous variables. Variables were selected for multivariable analysis based on univariate screening and clinical relevance. Multivariable binary logistic regression was used to assess the independent association of breastfeeding with overweight/obesity after adjusting for potential confounders, including maternal BMI, birth order, and dietary diversity. Adjusted odds ratios (aORs) with 95% confidence intervals were reported, and significance was set at p <0.05.

RESULTS

A total of 211 infants aged 9-12 months were included in the study. The mean age of the children was 10.20 ± 1.04 months. The majority of infants (132, 62.6%) were male, and 79 (37.4%) were female. The mean maternal BMI was 24.15 ± 3.09 kg/m², with 124 (58.8%) mothers having a BMI between 18.5 and 24.9 kg/m², 74 (35.1%) between 25 and 29.9 kg/m², and 7 (3.3%) 30 kg/m² and above. Most infants were first- or second-born (112, 53.1%). Exclusive breastfeeding was reported in 91 (43.1%) infants, while 120 (56.9%) received mixed feeding. Regarding feeding practices, 160 (75.8%) of infants consumed fewer than four meals per day, and only 51 (24.2%) met the minimum meal frequency. Dietary diversity was limited, with only 149 (70.6%) consuming dairy products and 154 (73%) consuming eggs (Table I). Based on WHO growth standards, 23 infants, representing 10.9% of the sample, were categorised as overweight or obese.

Table II summarises the bivariate analysis of sociodemographic and nutritional factors, with overweight and obesity status. Significant associations were observed for breastfeeding practices. Infants receiving non-exclusive breastfeeding had a significantly higher prevalence of overweight/ obesity, with 22 out of 120 (18.3%) affected, compared with 1 out of 91 (1.1%) among infants receiving exclusive breastfeeding (p < 0.001). Variables such as age, gender, maternal BMI, birth order, meal frequency, and dietary diversity did not show significant associations.

Analysis using multivariable logistic regression identified non-exclusive breastfeeding as a strong predictor of overweight and obesity. Exclusively breastfed infants had markedly lower odds of excess weight (aOR = 0.04; 95% CI: 0.01 – 0.31; p = 0.002). No other factors, including age, gender, maternal BMI, birth order, or minimum meal frequency, were significantly associated with overweight and obesity after adjustment (Table III).

Table I: Sociodemographic and nutritional characteristics of the infants (n = 211).

Variables	Frequency (n)	Percentage (%)
Age of the children, months (Mean ± SD)	10.20 ± 1.04
9	68	32.3
10	62	29.4
11	52	24.6
12	29	13.7
Gender
Male	132	62.6
Female	79	37.4
Maternal BMI, kg/m2
<18.5	6	2.8
18.5 to 24.9	124	58.8
25 to 29.9	74	35.1
≥30	7	3.3
Birth order	-	-
1-2	112	53.1
3 or more	99	46.9
Breastfeeding practices	-	-
Exclusive breastfeeding	91	43.1
Non-exclusive breastfeeding	120	56.9
Minimum meal frequency	-	-
<4	160	75.8
≥4	51	24.2
Minimum dietary diversity	-	-
Grain-based food	206	97.6
Green leafy vegetables	111	52.6
Other fruits and vegetables	201	95.3
Meat	151	71.6
Beans	64	30.3
Egg	154	73.0
Dairy products	149	70.6

Table II: Distribution of sociodemographic and nutritional factors by overweight and obesity status among infants (n = 211).

Variables	Overweight and obesity			p-values
	Yes (n = 23)		No (n = 188)
	n (%)		n (%)
Age of the children, months (mean ± SD)	10.26 ± 1.01		10.19 ± 1.04	0.764
Gender
Male	16 (12.1)		116 (87.9)	0.462
Female	7 (8.9)		72 (91.1)
Maternal BMI, kg/m2 (mean ± SD)                                                                                       23.55 ± 2.84			24.23 ± 3.12	0.327
Birth order
1-2	13 (11.6)		99 (88.4)	0.726
≥3	10 (10.1)		89 (89.9)
Minimum meal frequency
<4	15 (9.4)		145 (90.6)	0.208
≥4	8 (15.7)		43 (84.3)
Minimum dietary diversity
Grain-based food	22 (10.7)		184 (89.3)	0.442
Green leafy vegetables	11 (9.9)		100 (90.1)	0.627
Other fruits and vegetables	22 (10.9)		179 (89.1)	>0.999
Meat	20 (13.2)		131 (86.8)	0.083
Beans	7 (10.9)		57 (89.1)	0.991
Egg	17 (11.0)		137 (89.0)	0.916
Dairy Products	17 (11.4)		132 (88.6)	0.713
Breastfeeding practices
Exclusive breastfeeding	1 (1.1)		90 (98.9)	<0.001*
Non-Exclusive breastfeeding	22 (18.3)		98 (81.7)
Independent t-test applied; chi-square/Fisher’s exact test applied; *p <0.05.

 Table III: Regression analysis of factors associated with overweight and obesity.

	Adjusted odds ratio (95% CI)	p-values
Age of the children, months	1.12 (0.69-1.80)	0.645
Gender
Male	1.46 (0.53-3.97)	0.463
Female	Reference
Maternal BMI, kg/m2	0.92 (0.78-1.09)	0.362
Birth order
1-2	1.36 (0.53-3.52)	0.527
≥3	Reference
Minimum meal frequency
<4	0.52 (0.17-1.53)	0.233
≥4	Reference
Breastfeeding practices
Exclusive breastfeeding	0.04 (0.01-0.31)	0.002
Non-exclusive breastfeeding	Reference
Multivariable logistic regression (enter method) was applied to estimate aORs with 95% confidence intervals. A p-value of <0.05 was considered statistically significant.

DISCUSSION

Early-life feeding practices, particularly breastfeeding, play a critical role in shaping a child’s risk of developing obesity.⁶ This study addresses a gap in evidence regarding the relationship between breastfeeding practices and early childhood overweight/obesity in Pakistan. Results indicated that infants who were not exclusively breastfed had significantly higher odds of being overweight or obese, whereas exclusive breastfeeding was linked with a markedly lower risk. Other factors, including maternal BMI, birth order, and dietary diversity, did not show significant associations with weight status in this cohort.

The current study findings highlight the protective effect of exclusive breastfeeding against infant overweight and obesity, which aligns with international research. Similar to global evidence, infants who were exclusively breastfed in the current study had a markedly lower risk of developing excess weight.¹² This is particularly relevant for Pakistan, and Karachi in particular, where exclusive breastfeeding rates remain suboptimal due to cultural practices, early introduction of formula feeding, and the challenges faced by working mothers in urban settings. Strengthening awareness, improving family and community support, and ensuring workplace-friendly policies for lactating women could therefore play a vital role in improving exclusive breastfeeding practices and reducing the risk of early childhood obesity in this population. Similarly, a meta-analysis by Horta et al. supported the conclusion that exclusive breastfeeding is protective against childhood obesity across diverse populations.¹³

In Pakistan, the findings of this study corroborate results from a recent analysis exploring infant feeding indicators, which reported that breastfeeding was inversely associated with adverse nutritional outcomes, including overweight, in children.⁵ Another local study highlighted the role of maternal knowledge and breastfeeding practices in preventing childhood obesity, emphasising the need for awareness programmes targeting breastfeeding benefits.¹⁴

A systematic review synthesising findings from sibling-pair and intervention trials indicated that human milk feeding was associated with a decreased risk of overweight and obesity after 2 years of age, with stronger protection observed when feeding extended beyond 6 months. The authors cautioned, however, that residual confounding could not be eliminated, and concluded that evidence was inadequate to establish whether the length of breastfeeding among already breastfed infants had a measurable effect on later obesity risk.¹⁵

A review article exploring the mechanisms linking breastfeeding to obesity prevention outlines several pathways through which breastfeeding may offer protective effects. While some of the observed associations may be explained by confounding factors, evidence suggests that breastfeeding plays a direct role in reducing the risk of obesity. Breastfeeding supports an infant’s ability to self-regulate food intake, minimising the likelihood of overfeeding. Additionally, it helps prevent caregiver-driven feeding behaviours that could interfere with the infant’s natural regulation of intake. Furthermore, breast milk contains bioactive components that influence energy balance, including energy intake, expenditure, and cellular metabolism. Together, these mechanisms contribute to slower growth rates and lower fat accumulation in breastfed infants, ultimately reducing their risk of obesity later in life.¹⁶ Previous studies highlighted the role of leptin, a key component of breast milk, in reducing the risk of obesity.^17,18

A study conducted in Pakistan identified several key factors influencing the practice of exclusive breastfeeding.¹⁹ These included regional differences, maternal education levels, maternal age, the child’s size, and exposure to television. The findings highlight the multifaceted nature of breastfeeding practices, emphasising the role of both socio-demographic and behavioural factors in shaping maternal choices. Addressing these determinants through targeted interventions may help promote exclusive breastfeeding and its associated health benefits. Another study has reported maternal education and recommended coverage of antenatal and postnatal care for mothers as factors influencing breastfeeding practice.²⁰

In the context of Pakistan, where breastfeeding practices are often influenced by cultural norms, maternal employment, and lack of awareness, the findings underscore the critical role of exclusive breastfeeding in preventing early childhood obesity.^21,22 Strengthening baby-friendly hospital initiatives, expanding mother-to-mother support groups, and ensuring counselling on exclusive breastfeeding at antenatal and postnatal visits could have a substantial impact. In urban centres such as Karachi, workplace support for lactating mothers and awareness campaigns through community health workers and electronic media are essential to address the rising burden of childhood obesity. Prioritising exclusive breastfeeding promotion within existing maternal and child health programmes can serve as a cost-effective strategy to curb the early onset of obesity and its long-term health consequences in Pakistani children.

This study has several notable strengths, including its focus on infants aged 9-12 months, a critical developmental stage, and the use of WHO growth standards, which allows comparison with international evidence. It also contributes valuable local data on breastfeeding and nutrition practices in Pakistan, where research in this area remains limited. Nonetheless, certain limitations must be acknowledged: the cross-sectional design prevents causal inferences, reliance on parental recall may introduce bias, and the sample drawn from a tertiary care vaccination centre may not reflect the wider population. Additionally, unmeasured factors such as maternal diet, infant activity, and genetic predisposition could have influenced the findings. Future research should prioritise longitudinal and community-based studies to establish causality and improve generalisability, while also incorporating maternal nutrition, infant lifestyle, and genetic factors.

CONCLUSION

This study highlights the significant association between breastfeeding practices and the risk of overweight and obesity in infants aged 9-12 months. Non-exclusive breastfeeding was identified as a key predictor of early childhood overweight and obesity, emphasising the protective role of exclusive breastfeeding. While other factors, such as maternal BMI, birth order, and dietary diversity, showed no significant associations, the findings underscore the importance of promoting exclusive breastfeeding as a preventive strategy against obesity. Public health interventions should focus on raising awareness and addressing barriers to exclusive breastfeeding, particularly in settings with low adherence rates. Future research is needed to explore long-term outcomes and other contributing factors to childhood obesity in diverse populations.

ETHICAL APPROVAL:
Ethical approval was obtained from the Ethical Review Committee of Aga Khan University, Karachi, Pakistan (ERC # 2022-6631-20459; dated: 24 January 2022).

PATIENTS’ CONSENT:
Informed consent was obtained from parents/guardians of eligible infants.

COMPETING INTEREST:
The authors declared no conflict of interest.

AUTHORS’ CONTRIBUTIONS:
AS, RMI: Conception of the study and drafting of the manuscript.
AS, AMA, AJR: Data collection, statistical analysis, literature review, data interpretation, and critical revision for important intellectual content.
All authors approved the final version of the manuscript to be published.
 

REFERENCES

1. Bhutta ZA, Norris SA, Roberts M, Singhal A. The global challenge of childhood obesity and its consequences: What can be done? Lancet Glob Health 2023; 11(8):e1172-3. doi: 10. 1016/S2214-109X (23)00284-X.
2. Thomas-Eapen N. Childhood obesity. Prim Care 2021; 48(3): 505-15. doi: 10.1016/j.pop.2021.04.002.
3. World Health Organisation. Obesity and Overweight: Key Facts. Geneva: World Health Organisation; 2023 [cited 2024 Nov 26]. Available from: httpss://www.who.int/news-room/fact- sheets/detail/obesity-and-overweight.
4. NCD Risk Factor Collaboration (NCD-RisC) Worldwide trends in body-mass index, underweight, overweight, and obesity from 1975 to 2016: A pooled analysis of 2416 population-based measurement studies in 128.9 million children, adolescents, and adults. Lancet 2017; 390(10113):2627–42. doi: 10.1016/S0140-6736(17)32129-3.
5. Government of Pakistan, UNICEF. National Nutrition Survey 2018: Key findings report. Islamabad: Ministry of National Health Services, Regulations and Coordination; 2019 [cited 2024 Nov 26]. Available from: httpss://www.unicef.org/ pakistan/media/2861/file/NNS%20KFR.pdf.
6. Qiao J, Dai LJ, Zhang Q, Ouyang YQ. A meta-analysis of the association between breastfeeding and early childhood obesity. J Pediatr Nurs 2020; 53:57-66. doi: 10.1016/j.pedn.2020.04.024.
7. Sánchez C, Franco L, Regal P, Lamas A, Cepeda A, Fente C. Breast milk: A source of functional compounds with potential application in nutrition and therapy. Nutrients 2021; 13(3):1026. doi: 10.3390/nu13031026.
8. World Health Organisation. Exclusive Breastfeeding for Optimal Growth, Development and Health of Infants. Geneva: World Health Organisation; [cited 2024 Nov 26]. Available from: httpss://www.who.int/tools/elena/interventions/exclusive- breastfeeding.
9. World Health Organisation. Guideline: Complementary Feeding of Infants and Young Children 6–23 Months of Age. Geneva: World Health Organisation; 2021 [cited 2024 Nov 26]. Available from: httpss://www.who.int/publications/i/item/97892 40081864.
10. World Health Organisation. Indicators for Assessing Infant and Young Child Feeding Practices: Definitions and Measurement Methods. Geneva: World Health Organisation; 2021 [cited 2024 Nov 26]. Available from: httpss://www.who.int/ publications/i/item/9789240018389.
11. World Health Organisation. WHO Child Growth Standards: Length/Height-For-Age, Weight-For-Age, Weight-For-Length, Weight-For-Height and Body Mass Index-For-Age: Methods and Development. Geneva: World Health Organisation; 2006 [cited 2024 Nov 26]. Available from: httpss://www.who.int/ publications/i/item/924154693X.
12. Binns C, Lee M, Low WY. The long-term public health benefits of breastfeeding. Asia Pac J Public Health 2016; 28(1):7-14. doi: 10.1177/1010539515624964.
13. Horta BL, Loret de Mola C, Victora CG. Long-term consequences of breastfeeding on cholesterol, obesity, systolic blood pressure and type 2 diabetes: A systematic review and meta-analysis. Acta Paediatr 2015; 104(467):30-7. doi: 10. 1111/apa.13133.
14. Hudaib M, Hussain L, Nazim L, Mohi Uddin S, Jamil MU, Bham SQ, et al. Understanding childhood obesity in Pakistan: exploring the knowledge, attitudes, and practices of mothers, and influential factors. A cross-sectional study. Front Public Health 2024; 12:1475455. doi: 10.3389/fpubh.2024.1475455.
15. Dewey KG, Gungor D, Donovan SM, Madan EM, Venkatramanan S, Davis TA, et al. Breastfeeding and risk of overweight in childhood and beyond: A systematic review with emphasis on sibling-pair and intervention studies. Am J Clin Nutr 2021; 114(5):1774-90. doi: 10.1093/ajcn/nqab206.
16. Bartok CJ, Ventura AK. Mechanisms underlying the association between breastfeeding and obesity. Int J Pediatr Obes 2009; 4(4):196-204. doi: 10.3109/17477160902763309.
17. Palou M, Pico C, Palou A. Leptin as a breast milk component for the prevention of obesity. Nutr Rev 2018; 76(12):875-92. doi: 10.1093/nutrit/nuy046.
18. Sinkiewicz-Darol E, Adamczyk I, Lubiech K, Pilarska G, Twaruzek M. Leptin in human milk-one of the key regulators of nutritional programming. Molecules 2022; 27(11):3581. doi: 10.3390/molecules27113581.
19. Arif S, Khan H, Aslam M, Farooq M. Factors influencing exclusive breastfeeding duration in Pakistan: a population-based cross-sectional study. BMC Public Health 2021; 21(1):1998. doi: 10.1186/s12889-021-12075-y.
    
     
20. Kumera M, Haidar J. Level of exclusive breastfeeding and its enabling factors among lactating women who delivered in health facilities of Asosa town, Ethiopia: A cross-sectional study. BMC Women's Health 2021; 21(1):432. doi: 10. 1186/ s12905-021-01580-2.
21. Riaz A, Bhamani S, Ahmed S, Umrani F, Jakhro S, Qureshi AK, et al. Barriers and facilitators to exclusive breastfeeding in rural Pakistan: A qualitative exploratory study. Int Breastfeed J 2022; 17(1):59. doi: 10.1186/s13006-022-00495-4.
22. Ahmed F, Malik NI, Shahzad M, Ahmad M, Shahid M, Feng XL, et al. Determinants of infant and young child feeding among mothers of malnourished children in South Punjab, Pakistan: A qualitative study. Front Public Health 2022; 10:834089. doi: 10.3389/fpubh.2022.834089.