Adolescence is a critical phase for physical and cognitive growth. Healthy adolescent girls influence future maternal and child health outcomes, yet malnutrition among adolescents' girls remains a neglected concern in low- and middle-income countries. In Bangladesh, approximately 31% of adolescent girls are underweight and micronutrient deficiencies remain highly prevalent, reflecting persistent nutritional challenges. This study aimed to assess the nutritional knowledge, dietary practices, and nutritional status of adolescent girls in rural Bangladesh and identify associated factors.

A descriptive cross-sectional study was conducted among 311 adolescent girls aged 10–19 years from a rural school and a college in Patuakhali District, using a purposive sampling technique between February and September 2024. Data were collected using a pre-tested, interviewer-administered questionnaire and anthropometric measurements. Nutritional knowledge and practices were scored dichotomously based on responses to structured questions, with predefined cut-offs used to classify knowledge and practice levels as good or poor, while nutritional status was determined using BMI-for-age percentiles based on WHO standards. Data were analyzed in SPSS v25 using descriptive statistics and Chi-square tests at a significance level of P < 0.05.

Only 22.5% of respondents demonstrated good nutritional knowledge level, and 65.3% had good dietary practices. While 70.4% maintained a healthy BMI, 19.6% were underweight, 7.4% overweight, and 2.6% obese. Significant associations were found between nutritional status and level of education (P = 0.032) and nutritional knowledge (P < 0.001), dietary practice (P = 0.002), and health condition (P < 0.001). Poor knowledge on nutrition, limited access to nutritious food, and skipping breakfast were significantly associated factors for undernutrition. Nearly 90% had never undergone nutritional assessment, and 64% reported at least one clinical symptom of nutrition deficiency.

Rural adolescent girls in Bangladesh face a dual burden of malnutrition associated with poor nutrition knowledge, socioeconomic barriers, and inadequate dietary diversity. School-based nutrition education and improved access to affordable nutritious foods are crucial for breaking the intergenerational cycle of malnutrition.