Adolescent obesity can lead to various diseases such as type 2 diabetes, fatty liver, and dyslipidemia, while increasing the risk of chronic diseases in adulthood. The development of obesity is influenced not only by food types and intake quantity but also by eating behaviors, including eating speed, meal timing, breakfast frequency, and nighttime eating. However, the association between dietary behaviors and obesity among Chinese adolescents remains unvalidated.

To explore the association between dietary behaviors and adolescent obesity, and to provide scientific evidence for effective obesity prevention strategies.

A multistage sampling approach was employed: simple random sampling selected 7 provinces nationwide; convenience sampling identified 16 universities within these provinces; cluster sampling included all first-year students aged 16-19 years from the selected universities. Data on current height, weight, and dietary behaviors were collected via self-administered electronic questionnaires. Statistical analyses (chi-square tests and Logistic regression) were performed using SPSS 26.0 and R 4.3.3.

A total of 16 445 freshmen were surveyed, including 6 710 males (40.80%) and 9 735 females (59.20%), with an average age of (18.04±0.75) years. The highest proportions were in the 18 years (9 618 cases, 58.49%) and 19 years (4 169 cases, 25.35%) age groups, and 5 375 (32.68%) were only children. The overall obesity rate among adolescents was 10.48% (1 723/16 445). The obesity rates of adolescents with much faster, slightly faster, and much slower eating speeds were 15.02% (587/3 908), 9.41% (1 029/10 930), and 6.66% (107/1 607), respectively, and the obesity rate increased with the acceleration of eating speed (P<0.05). The obesity rate of adolescents whose parents were both obese was higher than that of those whose parents were both non-obese [18.89% (17/90) vs 10.10% (1 544/15 293), P<0.05]. There was no significant difference in the obesity rate between males and females whose parents were both obese [16.22% (6/37) vs 20.75% (11/53), P=0.79]; the obesity rate of males whose parents were both non-obese was higher than that of females [12.79% (796/6 225) vs 8.25% (748/9 068), P<0.05]. The obesity rate of adolescents whose fathers were obese but mothers were non-obese was 16.06% (88/548), and the obesity rate of males was lower than that of females [14.29% (38/266) vs 17.73% (50/282), P<0.05]. The obesity rate of adolescents whose mothers were obese but fathers were non-obese was 16.15% (26/161), and the obesity rate of males was higher than that of females [22.03% (13/59) vs 12.75% (13/102), P<0.05]. The results of multivariate Logistic regression analysis showed that males [OR (95%CI)=1.46 (1.31-1.62)], younger age [compared with 19 years old, OR (95%CI) of 16 years old was 1.37 (1.08-1.73), and OR (95%CI) of 17 years old was 1.27 (1.06-1.51)], much faster [OR (95%CI)=2.19 (1.76-2.74)] and slightly faster eating speeds [OR (95%CI)=1.42 (1.15-1.75)], and having breakfast and dinner at home and lunch at school [with an OR (95%CI)=0.86 (0.75-0.98) compared to those who eat at school] were more likely to be obese.

Key risk factors for adolescent obesity in China include male gender, younger age, parental obesity, fast eating speed, and eating location patterns (e.g., school lunches with home breakfast/dinner). Additionally, a potential X-chromosome dominant cross-inheritance pattern of obesity was observed, though further validation is required.

青少年肥胖会导致2型糖尿病、脂肪肝等多种疾病发生，并增加成年后患慢性病的风险。肥胖的发生、发展除与食物种类和进食量有关外，也可能与进食速度、进食时间、早餐频次及夜间进食等进食方式有关，但中国青少年饮食方式与肥胖之间的关联性尚未得到验证。

探讨大学新生肥胖与饮食方式的关系，为有效预防青少年肥胖提供科学依据。

按照简单随机抽样方法，在全国抽取7个省份；按照便利抽样原则，在抽到的7个省份选取16所大学；根据整群抽样原则，将样本大学中所有年龄16~19岁的一年级新生作为研究对象。使用自填式电子问卷收集青少年的身高、体重、既往饮食方式等信息。使用SPSS 26.0和R 4.3.3统计软件，对分类资料进行χ²检验、趋势χ²检验及Logistic回归分析。

共调查16 445名大一新生。其中，男6 710名（40.80%）、女9 735名（59.20%），平均年龄为（18.04±0.75）岁，18岁（9 618名，58.49%）和19岁（4 169名，25.35%）年龄者占比最高，独生子女有5 375名（32.68%）。青少年的总体肥胖率为10.48%（1 723/16 445）。进食速度快很多、稍快、慢很多青少年的肥胖率分别为15.02%（587/3 908）、9.41%（1 029/10 930）、6.66%（107/1 607），肥胖率随进食速度增快而上升（P<0.05）。父母均肥胖的青少年肥胖率高于父母均不肥胖者[18.89%（17/90）比10.10%（1 544/15 293），P<0.05]。父母均肥胖男生和女生的肥胖率比较，差异无统计学意义[16.22%（6/37）比20.75%（11/53），P=0.79]；父母均不肥胖男生的肥胖率高于女生[12.79%（796/6 225）比8.25%（748/9 068），P<0.05]。父亲肥胖而母亲不肥胖青少年的肥胖率为16.06%（88/548），男生肥胖率低于女生[14.29%（38/266）比17.73%（50/282），P<0.05]。母亲肥胖而父亲不肥胖青少年的肥胖率为16.15%（26/161），男生肥胖率高于女生[22.03%（13/59）比12.75%（13/102），P<0.05]。多因素Logistic回归分析结果显示，男生[OR（95%CI）=1.46（1.31~1.62）]、低龄[与19岁相比，16岁的OR（95%CI）=1.37（1.08~1.73），17岁的OR（95%CI）=1.27（1.06~1.51）]、进食速度快[与慢很多相比，快很多的OR（95%CI）=2.19（1.76~2.74），稍快的OR（95%CI）=1.42（1.15~1.75）]、早晚餐在家午餐在学校[在学校就餐与之相比的OR（95%CI）=0.86（0.75~0.98）]的青少年更容易发生肥胖。

性别、年龄、父母是否肥胖、进食速度和进食地点是青少年肥胖的影响因素，男性、低龄、父母肥胖、既往进食速度快、早晚餐在家午餐在学校的青少年更容易肥胖。中国青少年肥胖可能存在X染色体显性交叉遗传现象，但需进一步验证。