College students' depression and body image: Unraveling the Link

Table 1 Demographic characteristics of college students in Southern China

Demographic characteristics	mean ± SD			P value
	Male (n = 706)	Female (n = 580)	Total (n = 1286)
Age (years)	19.78 ± 2.01	19.29 ± 1.72	19.56 ± 1.90	< 0.05
Body mass index (kg/m²)	22.41 ± 3.75	21.78 ± 3.03	22.13 ± 3.46	< 0.01
Body dissatisfaction (kg/m²)	2.92 ± 2.00	2.90 ± 1.82	2.91 ± 1.92	< 0.05
Physical activity score	22.16 ± 21.04	11.19 ± 14.89	17.21 ± 19.31	< 0.01
Diet score	79.64 ± 19.78	91.79 ± 17.93	85.12 ± 19.90	< 0.05
Depression score	43.73 ± 9.68	46.04 ± 9.19	44.77 ± 9.53	< 0.01

Table 2 Results of Pearson’s correlation analysis between the variables

Dimension	Body dissatisfaction	Depression	Diet	Physical activity
Body dissatisfaction	1
Depression	0.2151	1
Diet	0.1431	0.1321	1
Physical activity	-0.1691	-0.1381	-0.1471	1

¹The correlation was significant at the 001 Level (two-tailed).

Table 3 Results of the structural equation modeling path relationship test

Pathway relationship		Estimate	SE	Critical ratio	P value
Physical activity negatively affects body dissatisfaction	Physical activity turns to body dissatisfaction	-0.157	0.003	-5.735	< 0.001
Binge eating positively affects body dissatisfaction	Diet turns to body dissatisfaction	0.114	0.013	3.563	< 0.001
Body dissatisfaction positively affects depression	Body dissatisfaction turns to depression	0.180	0.137	6.535	< 0.001
Physical activity negatively affects depression	Physical activity turns to depression	-0.093	0.013	-3.397	< 0.001
Binge eating positively affects depression	Diet turns to depression	0.148	0.067	4.614	< 0.001

Table 4 Analysis of mediating effects of diet on depression

	Effect value	SE	Lower limit confidence interval	Upper limit confidence interval	Effect size (%)	P value
Total effect	0.0630	0.0132	0.0370	0.0890		< 0.001
Direct effect	0.0492	0.0131	0.0235	0.0750	78.2%	< 0.001
Indirect effect	0.0137	0.0031	0.0081	0.0201	21.8%	< 0.001

Table 5 Analysis of mediating effects of physical activity on depression

	Effect value	SE	Lower limit confidence interval	Upper limit confidence interval	Effect size (%)	P value
Total effect	-0.0681	0.0136	-0.0948	-0.0413		< 0.001
Direct effect	-0.0517	0.0136	-0.0783	-0.0250	75.9%	< 0.001
Indirect effect	-0.0164	0.0032	-0.0234	-0.0106	24.1%	< 0.001

Table 6 Work characteristics curve analysis for participants with body mass index differences

Indicator	Cutoff value	An area under the curve (%)	Sensitivity (%)	Specificity (%)	Jordon’s index (%)	SE	Lower limit confidence interval	Upper limit confidence interval	P value
Body dissatisfaction	1.73	70.0	84.6	46.8	31.4	0.016	0.663	0.727	< 0.001