Author response table 1. BMI and symptoms of depression, anxiety, and ADHD at age 8 in MoBa, using adult and childhood body size PGS with a p-value threshold of 1.

		Adult BMI PGS, p-value threshold of 1a						Childhood body size PGS, p-value threshold of 1a
		MR estimateb			Within-families MR estimateb			MR estimateb			Within-families MR estimateb
		Beta	CI	p	Beta	CI	p	Beta	CI	p	Beta	CI	p
Depressive symptoms: SMFQc score	Child BMIa	0.43	0.26,0.60	<0.001	0.31	0.06,0.57	0.02	0.1	–0.05,0.24	0.18	–0.06	–0.26,0.14	0.57
	Mother’s BMI				0.04	–0.03,0.12	0.27				0.10	–0.01,0.21	0.09
	Father’s BMI				0.03	–0.07,0.14	0.52				0.10	–0.05,0.25	0.18
Anxiety symptoms: SCAREDd score	Child BMI	–0.25	–0.42,0.08	0.004	–0.34	−0.59,–0.10	0.005	–0.1	–0.24,0.04	0.16	–0.24	−0.43,–0.05	0.01
	Mother’s BMI				0.03	–0.05,0.10	0.48				0.12	0.01,0.23	0.03
	Father’s BMI				0.04	–0.06,0.14	0.42				0.05	–0.09,0.19	0.48
ADHD symptoms: RS-DBDe score	Child BMI	0.48	0.31,0.65	<0.001	0.69	0.43,0.95	<0.001	–0.09	–0.23,0.06	0.24	–0.15	–0.35,0.05	0.15
	Mother’s BMI				–0.05	–0.13,0.03	0.19				0.07	–0.04,0.18	0.24
	Father’s BMI				–0.10	–0.20,0.00	0.06				0.01	–0.13,0.15	0.93
ADHD-inattention symptoms: RS-DBDe score, inattention items	Child BMI	0.44	0.26,0.61	<0.001	0.65	0.39,0.92	<0.001	–0.07	–0.21,0.08	0.37	–0.15	–0.35,0.05	0.15
	Mother’s BMI				–0.06	–0.14,0.02	0.13				0.10	–0.01,0.21	0.09
	Father’s BMI				–0.09	–0.19,0.01	0.08				–0.01	–0.15,0.14	0.93
ADHD-hyperactivity symptoms: RS-DBDe score, hyperactivity items	Child BMI	0.42	0.25,0.60	<0.001	0.59	0.32,0.85	<0.001	–0.09	–0.24,0.06	0.24	–0.12	–0.33,0.08	0.25
	Mother’s BMI				–0.03	–0.11,0.05	0.42				0.02	–0.09,0.13	0.70
	Father’s BMI				–0.08	–0.19,0.02	0.12				0.02	–0.12,0.16	0.80
aCoefficients represent change in symptoms, log-transformed after adding 1, per 5 kg/m2 increase in BMI. bGenetic models adjust for child’s sex, genotyping batch, and the first 20 principal components of ancestry. cShort Mood and Feelings Questionnaire. dScreen for Child Anxiety Related Disorders. eParent/Teacher Rating Scale for Disruptive Behaviour Disorders.