Table 2. Studies using Mendelian randomization in nutritional psychiatry.

Table summarizes current MR studies in nutritional psychiatry. Discrepancies exist between disorders, and the applicability of existing instruments to other outcomes, or to a combined ‘cross disorder’ cohort may be fruitful. Results are given as odds ratios per standard deviation change in the exposure unless otherwise specified. Abbreviations: IGAP (International Genomics of Alzheimer’s), Psychiatric Genomics Consortium (PGC). For further details of instrument rsids, genes and beta coefficients please refer to the original publication.

	Exposure	Study	Measure	Sample	N	MR Method	SNPs	Results Reported OR / beta/ Hazard ratio/ Risk difference (95% confidence intervals) p-value
VITAMINS	Vitamin D	Maddock 2017 29	Global Cognitive tests	Cross cohort	172,349	Two-sample	2	β 0.00 points per 25(OH)D decreasing allele (0.01, 0.01) p>0.99
			Memory tests					β 0.00 points per 25(OH)D decreasing allele (-0.01, 0.01) p=0.6
		Jorde 2015 28	Cognitive Tests	Tromso Study	5,980	One-sample	4	No overall association
		Mokry 2016 25	Alzheimer’s Diagnosis	IGAP1	54,162	Two-sample	4	OR 0.8 per SD (0.97, 0.66) p=0.021
		Olsson 2017 27	Dementia Diagnosis	Uppsala Longitudinal Study	1,087	One-sample	2	HR 1.04 points per effect allele (0.91, 1.19)
			Cognitive Impairment (MMSE)		408	One-sample	2	OR 1.03 per effect allele (0.80, 1.34)
		Larsson 2018 26	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	7	OR 0.86 per SD (0.78, 0.94) p = 0.002
		Taylor 2016 48	Schizophrenia Diagnosis	PGC2	79,845	Two-sample	4	OR 0.99 per 10% increase (0.97, 1.0)
		Michaelsson 2018 52	Major Depression Diagnosis	PGC	173,005	Two-sample	6	OR 1.02 per SD (0.97, 1.08) p = 0·44
	Vitamin E	Liu 2018 41	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	3	OR 0·96 per SD (0·47,1·94) p =0·936
	Vitamin B6	Tomioka 2018 43	Schizophrenia Diagnosis	Tokushima University Hospital	10,689	One-sample	1	OR 0·99 per SD log(B6) (0·65, 1·51) p= 0·96
	Folate	Larsson 2017 32	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	2	OR 0·98 per SD (0·72, 1·33) p=0·89
		Mollehave 2017 50	Depression (SLCR90_r3)	Health 2006 & Inter 99	4,126	One-sample	2	OR 1·18 per effect allele (0·18, 7·66), P=0·86
	Homocysteine	Hu 2016 33	Alzheimer’s Diagnosis	34 studies	9,397	Two-Sample	1	OR 3·37 per SD (1·90, 5·95) p = 2·9×10-5
		Larsson 2017 32	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	18	OR 0·99 per SD (0·88, 1·11) 0·86
		Roostaei 2018 67	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	13	OR 1·01 per SD (0·89, 1·15), p=0·84
		Numata 2015 44	Schizophrenia Diagnosis	36 Studies	25,599	Two-sample	1	OR 2·15 per SD (1·39, 3·32) p=5·3x10-4
		Kinoshita 201545	Schizophrenia Diagnosis	Meta-analysis	10,378	One-sample	1	OR 1.14 per SD (1.03-1.27), p=1.6x10-2
		Wu 201735	Vascular Dementia Diagnosis	Meta-analysis	1,880	Two-sample	1	OR 4·29 per SD log (hcy) (1·11,16·57) P = 0·03
	B12	Mollehave 2017 50	Depression (SLCR90_r4)	Health 2006 & Inter 99	4,126	One-sample	12	0·96 (0·52,1·79), P=0·91
		Larsson 2018 32	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	7	OR 1·11 per SD (0·95, 1·30) p=0·18
MINERALS	Calcium	Cheng 201942	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	6	OR 0·74 per SD (0·45, 1·22) p=0·23
			Major Depression Diagnosis	PGC	10,640	Two-sample	6	OR 0·92 per SD (0·67, 1·28) p=0·63
			Bipolar Disorder Diagnosis	PGC	41,653	Two-sample	7	OR 1·85 per SD (0·74, 4·65) p=0·19
			Schizophrenia Diagnosis	PGC	65,967	Two-sample	7	OR 1·85 per SD (0·74, 4·65) p=0·19
	Copper	Cheng 201942	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	2	OR 0·87 per SD (0·75, 1·00) p=0·05
			Bipolar Disorder Diagnosis	PGC	41,653	Two-sample	2	OR 0·87 per SD (0·79, 0·97) p=0·01
			Schizophrenia Diagnosis	PGC	65,967	Two-sample	2	OR 0·96 per SD (0·85, 1·08) p=0·47
	Magnesium	Cheng 201942	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	4	OR 0·43 per SD (0·08-2·44) p=0·34
			Major Depression Diagnosis	PGC	10,640	Two-sample	3	OR 1·19 per SD (0·22, 6·61) p=0·84
			Bipolar Disorder Diagnosis	PGC	41,653	Two-sample	4	OR 8·78 per SD (1·16, 66·26) p=0·04
			Schizophrenia Diagnosis	PGC	65,967	Two-sample	4	OR 0·87 per SD (0·24, 3·19) p=0·83
	Iron	Cheng 201942	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	11	OR 1·02 per SD (0·94, 1·14) p=0·48
			Major Depression Diagnosis	PGC	10,640	Two-sample	9	OR 0·98 per SD (0·91, 1·05) p=0·60
			Bipolar Disorder Diagnosis	PGC	41,653	Two-sample	11	OR 1·17 per SD (0·89, 1·29) p=0·45
			Schizophrenia Diagnosis	PGC	65,967	Two-sample	10	OR 1·04 per SD (0·92, 1·18) p=0·55
	Zinc	Cheng 201942	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	2	OR 0·99 per SD (0·85, 1·14) p=0·85
			Major Depression Diagnosis	PGC	10,640	Two-sample	2	OR 0·99 per SD (0·95, 1·03) p=0·66
			Bipolar Disorder Diagnosis	PGC	41,653	Two-sample	2	OR 1·02 per SD (0·91, 1·14) p=0·70
			Schizophrenia Diagnosis	PGC	65,967	Two-sample	2	OR 0·94 per SD (0·86, 1·02) p=0·11
LIPID FAT AND GLUCOSE HOMEOSTASIS	Isoleucine	Larsson 2017 36	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	4	OR 1·35 per SD (1·08,1·69) p=0·007
	Leucine						1	OR 1·16 per SD (95% CI, 0·78–1·72) p=0·46
	Valine						1	OR 1·13 per SD (95% CI, 0·82–1·57 p=0·46
	Fasting Glucose	Weslowska 2017 53	Depression (BDI)	Young Finns Study	1,217	One-Sample	35	-0·43 (-0·79, -0·07) p=0·02
		Li 2018 46	Schizophrenia Diagnosis	PGC	77,096	Two-sample	30	OR 0·84 per SD, (0·71,0·99) p=0·038
				BIO-X	26,026		14	OR 1·04 per SD (0·84,1·27) p=0·737
		Ostegaard 201540	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	36	OR 1·12 per SD (0·97, 1·30) p=0·112
	Fasting insulin and insulin sensitivity	Ostegaard 201540	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	10	OR 1·32 per SD (0·88, 1·98) p=0.18
		Walter 2016 68	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	9	OR 1·17 per unit (1·02,1·34) p=0.02
		Li 2018 46	Schizophrenia Diagnosis	PGC	77,096	Two-sample	13	OR 2·33 per SD (1·40, 3·90) p=0.001
	DHA (Omega 3)	Sallis 2014 51	Perinatal Depression (EPDS)	ALSPAC mothers	2,378	One-sample	4	RD 0·08 (-0·05, 0·22) p=0·21
	Plasma APOE	Rasmussen37	Alzheimer’s Diagnosis	Copenhagen General Population Study and Copenhagen City Heart Study	106,562	One-sample	5	OR 1.41 per mg/dL (1.27, 1.57)
			All Dementia					OR 1.33 per mg/dL (1.25, 1.43)
	Cholesterol & Triglycerides	Proitsi 2014 39	Alzheimer’s Diagnosis	Cross Cohort	10,578	Two-Sample	70	OR 0·95 per unit (0·76,1·21) p=0·69 Total Cholesterol
							40	OR 1·10 per unit (0·89,1·37) p=0·36 Triglycerides
							69	1·01 per unit (0·82,1·24) p=0·96 HDL-c
							55	0·90 per unit (0·65,1·25) p=0·53 LDL-c
		Ostergaard 201540	Alzheimer’s Diagnosis	IGAP	54,162	Two-sample	73	OR 1·94 per SD (1·79-2·10) p=3·1x10-56 Total Cholesterol
							39	OR 0·96 per SD (0·87,1·07) p=0·48 Triglycerides
							71	OR 0·75 per SD (0·69, 0·82) p=1x10-11 HDL-c
							57	OR 2·31 per SD (2·12, 2·50) p=3x10-87 LDL-c
		Benn 201738	Alzheimer’s Diagnosis	Copenhagen General Population Study and Copenhagen City Heart Study	111,194	One-sample	380	OR 0·57 per mmolL-1 (0·27, 1·17) LDL-c
			Vascular Dementia					OR 0·81 per mmolL-1 (0·34, 1·89) LDL-c
			All Dementia					OR 0·66 per mmolL-1 (0·34, 1·26) LDL-c
		Khandaker 201954	Major Depression	UK Biobank	367,703	Two-sample	76	OR 1.02 per SD (0.91–1.14) LDL-c
							86	OR 0.97 per SD (0.91–1.03) HDL-c
							51	OR 1.18 per SD (1.09–1.27) Triglycerides

¹IGAP International Genomics of Alzheimer’s Project

²PGC Psychiatric Genomics Consortium

³SLCR90_r diagnosis depression…

⁴SLCR90_r diagnosis depression…