Table 1.

Characteristics of the studies included in systematic review and meta-analysis.

Publication	Age Group	Matching	Body Composition Analysis	No. of Patients	Groups	Length of Gluten-Free Diet (Year)	Outcome
							Body Weight		Body Mass Index		Fat mass			Fat-Free Mass
							kg	Other Unit	kg/m2	Other Unit	kg	%	Other Unit	kg	%	Other Unit
	Newly diagnosed celiac patients vs. non-celiac control subjects
Capristo et al., 2000 [10]	adults	age, height	ID	39	newly diagnosed	N/A	58.2 ± 6.7				11.6 ± 4.0	20.1 ± 6.8		46.6 ± 7.5	79.9 ± 6.8
				63	control		67.0 ± 6.6				16.9 ± 3.0	25.4 ± 4.0		50.2 ± 6.2	74.8 ± 4.2
Capristo et al., 1997 [15]	adults	age, gender	BIA	16	newly diagnosed	N/A	54.9 (41.0–72.0)		19.9 (16.6–28.8)		13.4 (6.2–30.7)	24.2 (11.1–42.6)		41.8 (30.4–50.9)	76.6 (57.4–89.1)
				20	control		66.4 (57.0–76.0)		23.6 (19.4–26.0)		17.4 (9.9–24.2)	26.7 (14.2–35.9)		49.6 (36.7–60.9)	74.2 (64.1–85.8)
Barera et al., 2000 [26]	children	age, gender	DXA	29	newly diagnosed	N/A	28.3 ± 11.0		16.4 ± 3.8		4.6 ± 3.5	17.4 ± 8.3		21.4 ± 8.4
				29	control		34.5 ± 14.1		18.1 ± 2.8		7.5 ± 4.9	23.7 ± 8.4		23.4 ± 10.3
Björck et al., 2017 [27]	children	age, gender, HLA-DQ	DXA	71	newly diagnosed	N/A	37.2 ± 8.2		17.9 ± 3.0		11.0 ± 5.6			24.8 ± 3.4
				142	control		38.6 ± 8.2		18.5 ± 3.0		11.7 ± 5.5			25.5 ± 3.7
Aurangzeb et al., 2010 [28]	children	age, gender	BIA	25	newly diagnosed	N/A		for age percentile: 45 ± 29.9		percentile: 50.5 ± 31.4			Rush equation: 6.3 ± 7.3			Rush equation: 23.4 ± 11.0
				25	control			for age percentile: 46.6 ± 31.1		percentile: 48.2 ± 32.2			Rush equation: 6.2 ± 6.5			Rush equation: 23.5 ± 11.0
Rätsch et al., 2001 [29]	children	-	DXA	65	newly diagnosed	N/A		Z-score: −2.2 ± 0.1				25.8 ±12.4			74.9 ± 12.3
				71	control			Z-score: −2.1 ± 0.2				24.9 ± 9.5			75.9 ± 9.4
Gallardo et al., 2008 [30] *	children	age, gender	DXA	29	newly diagnosed	N/A	significantly lower in CD than in control subjects		significantly lower in CD than in control subjects		significantly lower in CD than in control subjects			significantly lower in CD than in control subjects
				32	control
	Celiac patients at diagnosis vs. same patients after at least a one-year gluten-free diet
Capristo et al., 2000 [10]	adults	N/A	ID	39	before a GFD		58.2 ± 6.7				11.6 ± 4.0	20.1 ± 6.8		46.6 ± 7.5	79.9 ± 6.8
					on a GFD	1.0 ± 0.0	60.9 ± 6.2				13.8 ± 3.7	22.9 ± 6.2		47.1 ± 7.0	77.2 ± 6.1
Barera et al., 2000 [26]	children	N/A	DXA	20	before a GFD		30.3 ± 11.5		16.7 ± 4.5		5.0 ± 4.1	16.9 ± 8.9		23.2 ± 8.2
					on a GFD	1.02 ± 0.2	34.7 ± 12.3		17.3 ± 3.1		6.2 ± 4.2	19.4 ± 8.0		26.0 ± 9.3
Gallardo et al., 2008 [30] *	children	N/A	DXA	10	before a GFD		significantly increased after a GFD		significantly increased after a GFD		did not change significantly after a GFD			significantly increased after a GFD
					on a GFD	≥1
Suárez-González et al., 2020 [31]	children	N/A	BIA	72	before a GFD			Z-score: 0.2 ± 1.1				20.4 ± 9.3			79.5 ± 9.4
					on a GFD	2 (0.7–11.5)		Z-score: 0.1 ± 0.1				16.9 ± 8.6			83.1 ± 8.4
Capristo et al., 2009 [32]	adults	N/A	DXA	26	before a GFD		60.3 ± 3.8		22.1 ± 1.2		14.6 ± 2.6			45.7 ± 4
					on a GFD	1.2 ± 0.1	63.0 ± 3.5		23.1 ± 1.3		16.7 ± 2.7			46.2 ± 3.9
Newnham et al., 2016 [33]	adults	N/A	DXA	52	before a GFD		68.1 ± 12.3		24.1 ± 3.5		20.4 ± 5.9	31.4 ± 8.3		46.5 ± 8.5
					on a GFD	1	71.1 ± 14.4		25.0 ± 4.2		24.7 ± 10.3	34 ± 8.8		46.4 ± 9.4
Smecuol et al., 1997 [34]	adults	N/A	DXA	25	before a GFD		48.6 ± 2.2		19.5 ± 0.7		11.8 ± 1.5			33.4 ± 1.4
					on a GFD	3.1 (2.2–4.1)	55.7 ± 2.3		22.2 ± 0.7		18.2 ± 1.7			35.3 ± 1
Rocco et al., 2014 [35] *	adults	N/A	BIA	15	before a GFD						19.9			50.2
					on a GFD	≥1			did not change significantly after a GFD		did not change significantly after a GFD			significantly decreased after a GFD
Wiech et al., 2018 [36]	children	N/A	BIA	22	before a GFD		32.4 ± 15.7		16.8 ± 2.8		7.2 ± 4.6	22.1 ± 6.5		25.2 ± 12.2	78.0 ± 6.5
					on a GFD	1.4	36.0 ± 14.1		17.1 ± 2.1		7.4 ± 3.8	21.2 ± 6.9		28.6 ± 11.9	78.8 ± 6.9
	Celiac patients on a gluten-free diet for at least one year vs. non-celiac control subjects
Tsiountsioura et al., 2014 [9]	children	-	BIA	26	on a GFD			Z-score: −0.0 ± 1.2		Z-score: 0.1 ± 1.1			Z-score: 0.3 ± 1.2			Z-score: 0 ± 1.0
				54	control			Z-score: 0.2 ± 1.1		Z-score: 0.4 ± 1.5			Z-score: 0.4 ± 1.3			Z-score: 0.2 ± 1.2
Capristo et al., 2000 [10]	adults	age, height	ID	39	on a GFD	1.0 ± 0.0	61.4 ± 5.7				13.3 ± 2.7	21.9 ± 3.5		48.1 ± 4.9	78.2 ± 3.4
				63	control		67.0 ± 6.6				16.9 ± 3.0	25.4 ± 4.0		50.2 ± 6.2	74.8 ± 4.2
Bardella et al., 2000 [11]	adults	age, gender	DXA	71	on a GFD	≥2	59.4 ± 10.8		21.2 ± 2.8			20.4 ± 6.4		43.5 ± 9.0
				142	control		62.8 ± 10.8		22.7 ± 4.0			24.5 ± 7.0		45.1 ± 8.3
Bassil et al., 2017 [13] *	adults	age, gender	DXA	19	on a GFD		63.3 ± 3.0		22.2 ± 0.8		17.8 ± 2.0
				32	control		25.7 ± 0.7		25.7 ± 0.7		24.7 ± 1.9
Bodé et al., 1991 [14]	adults	age	STM	22	on a GFD	8.1 ± 6.0			significantly lower in CD than in control subjects		significantly lower in CD than in control subjects			significantly higher in CD than in control subjects
				-	control
Capristo et al., 1997 [15]	adults	age, gender	BIA	18	on a GFD	3.7 (1–6.3)	55.6 (40.0–66.0)		20.2 (14.9–25.8)		11.7 (5.3–24.4)	20.9 (9.7–37.0)		42.9 (31.5–56.4)	78.7 (63.0–90.3)
				20	control		66.4 (57.0–76.0)		23.6 (19.4–26.0)		17.4 (9.88–24.2)	26.7 (14.2–35.9)		49.6 (36.7–60.9)	74.2 (64.1–85.8)
Ballestero-Fernández et al., 2019 [16]	children	age, gender	STM	70	on a GFD	≥1	34.8 ± 4.9		17.2 ± 0.7			17 ± 2.0
				67	control		38 ± 4.8		18.5 ± 1.2			17.7 ± 2.1
Barera et al., 2000 [26]	adults	age, gender	DXA	23	on a GFD	10.6 ± 4.5	54.2 ± 10.9		21.4 ± 3.2		10.8 ± 6	22.1 ± 10.3		39.4 ± 10.8
				25	control		58.5 ± 11.8		20.9 ± 2.7		13.8 ± 7.1	24.4 ± 10.2		41.4 ± 9.8
Björck et al., 2017 [27]	children	age, gender, HLA-DQ	DXA	30	on a GFD	6.9 ± 1.1	41.6 ± 10.2		18.8 ± 3.4		13.1 ± 6.4			27 ± 4.8
				60	control		41.7 ± 10.1		18.4 ± 3.4		12.7 ± 6.3			27.5 ± 4.7
Carbone et al., 2003 [37]	adults	age, gender	DXA	11	on a GFD	0.8–13	55.3 ± 10.4				17.8 ± 6.4			34.8 ± 6.9
				11	control		69.6 ± 13.6				25.9 ± 13.2			41.5 ± 6.9
	children		DXA	48	on a GFD	0.8–13	50.5 ± 11.8				15.6 ± 7.0			32.5 ± 8.5
				30	control		62.2 ± 12				12.9 ± 8.8			46.3 ± 12.5
De Lorenzo et al., 1999 [38]	children	age, gender	DXA	43	on a GFD	1 ± 0.3	48.8 ± 11.4		19.8 ± 3.1		15 ± 6.8			31.6 ± 8.1
				30	control		62.2 ± 12.0		21.6 ± 3.0		12.9 ± 8.8			46.3 ± 12.5
			BIA	43	on a GFD	1 ± 0.3	48.8 ± 11.4		19.8 ± 3.1		19.3 ± 8.8			32.4 ± 8.1
				30	control		62.2 ± 12.0		21.6 ± 3.0		18.9 ± 9.4			45.4 ± 10.2
Barone et al., 2015 [39]	adults	age, gender, social status	DXA	39	on a GFD	2.2 ± 0.9						29.9 ± 7.8
				39	control							29.8 ± 7.8
Nunes-Silva et al., 2017 [40]	adults	age, gender BMI	BIA	15	on a GFD	6–12			22.9 ± 3.6			37.3 ± 4.4
				15	control				23.1 ± 2.7			32.7 ± 10.6
Ballestero-Fernández et al., 2021 [41]	adults	age, gender	STM	64	on a GFD	≥1	66 ± 5.4		22.8 ± 1.6			30.5 ± 3.6
				74	control		64.3 ± 4.1		23.5 ± 1.6			29.8 ± 3.2
Nestares et al., 2021 [42]	children	age, gender	DXA	41	on a GFD	≥1.5	significantly lower in CD than in control subjects		no significant difference between CD and control subjects		no significant difference between CD and control subjects			significantly lower in CD than in control subjects
				40	control
Silva et al., 2014 [43]	children	age, gender	BIA	31	on a GFD	≥1	no significant difference between CD and control subjects		no significant difference between CD and control subjects		no significant difference between CD and control subjects			no significant difference between CD and control subjects
				31	control

* presented: Conference abstracts; studies with underline are included in meta-analyses; BIA: Bioimpedance analysis; DXA: Dual-energy X-ray absorptiometry; ID: Isotopic dilution; STM: Skinfold thickness measurement; GFD: Gluten-free diet; N/A: Not applicable; values are reported in mean and standard deviation: $\overline{x}$ ± SD; or mean and range: $\overline{x}$(range).