. 2023 May 27;23:986. doi: 10.1186/s12889-023-15884-5

Table 4.

Identified studies^a with data enabling estimation of the dose response between sugars and dental caries

Author (year)/ Country	Objectives	Study population, sugars exposure and dental outcome	Data on dose response	Quality appraisal
Cohort Studies
Rugg-Gunn et al. (1984;1987) [107, 108] England	Cohort study To study dietary habits and the development of dental caries over the same period (2 years)	Children (n = 405) aged 12–15 years. Total sugars intake. DMFS increment over 2 years	Sugar intake related to fissure caries increment after adjusting for confounders. Each 30 g/day increased DMFS by 0.36 (95% CI: 0.07, 0.80) over 2-year follow up	Quality appraised by Turuk et al. [12] using OHAT: Tier 2-Probably high RoB Quality of studies not assessed by SACN/ Moynihan and Kelly [3]
Burt et al. (1988; 1994) [105, 111] Szpunar et al. (1995) [106] USA	Cohort study To investigate the relationship between total sugars intake and development of dental caries over 3 years. The study also aimed to relate sugars consumption to the probability of experiencing caries increment	Children (n =) 499 initially aged 10–15 years in Michigan USA. Living in rural non-fluoridated areas Total sugars DMFS over 3 years	Each + 5 g sugars led to a 1% increase in the probability of developing caries over 3-year follow up Higher sugar (% EI and g/d) increased probability of caries on all surfaces but only a higher % EI from sugars significantly increased probability of pit, fissure and aproximal caries	Quality appraised by Turuk et al. [12] using OHAT: Tier 1, probably low RoB Quality of studies not assessed by SACN/ Moynihan and Kelly [3]
Bernabe et al. (2016) [104] Finland	Cohort study Explored the shape of the association of frequency and amount of sugars intake with caries in adults, 2) the relative contribution of frequency and amount of sugars intake to caries levels, and 3) whether the association of frequency and amount of sugars consumption with caries varies according to exposure to fluoride	Finish adults (n = 1702) followed up 11 years. Total sugars intake	A linear dose response relationship observed between sugars intake from 13.7 g/d (~ 2% E) to 442 g/d and caries increment. For every 10-g/d sugars intake, DMFT increased by 0.09 (95% CI: 0.02,0.15), p = 0.14	Quality appraised by Turuk et al. [12] and Moores et al. [4] using OHAT: Tier 1, probably low RoB
Cross sectional studies
Saw et al. (2012) [116] Malaysia	Cross sectional study To investigate the dietary intake of adults in dental clinic and to evaluate their dental caries experience using DMFT scores. The relationship between total dietary intake and dental caries experience was also investigated	Adults (n = 168) 20–59 years Sugars (not defined) g/day and % EI) DMFT by WHO methods	NS correlation between sugars and DMFT index (r = 0.055, P = 0.476). Correlations assessed using Spearman’s rho correlation test and Pearson correlation test. No apparent adjustment for confounders	Quality appraised by Moores et al. [4] using OHAT: Tier 3, definitely high RoB
Chi et al. (2015) [114] USA (Alaska)	Cross sectional study Evaluated the feasibility of collecting hair samples from Yupik children and tested the association between the hair biomarker-based measure of added sugar intake and tooth decay	Native Alaskan Children Added sugars assessed using biomarker of intake % carious surfaces assessed	Age-adjusted linear regression: 40 g/day increase in added sugars intake associated with a 6.4% absolute increase in the proportion of carious tooth surfaces (95% CI: 1.2% to 11.6%; P = 0.02) Log-linear regression model: 40 g/day increase in added sugars associated with a 24.2% relative increase in the proportion of carious tooth surfaces (95% CI: 10.6% to 39.4%; P < 0.01)	Quality appraised by Moores et al. [4] using OHAT: Tier 2, Probably high RoB
Mitrakul et al. (2016) [117] Thailand	Cross sectional study To examine the association between dental caries and 2 factors: BMI and diet	Children aged 6–12 years (n = 100) Total sugars intake DMFT	Correlation between total sugars and DMFT score: R = -0.128, P = 0.205. Graphical data show total sugars intake ranged from 0-140 g/day (reported as mg/day, but this was assumed to be g/day)	Quality appraised by Moores et al. [4] using OHAT: Tier 3, definitely high RoB
Rosier et al. (2017) [113] Netherlands	Cross sectional study To comprehensively describe the early stages of caries in a healthy young adult population free of cavities and the relationship with behavioural caries risk factors e.g., diet, oral hygiene	Adults (n = 268) Total sugars % EI Enamel caries (ICDAS 1–6)	Correlation coefficient for enamel caries and percent energy from sugars was 0.21 (P < 0.01) and for any caries was 0.19 (P < 0.01)	Quality appraised by Moores et al. [4] using OHAT: Tier 2, Probably high RoB
Barrington et al. (2019) [112] Australia	Cross sectional study investigating association of overweight/obesity, dental caries experience and diet in a nationally representative sample of Australian adults	15–60 years old (n = 4170) Added sugars intake DMFT from National Survey of Adult Oral Health	Positive association between dental caries experience (DMFT), and sugars consumption. Added sugars and total sugars were significantly associated with decayed and missing teeth in adults. Multivariate regression Added sugars • DMFT, 1.0002 (95% CI: 0.999, 1.004), P = 0.145 • D, 1.01 (95% CI: 1.00,1.02), P < 0.05 • M, 1.01 (95% CI: 1.00, 1.01), P < 0.001 • F, 0.999 (95% CI: 0.996, 1.003), P = 0.744 Total sugars • DMFT, 1.0003 (95% CI: 0.99, 1.00), P = 0.254 • D, 1.003 (95% CI: 1.001, 1.003), P < 0.001 • M, 1.001 (95% CI: 1.0004, 1.002), P < 0.05 • F, 0.999 (95% CI: 0.999, 1.001), P = 0.659	Quality appraised by Moores et al. 2022 using OHAT: Tier 2, Probably high RoB
Ecological studies
Olczak-Kowalczyk et al. (2016) [115] Poland	Ecological study To assess the relationship between dental caries incidence and general consumption of sucrose in 12-year-old children	Children aged 12 (no further description) Sucrose intake per capita	An increase in sucrose intake by 1 kg/year resulted in an increase in caries frequency by almost 0.92% and an increase in DMFT value by over 0.2%	Quality appraised by Moores et al. [4] using OHAT: Tier 2, Probably high RoB

Author (year)/
Country

Objectives

Study population, sugars exposure and dental outcome

Data on dose response

Quality appraisal

Cohort Studies

Rugg-Gunn et al. (1984;1987) [107, 108]

England

Cohort study

To study dietary habits and the development of dental caries over the same period (2 years)

Children (n = 405) aged 12–15 years. Total sugars intake. DMFS increment over 2 years

Sugar intake related to fissure caries increment after adjusting for confounders. Each 30 g/day increased DMFS by 0.36 (95% CI: 0.07, 0.80) over 2-year follow up

Quality appraised by Turuk et al. [12] using OHAT: Tier 2-Probably high RoB

Quality of studies not assessed by SACN/ Moynihan and Kelly [3]

Burt et al. (1988; 1994) [105, 111]

Szpunar et al. (1995) [106]

USA

Cohort study

To investigate the relationship between total sugars intake and development of dental caries over 3 years. The study also aimed to relate sugars consumption to the probability of experiencing caries increment

Children (n =) 499 initially aged 10–15 years in Michigan USA. Living in rural non-fluoridated areas

Total sugars

DMFS over 3 years

Each + 5 g sugars led to a 1% increase in the probability of developing caries over 3-year follow up

Higher sugar (% EI and g/d) increased probability of caries on all surfaces but only a higher % EI from sugars significantly increased probability of pit, fissure and aproximal caries

Quality appraised by Turuk et al. [12] using OHAT: Tier 1, probably low RoB

Quality of studies not assessed by SACN/ Moynihan and Kelly [3]

Bernabe et al. (2016) [104]

Finland

Cohort study

Explored the shape of the association of frequency and amount of sugars intake with caries in adults, 2) the relative contribution of frequency and amount of sugars intake to caries levels, and 3) whether the association of frequency and amount of sugars consumption with caries varies according to exposure to fluoride

Finish adults (n = 1702) followed up 11 years. Total sugars intake

A linear dose response relationship observed between sugars intake from 13.7 g/d (~ 2% E) to 442 g/d and caries increment. For every 10-g/d sugars intake, DMFT increased by 0.09 (95% CI: 0.02,0.15), p = 0.14

Quality appraised by Turuk et al. [12] and Moores et al. [4] using OHAT: Tier 1, probably low RoB

Cross sectional studies

Saw et al. (2012) [116]

Malaysia

Cross sectional study

To investigate the dietary intake of adults in dental clinic and to evaluate their dental caries experience using DMFT scores. The relationship between total dietary intake and dental caries experience was also investigated

Adults (n = 168) 20–59 years

Sugars (not defined) g/day and % EI)

DMFT by WHO methods

NS correlation between sugars and DMFT index (r = 0.055, P = 0.476). Correlations assessed using Spearman’s rho correlation test and Pearson correlation test. No apparent adjustment for confounders

Quality appraised by Moores et al. [4] using OHAT: Tier 3, definitely high RoB

Chi et al. (2015) [114]

USA (Alaska)

Cross sectional study

Evaluated the feasibility of collecting hair samples from Yupik children and tested the association between the hair biomarker-based measure of added sugar intake and tooth decay

Native Alaskan Children

Added sugars assessed using biomarker of intake

% carious surfaces assessed

Age-adjusted linear regression: 40 g/day increase in added sugars intake associated with a 6.4% absolute increase in the proportion of carious tooth surfaces (95% CI: 1.2% to 11.6%; P = 0.02)

Log-linear regression model: 40 g/day increase in added sugars associated with a 24.2% relative increase in the proportion of carious tooth surfaces (95% CI: 10.6% to 39.4%; P < 0.01)

Quality appraised by Moores et al. [4] using OHAT: Tier 2, Probably high RoB

Mitrakul et al. (2016) [117]

Thailand

Cross sectional study

To examine the association between dental caries and 2 factors: BMI and diet

Children aged 6–12 years (n = 100)

Total sugars intake

DMFT

Correlation between total sugars and DMFT score: R = -0.128, P = 0.205. Graphical data show total sugars intake ranged from 0-140 g/day (reported as mg/day, but this was assumed to be g/day)

Quality appraised by Moores et al. [4] using OHAT: Tier 3, definitely high RoB

Rosier et al. (2017) [113]

Netherlands

Cross sectional study

To comprehensively describe the early stages of caries in a healthy young adult population free of cavities and the relationship with behavioural caries risk factors e.g., diet, oral hygiene

Adults (n = 268)

Total sugars % EI

Enamel caries (ICDAS 1–6)

Correlation coefficient for enamel caries and percent energy from sugars was 0.21 (P < 0.01) and for any caries was 0.19 (P < 0.01)

Quality appraised by Moores et al. [4] using OHAT: Tier 2, Probably high RoB

Barrington et al. (2019) [112]

Australia

Cross sectional study investigating association of overweight/obesity, dental caries experience and diet in a nationally representative sample of Australian adults

15–60 years old (n = 4170)

Added sugars intake

DMFT from National Survey of Adult Oral Health

Positive association between dental caries experience (DMFT), and sugars consumption. Added sugars and total sugars were significantly associated with decayed and missing teeth in adults. Multivariate regression

Added sugars

• DMFT, 1.0002 (95% CI: 0.999, 1.004), P = 0.145

• D, 1.01 (95% CI: 1.00,1.02), P < 0.05

• M, 1.01 (95% CI: 1.00, 1.01), P < 0.001

• F, 0.999 (95% CI: 0.996, 1.003), P = 0.744

Total sugars

• DMFT, 1.0003 (95% CI: 0.99, 1.00), P = 0.254

• D, 1.003 (95% CI: 1.001, 1.003), P < 0.001

• M, 1.001 (95% CI: 1.0004, 1.002), P < 0.05

• F, 0.999 (95% CI: 0.999, 1.001), P = 0.659

Quality appraised by Moores et al. 2022 using OHAT: Tier 2, Probably high RoB

Ecological studies

Olczak-Kowalczyk et al. (2016) [115]

Poland

Ecological study

To assess the relationship between dental caries incidence and general consumption of sucrose in 12-year-old children

Children aged 12 (no further description)

Sucrose intake per capita

An increase in sucrose intake by 1 kg/year resulted in an increase in caries frequency by almost 0.92% and an increase in DMFT value by over 0.2%

Quality appraised by Moores et al. [4] using OHAT: Tier 2, Probably high RoB

CI Confidence interval, D3MDT Decayed (into dentine) missing and filled permanent teeth, DMFS Decayed missing and filled permanent tooth surfaces, EI Energy intake, ICDAS International Caries Detection and Assessment System, OR Odds ratio, RoB Risk of Bias. OHAT https://ntp.niehs.nih.gov/whatwestudy/assessments/noncancer/riskbias/index.html, OR odds ratio

^a Original studies identified in systematic reviews addressing Question 3