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Evidence found and GRADE certainty

3,372 questions · 3,874 findings · 666 reviews

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No studies found 431 · 11.1%GRADE not reported 783 · 20.2%Very low 995 · 25.7%Low 909 · 23.5%Moderate 596 · 15.4%High 160 · 4.1%

Sugar consumption (higher sugar intake) vs No sugar consumption (lower/no intake)

Early childhood caries (ECC) · Preschool children (<6 years)

Higher sugar consumption is associated with early childhood caries in children under 6 years: pooled OR 1.59 (95% CI 1.50 to 1.68) from 9 cohort studies with no heterogeneity (I2=0%); the body of evidence was not GRADE-rated (ungraded).

1 finding from 1 review

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Risk of fragility fractures · Females (all ages)

In females, fragility-fracture risk was U-shaped: lowest ~0.4 mg/L, rising above 0.9 mg/L (RR 0.84 at 0.34, 1.00 at 0.9, 1.13 at 1.1 mg/L vs null); ungraded.

3 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females: drinking-water fluoride 1.1 mg/L vs null
    RR 1.13 [0.93, 1.37]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females: drinking-water fluoride 0.34 mg/L vs null
    RR 0.84 [0.67, 1.07]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females: drinking-water fluoride 0.9 mg/L vs null
    RR 1.00 [0.79, 1.27]
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Lumbar spine bone mineral density (BMD) · Females (all ages)

In females (low-to-moderate risk-of-bias studies), spine BMD rose then plateaued ~0.5 mg/L: MD 0.02 g/cm2 (95% CI -0.02-0.07) at 0.20 mg/L and 0.06 (-0.01-0.12) across 0.7-2.35 mg/L vs null; ungraded.

2 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females, low-to-moderate risk-of-bias studies: 0.7-2.35 mg/L vs null
    MD 0.06 [-0.01, 0.12]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females, low-to-moderate risk-of-bias studies: 0.20 mg/L vs null
    MD 0.02 [-0.02, 0.07]
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Risk of fragility fractures · Females aged over 50 years

In females over 50, fragility-fracture risk rose steeply from ~0.5 mg/L: RR 0.98 at 0.25, 1.00 at 0.45, and 1.26 (95% CI 1.10-1.46) at 1.0 mg/L drinking-water fluoride vs null; ungraded.

3 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females over 50 years: drinking-water fluoride 0.45 mg/L vs null
    RR 1.00 [0.80, 1.24]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females over 50 years: drinking-water fluoride 0.25 mg/L vs null
    RR 0.98 [0.83, 1.14]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females over 50 years: drinking-water fluoride 1.0 mg/L vs null
    RR 1.26 [1.10, 1.46]
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Hip/femoral bone mineral density (BMD) · general population

Hip BMD increased with fluoride in both sexes (linearly in males, non-linearly above ~1.2 mg/L in females); no numeric MD reported in text for the main analysis; ungraded.

1 finding from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Both sexes, main dose-response
    Hip BMD increased in both sexes, linearly in males and non-linearly (starting above 1.2 mg/L) in females (no numeric MD reported in text for main analysis)
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Hip/femoral bone mineral density (BMD) · Females (all ages)

In females (low-to-moderate risk-of-bias studies), hip BMD rose monotonically above ~0.9 mg/L: MD 0.04 g/cm2 (95% CI -0.03-0.12) up to ~2.3 mg/L and 0.09 (-0.09-0.27) at 4.0 mg/L vs null; ungraded.

2 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females, low-to-moderate risk-of-bias studies: up to ~2.3 mg/L vs null
    MD 0.04 [-0.03, 0.12]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females, low-to-moderate risk-of-bias studies: 4.0 mg/L vs null
    MD 0.09 [-0.09, 0.27]
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Wrist fractures · general population

Wrist-fracture risk declined nearly linearly with increasing fluoride: RR 1.00 at 0.01 mg/L to 0.84 at 1.5 mg/L drinking-water fluoride vs null; ungraded.

2 findings from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Drinking-water fluoride 1.5 mg/L vs null
    RR 0.84 [0.43, 1.65]
    Studies not reported
    GRADE not reported
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Drinking-water fluoride 0.01 mg/L vs null
    RR 1.00 [0.99, 1.01]
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Hip Fracture · general population

Overall hip-fracture risk showed little association with drinking-water fluoride and a nearly flat dose-response curve (narrow CI); no numeric RR reported in text; ungraded.

1 finding from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Overall dose-response (0 to highest exposure)
    Curve indicated little association and was nearly flat, with a comparatively narrow 95% confidence band (no numeric RR reported in text)
    Studies not reported
    GRADE not reported

Higher drinking-water fluoride exposure vs Null / lowest drinking-water fluoride exposure (reference)

Lumbar spine bone mineral density (BMD) · Females aged over 50 years

In females over 50, spine BMD showed an inverted U-shaped curve with a downward trend beginning at lower fluoride concentrations than in the overall analysis; no numeric MD reported in text; ungraded.

1 finding from 1 review
  • The association of fluoride exposure with bone density and fracture risk: a dose-response meta-analysis. 2025 All outcomes
    Long-term / lifetime fluoride exposure · General population; 37 observational studies (1944-2024), predominantly North America (USA, Canada) and Northern Europe (Finland, Sweden), plus UK, Poland, Italy, Germany, China, Taiwan, South Korea, Ethiopia; exposure mainly community drinking-water fluoride · Females >50, spine BMD dose-response
    Inverted U-shaped curve with a downward trend starting at lower fluoride concentrations than the overall analysis (no numeric MD reported in text)
    Studies not reported
    GRADE not reported

Highest BMI category (overweight/obese) vs Lowest BMI category (normal weight/underweight)

Early childhood caries (ECC) · Children (approx. 4-18 years)

In the Region: Asian countries subgroup, the BMI (highest vs lowest)-childhood caries association was significant (OR 1.70, 95% CI 1.25 to 2.32; ungraded).

17 findings from 1 review
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