Is sucralose safe during pregnancy?

Regulators say yes, within the acceptable daily intake, and that answer rests on animal studies. No randomized trial has given sucralose to pregnant women. In its 2026 re-evaluation the European Food Safety Authority kept the acceptable daily intake at 15 mg per kg of body weight a day, and for reproductive and developmental toxicity it had only animal data, with human data treated as missing. What human studies show is narrower. Sucralose crosses the placenta and passes into breast milk. One Chilean cohort of 1,472 pregnant women linked sucralose use to 44 percent higher odds of gestational diabetes. It is an observational finding, and no other cohort we found estimated sucralose on its own.

Unsettled. The answer is unsettled because the evidence that would settle it does not exist. There is no trial in pregnancy and no systematic review of sucralose in pregnancy. The regulators' verdict comes from animal studies, and the human data are a handful of observational studies, most of them small or unable to separate sucralose from other sweeteners.

What the trials found

No trial in pregnancy

We found no randomized trial that tested sucralose in pregnant women. The strongest general evidence is a 2019 systematic review with meta-analyses of 56 studies in healthy adults and children. It found no differences for most health outcomes between people who used non-sugar sweeteners and those who did not, on very low to moderate certainty evidence. It did not analyze pregnancy, and it did not look at sucralose on its own.

Sweeteners are common in pregnancy. In the ROLO trial of 571 pregnant women in Ireland, one third ate or drank low-calorie sweeteners in each trimester. That trial measured intake and did not test whether sweeteners changed any outcome. In a survey of 601 pregnant women in the two main cities of Chile, 95.6 percent consumed sucralose, and none exceeded the acceptable daily intake of any sweetener. Chile labels sugary foods heavily and has replaced a lot of sugar with sweeteners, so that share does not carry over to other countries.

Sucralose reaches the baby

In a Danish study of 28 women before a planned cesarean section, 19 drank an artificially sweetened drink and 9 avoided sweeteners. Sucralose levels in fetal blood rose with the mother's levels, with an adjusted coefficient of 0.44 (95% CI 0.33 to 0.55). The study shows that the fetus is exposed. It did not measure harm, it was small, and it stopped earlier than planned.

After birth, sucralose passes into breast milk. In 34 nursing mothers who drank one diet soda, the median peak in milk was 8.1 ng/mL, and one mother with extremely high levels stretched the range to 7,387.9 ng/mL. In 21 percent of them sucralose was already in the milk before the drink. In a separate study of 20 breastfeeding women, saccharin, sucralose or acesulfame-potassium were found in the milk of 65 percent. Neither study measured any effect on the infants.

Gestational diabetes

In the Chilean cohort of 1,472 pregnant women in primary care, sucralose use was linked to 44 percent higher odds of gestational diabetes after adjustment (odds ratio 1.44, 95% CI 1.06 to 1.95). Any non-nutritive sweetener carried an odds ratio of 1.58 (95% CI 1.10 to 2.26). This is the only cohort we found that estimated sucralose separately. It is observational, and residual confounding is possible. Women who already have a higher risk of diabetes may be the ones choosing sweeteners.

The baby's weight

In a Mexican study of 292 newborns, babies of mothers who took more than 36 mg of sucralose a day were heavier at birth than babies of light users, 3.2 against 6.2 lb (2.8 kg) (p = 0.0005). Intake was grouped by questionnaire and checked in the mothers' blood. Sucralose was undetectable in cord blood in that study, which sits awkwardly beside the Danish finding. The study is small, cross-sectional and observational.

Two large cohorts counted diet drinks of any kind. In the Canadian CHILD cohort of 3,033 mothers and infants, daily artificially sweetened drinks in pregnancy were linked to twice the odds of overweight at 1 year (odds ratio 2.19, 95% CI 1.23 to 3.88). In the Danish National Birth Cohort, children of mothers who drank at least one a day had 26 percent higher odds of overweight at 18 years (odds ratio 1.26, 95% CI 1.12 to 1.42). Denmark collected those data in 1996 to 2002, and neither cohort separated sucralose from other sweeteners.

Mice

Animal data suggest a possible signal for the heart. In a 2026 experiment, pregnant mice given sucralose in drinking water in early pregnancy, at a dose the authors put close to the human acceptable intake, more often had litters with heart defects, 10 of 14 against 2 of 14 in controls. It is one experiment in 28 mice, it has not been repeated, and mouse findings do not transfer to people directly.

For the rest of what is known about sucralose, see the sucralose page.

Who should be careful

Not for everyone. If you are pregnant, the honest position is that EFSA judged sucralose safe within the acceptable daily intake with no human data on pregnancy outcomes, only animal studies. It reaches the fetus, it reaches breast milk, and the one animal experiment aimed at early pregnancy found more heart defects. None of that proves harm in people. It does mean the reassurance is weaker in pregnancy than for adults in general.

EFSA holds the acceptable daily intake at 15 mg/kg a day and found that intakes from current uses sit below it. In Chile, where sucralose is in most sweetened foods, no pregnant woman in the survey above went over the limit. Neither EFSA nor the US Food and Drug Administration says anything specific about pregnancy in the statements we read.

What expert bodies say

The European Food Safety Authority, in its 2026 re-evaluation, concluded there was no need to change the acceptable daily intake of 15 mg/kg a day. For reproductive, maternal and developmental toxicity it had animal data only, and it handled the human side as missing data.

The US Food and Drug Administration says its review of sucralose covered more than 110 studies, including studies on the reproductive and nervous systems. Its position is that the sweeteners it has authorized, sucralose among them, are safe for the general population under the approved conditions of use. Pregnant women are not named separately.

How we searched

What would change this answer

• A randomized trial of cutting sweeteners in pregnancy. The SweetPea trial, registered as NCT06548828, tests reducing non-nutritive sweeteners in pregnancy and breastfeeding. A trial that gives sucralose itself to pregnant women does not exist.
• A cohort that measures sucralose separately from other sweeteners and reports absolute rates of gestational diabetes and birth weight, so a relative link can be turned into a number of extra cases. A Mexican study of perinatal sweetener exposure and infant weight, NCT03972176, is registered.
• A repeat of the mouse heart experiment in another laboratory, and human data on reproductive and developmental outcomes that EFSA could use instead of treating them as missing.

Sources

1. ev-sucg-01 · Meta-analysis or systematic review · systematic review and meta-analyses of randomized and non-randomized controlled trials and observational studies · n = 56 studies (35 observational)
   Most health outcomes did not seem to have differences between the NSS exposed and unexposed groups.
   
   Who: generally healthy or overweight/obese adults and children; NSS within the acceptable daily intake for at least 7 days
   Effect: most outcomes no difference between NSS exposed and unexposed; very low to moderate certainty
   Certainty: Not about pregnant women and not about sucralose separately; the closest synthesis. Pregnancy was not analyzed.
   BMJ, 2019 · checked 2026-10-07 · we read the abstract
2. ev-sucg-02 · Observational data · secondary analysis of a randomized controlled trial · n = 571
   One-third of all pregnant women consumed LCS across each trimester of pregnancy.
   
   Who: pregnant women randomized to low-GI dietary advice or usual antenatal care; 3-day food diary each trimester
   Effect: about one third consumers each trimester
   Certainty: About intake, not consequences; sweeteners not distinguished.
   Eur J Clin Nutr, 2022 · checked 2026-10-07 · we read the abstract
3. ev-sucg-03 · Observational data · secondary analysis of a prospective cohort · n = 1472
   The adjusted model showed a significant association between the consumption of any NNS and sucralose and the risk of GDM (OR for any NNS = 1.58; 95% CI: 1.10-2.26; P = 0.014; OR sucralose = 1.44; 95% CI 1.06-1.95; P = 0.020).
   
   Who: pregnant women in primary care, Puente Alto, Chile (CHiMINCs-II); 24-h recalls
   Effect: sucralose OR 1.44 (95% CI 1.06 to 1.95); any NNS OR 1.58 (1.10 to 2.26)
   Certainty: The only cohort with a separate estimate for sucralose specifically; observational, residual confounding possible.
   Nutrition, 2024 · checked 2026-10-07 · we read the abstract
4. ev-sucg-04 · Observational data · cross-sectional, prospective study · n = 292
   Conversely, infants born from mothers who heavily consumed sucralose displayed a significant increase in birth weight compared to that found in newborns from mothers who lightly ingested sucralose (3.2 ± 0.6 vs. 2.8 ± 0.1, p = 0.0005) (Table 1).
   
   Who: mother-newborn pairs, Mexico; heavy users >36 mg sucralose/day (more than 3 packets) vs light users <60 mg/week; intake by FFQ, confirmed by serum HPLC
   Effect: birth weight 3.2 +/- 0.6 vs 2.8 +/- 0.1 kg (p = 0.0005); cord insulin higher; sucralose undetectable in cord blood
   Certainty: Small observational study; groups by questionnaire; inflammation markers are surrogate.
   Biomedicines, 2023, Newborns from Mothers Who Intensely Consumed Sucralose during Pregnancy Are Heavier · checked 2026-10-07 · we read the fulltext
5. ev-sucg-05 · Observational data · non-randomized clinical pharmacokinetic study · n = 28 (19 intervention, 9 controls)
   We found that fetal plasma concentrations had a significant, positive, linear dependency on the maternal plasma concentrations of all four artificial sweeteners, with adjusted coefficients of 0.49 (CI: 0.28–0.70) for acesulfame, 0.72 (CI: 0.48–0.95) for cyclamate, 0.51 (CI: 0.38–0.67) for saccharin, and 0.44 (0.33–0.55) for sucralose (Figure 2 and Table 3).
   
   Who: pregnant women before planned cesarean section, Denmark; intervention group drank an artificially sweetened drink, controls avoided sweeteners
   Effect: fetal vs maternal plasma sucralose adjusted coefficient 0.44 (0.33 to 0.55); fetal/maternal ratio 0.57 (0.42 to 0.73)
   Certainty: Shows fetal exposure, not harm; small sample, stopped earlier than planned.
   Nutrients, 2023, Transplacental Transport of Artificial Sweeteners · checked 2026-10-07 · we read the fulltext
6. ev-sucg-06 · Observational data · pharmacokinetic study · n = 34
   Due to one mother having extremely high concentrations, peak sucralose concentrations following ingestion of diet soda ranged from 4.0–7,387.9 ng/mL (median peak 8.1 ng/mL) and the AUC ranged from 526.1 – 2,337,351 ng/mL (median AUC 1244.2 ng/mL).
   
   Who: lactating mothers, normal weight (14) and obese (20), milk sampled over 6 hours after a diet soda
   Effect: peak milk sucralose 4.0 to 7,387.9 ng/mL (median 8.1 ng/mL); 21% had sucralose in milk before the drink
   Certainty: About lactation, not pregnancy; clinical consequences for infants were not measured.
   Journal of Pediatric Gastroenterology and Nutrition, 2018, Pharmacokinetics of Sucralose and Acesulfame-Potassium in Breast Milk Following Ingestion of Diet Soda · checked 2026-10-07 · we read the fulltext
7. ev-sucg-07 · Observational data · cross-sectional sampling study · n = 20
   Saccharin, sucralose, and acesulfame-potassium were present in breast milk of 65% of participants, most of whom reported NNS intake during the day prior to donating a breast milk sample.
   
   Who: lactating women recruited irrespective of sweetener use, USA (NIH)
   Effect: NNS detected in 65% of milk samples; aspartame not detected
   Certainty: Small sample; outcomes for the child were not measured.
   Journal of Toxicology and Environmental Health Part A, 2015, Nonnutritive Sweeteners in Breast Milk · checked 2026-10-07 · we read the fulltext
8. ev-sucg-08 · Observational data · cross-sectional study · n = 601
   The most consumed sweetener was sucralose (95.6%), followed by acesulfame k (80.6%), stevia (78.3%), aspartame (75.1%), saccharin (14.8%), and cyclamate (10%). ... No pregnant woman in the sample exceeded the acceptable daily intake and there were no differences in sweetener consumption by trimester of pregnancy or by socioeconomic level.
   
   Who: pregnant women in the two main cities of Chile
   Effect: sucralose consumers 95.6%; no woman above ADI; averages under 5% of ADI except stevia
   Certainty: A country with mandatory labeling and mass sugar replacement; not transferable to everyone.
   Nutr Hosp, 2019 · checked 2026-10-07 · we read the abstract
9. ev-sucg-09 · Observational data · longitudinal cohort · n = 72,821 women with FFQ
   We found increased odds of overweight in 7-, 11-, 14- and 18-year-old offspring whose mothers reported drinking ≥ 1 artificially sweetened beverage daily during pregnancy compared with no consumption (18 years: adjusted OR 1·26 (95 % CI 1·12, 1·42)).
   
   Who: Danish National Birth Cohort 1996-2002; maternal FFQ in pregnancy; offspring followed to 18 years
   Effect: adjusted OR 1.26 (95% CI 1.12 to 1.42) at 18 years for >=1 ASB/day vs none
   Certainty: Drinks with any sweeteners, sucralose not singled out; in Denmark 1996-2002 aspartame/acesulfame predominated.
   Br J Nutr, 2025 · checked 2026-10-07 · we read the abstract
10. ev-sucg-10 · Observational data · population-based birth cohort · n = 3033
    Compared with no consumption, daily consumption of artificially sweetened beverages was associated with a 0.20-unit increase in infant BMI z score (adjusted 95% CI, 0.02-0.38) and a 2-fold higher risk of infant overweight at 1 year of age (adjusted odds ratio, 2.19; 95% CI, 1.23-3.88).
    
    Who: healthy pregnant women, CHILD Study, Canada 2009-2012; infant BMI measured at 1 year
    Effect: adjusted OR 2.19 (95% CI 1.23 to 3.88); BMI z +0.20 (0.02 to 0.38)
    Certainty: Sweeteners not distinguished; observational.
    JAMA Pediatr, 2016 · checked 2026-10-07 · we read the abstract
11. ev-sucg-11 · Laboratory or animal data · animal experiment · n = 14 vs 14 pregnant mice
    It was found that the proportion of pregnant mice bearing offspring with heart defects was much higher in the sucralose group (71.4%, 10 out of 14) than that in the control group (14.3%, 2 out of 14) (Figures 1A and 1B).
    
    Who: pregnant mice, sucralose in drinking water in early pregnancy (about 181.6 mg/kg/day, roughly 14.7 mg/kg/day human-equivalent)
    Effect: dams with affected offspring 71.4% (10/14) vs 14.3% (2/14)
    Certainty: Mice; not transferred to humans; one experiment in 2026, not replicated.
    iScience, 2026, High sucralose exposure in early pregnancy increases the susceptibility of heart defects in mice offspring · checked 2026-10-07 · we read the fulltext
12. ev-sucg-12 · Position of an expert body · regulatory risk assessment (EFSA FAF Panel) · n = —
    Taking into account the available dataset, the Panel concluded that there is no need to change the current ADI of 15 mg/kg bw per day of sucralose (E 955).
    
    Who: EU population, all age groups
    Effect: ADI 15 mg/kg bw per day unchanged
    Certainty: Pregnancy is not singled out separately.
    EFSA Journal 2026, Re-evaluation of sucralose (E 955) as a food additive · checked 2026-10-07 · we read the fulltext
13. ev-sucg-13 · Position of an expert body · regulatory risk assessment (EFSA FAF Panel) · n = —
    In the case of the HOCs with data available only from animal studies (namely ‘haematotoxicity’, ‘reproductive toxicity’, ‘maternal and developmental toxicity’ and ‘neurotoxicity’) the integration of evidence was done considering the option ‘missing data’
    
    Who: EFSA hazard assessment, reproductive and maternal/developmental toxicity
    Effect: human evidence stream for reproductive and developmental toxicity: missing data
    Certainty: Knowledge boundary (axis 9): the body lacks data on pregnant people.
    EFSA Journal 2026, Re-evaluation of sucralose (E 955) as a food additive · checked 2026-10-07 · we read the fulltext
14. ev-sucg-14 · Position of an expert body · agency safety review summary · n = —
    To determine the safety of sucralose, the FDA reviewed more than 110 studies designed to identify possible toxic effects, including studies on the reproductive and nervous systems, carcinogenicity, and metabolism.
    
    Who: general population
    Effect: review of more than 110 studies, including reproductive and nervous system studies
    Certainty: Pregnancy is not mentioned separately; the FDA ADI itself is not confirmed by this quote.
    US FDA, Aspartame and Other Sweeteners in Food · checked 2026-10-07 · we read the section
15. ev-sucg-15 · Position of an expert body · agency position · n = —
    Based on the available scientific evidence, sweeteners authorized by the FDA are safe for the general population under certain conditions of use.
    
    Who: general population
    Effect: safe under conditions of use; no pregnancy-specific statement
    Certainty: "General population": pregnant women are not named separately.
    US FDA, Aspartame and Other Sweeteners in Food · checked 2026-10-07 · we read the section
16. sclr-daily-r8-11 · Position of an expert body · regulatory risk assessment (EFSA FAF Panel) · n = —
    Taking into account the available dataset, the Panel concluded that there is no need to change the current ADI of 15 mg/kg bw per day of sucralose (E 955).
    
    Who: EU population exposure estimates, all age groups
    Effect: ADI 15 mg/kg bw per day unchanged; mean and P95 exposure below ADI
    Certainty: agency opinion; FDA ADI differs (5 mg/kg), not in local layers
    EFSA Journal 2026, Re-evaluation of sucralose (E 955) as a food additive · checked 2026-09-29 · we read the fulltext