Churros: no composition record, and one study that names them

A single deep-fried snack of sugar and fat left brain blood-flow reactivity unchanged overall in 24 fasted healthy adults, with a mean difference in Breath Holding Index of -0.11 (p = 0.40) after a deep-fried Mars bar against porridge. The result that reached significance fell on the men: the authors report impaired cerebrovascular reactivity in males, the gap between the sexes being 0.65 (95% CI 0.30 to 1.00, p = 0.0003). That came from a secondary analysis of a surrogate measurement in a group of 24 young people. This is the closest thing to a trial about a churro that we found. There is no composition record for churros anywhere we looked, not in the USDA tables and not in the UK one, so this page cannot tell you the sugar, fat or energy in one. The portion tables know the weights and nothing else. The only study that names churros surveyed 122 elderly residents of Madrid in 1996, where people of normal weight said they preferred churros at breakfast less often than overweight and obese people did, and ate more varied breakfasts. A preference ticked on a questionnaire cannot show which came first, and the authors put it no more strongly than that.

What a real portion looks like

• One regular churro counts as 45 g in the USDA portion tables and a miniature one as 15 g, and when a survey respondent gives no size the same tables assume 45 g. — USDA FNDDS portion records for Churros, FNDDS code 53520200, FDC id 2708070, WWEIA category Doughnuts, sweet rolls, pastries (n = 3 household measures) Evidence E source
  1 regular 45 g, 1 miniature 15 g, quantity not specified 45 g

What cooking and storage change

• Acrylamide already formed in a food mostly breaks down during storage, fastest in dry products kept at 25 degrees or above, while freezing holds it in place. — Systematic review of storage studies on acrylamide levels in processed foods (n = not stated in the abstract) Evidence D source
  Acrylamide concentrations decreased in most matrices, largest reductions in low-moisture products at temperatures at or above 25 degrees C, freezing largely preserved content
• In 12 obese insulin-resistant women the C-peptide response differed between two meals that differed only in whether the extra-virgin olive oil was fried or served raw (P = 0.0020 at 120 minutes), while the five lean subjects showed no difference. — 12 obese insulin-resistant women with body mass index 32.8 and five lean subjects, two meals in random order after an overnight fast (n = 17 (12 obese, 5 lean)) Evidence B source
  C-peptide AUC differed between the two meals at 120 min (P=0.0020), 150 min (P=0.0039) and 180 min (P=0.0039), no difference in lean subjects

What it does to your health

• Eight studies with 2843 cases and 309 920 comparison participants found no association between dietary acrylamide and kidney cancer, with a relative risk of 1.12 (95% CI 0.97 to 1.28) for the highest against the lowest intake. — Eight epidemiological studies, 2843 renal cell carcinoma cases and 309 920 controls or participants (n = 2843 cases, 309 920 participants) Evidence C source
  RR 1.12 (95% CI 0.97 to 1.28) highest versus lowest acrylamide intake, and 1.11 (0.93 to 1.32) among never smokers

Safety, limits and interactions

• Across 28 pooled measurement studies of wheat-based foods, acrylamide was the contaminant found at the highest level, 136.29 µg per kg, ahead of hydroxymethylfurfural at 70.59 and polycyclic aromatic hydrocarbons at 0.11. — 28 studies of processing contaminants in wheat-based foods out of 1479 records screened (n = 28 studies) Evidence D source
  Acrylamide 136.29 µg/kg, HMF 70.59 µg/kg, PAHs 0.11 µg/kg as pooled highest concentrations
• Women with the highest pregnancy exposure to acrylamide had 20% higher odds of a small-for-gestational-age baby (OR 1.20, 95% CI 1.08 to 1.33) and babies 131 g lighter, pooled across 53 870 mother and newborn pairs. — Five eligible studies including 53 870 mother-newborn pairs, mean estimated dietary acrylamide exposure 21.9 µg per day (n = 53 870 pairs) Evidence C source
  Highest quartile of acrylamide haemoglobin adducts: SGA OR 1.20 (95% CI 1.08 to 1.33), birth weight -131 g (-204 to -58), head circumference -0.31 cm (-0.58 to -0.04)

Who this works differently for

• A single deep-fried sugar and fat snack did not change brain blood-flow reactivity overall in 24 young adults (mean difference -0.11, p = 0.40). The authors report a significant impairment in the men, the gap between the sexes being 0.65 (95% CI 0.30 to 1.00). — 24 fasted healthy adults, mean age 21.5 years, 14 men, randomised to a deep-fried Mars bar then porridge or the reverse (n = 24) Evidence B source
  Breath Holding Index mean difference after the deep-fried bar versus porridge -0.11 (p=0.40) overall, significant impairment of cerebrovascular reactivity in males, mean difference women minus men 0.65 (95% CI 0.30 to 1.00, p=0.0003)
• The only study in the corpus that names churros looked at 122 elderly residents of Madrid, where normal-weight people preferred churros for breakfast less often than overweight and obese people did. — 122 elderly Spanish people, 65 men and 57 women, aged 75.7 years on average, 58% overweight or obese (n = 122) Evidence C source
  Normal-weight subjects showed less preference for churros at breakfast than overweight and obese subjects, and ate more varied breakfasts

What is still unknown

• Fourteen prospective cohorts found no link between dietary acrylamide and breast cancer (RR 0.95, 95% CI 0.90 to 1.01), endometrial cancer (RR 1.03, 0.89 to 1.19) or ovarian cancer (RR 1.02, 0.84 to 1.24). — Fourteen prospective cohort studies of dietary acrylamide intake and women's cancers, searched to August 2020 (n = 14 cohorts) Evidence C source
  Breast RR 0.95 (95% CI 0.90 to 1.01), endometrial RR 1.03 (0.89 to 1.19), ovarian RR 1.02 (0.84 to 1.24), null in every subgroup tested
• The 28 studies on acrylamide and heart disease point in opposite directions at once, since higher exposure went with higher cardiovascular mortality yet with lower glucose, lower lipids and less diabetes and obesity. — 28 studies on acrylamide exposure and cardiovascular risk, predominantly from the US NHANES sample and cross-sectional in design (n = 28 studies) Evidence C source
  Higher acrylamide exposure associated with increased cardiovascular mortality but inversely with glucose, lipids, diabetes, obesity and metabolic syndrome, while its metabolite glycidamide was positively associated with all of them

The bottom line

Frying wheat dough makes acrylamide, and that is where the research actually sits. Across 28 pooled measurement studies of wheat-based foods, acrylamide was the contaminant present at the highest level, 136.29 µg per kg, ahead of hydroxymethylfurfural at 70.59 and polycyclic aromatic hydrocarbons at 0.11. Those studies measured bread, biscuits and pasta. Churros were not among them, so the number describes a class of wheat foods rather than dough from a fryer. Storage hardly applies to something eaten hot, and where it was studied the acrylamide already formed mostly broke down over time, fastest in low-moisture products held at 25 degrees or above, while freezing held it in place. The matrices there were coffee, cocoa, nuts and cereals. What that acrylamide does to healthy adults is mostly a row of null results. Fourteen prospective cohorts found no link with breast cancer (RR 0.95, 95% CI 0.90 to 1.01), endometrial cancer (RR 1.03, 0.89 to 1.19) or ovarian cancer (RR 1.02, 0.84 to 1.24). Eight studies with 2843 kidney cancer cases and 309 920 comparison participants found none for renal cell carcinoma either (RR 1.12, 95% CI 0.97 to 1.28), and the same held among people who had never smoked (RR 1.11, 0.93 to 1.32). An interval that crosses 1 means no signal was found, and dietary questionnaires estimate acrylamide poorly, which is an accepted limit of this whole class of work. The heart is messier. Across 28 studies, mostly cross-sectional and mostly from one United States survey, higher acrylamide exposure went with higher cardiovascular mortality. The same exposure went with lower glucose, lower lipids and less diabetes, obesity and metabolic syndrome, while its metabolite glycidamide went with more of all of them. One review contradicting itself is the honest state of that question, and its authors say so. Who should be careful. Pregnancy is the one place this evidence points in a single direction. Pooled across five studies and 53 870 mother and newborn pairs, women in the highest quartile of acrylamide haemoglobin adducts had 20 percent higher odds of a small-for-gestational-age baby (OR 1.20, 95% CI 1.08 to 1.33). Their babies were 131 g lighter (95% CI -204 to -58), with head circumference 0.31 cm smaller (-0.58 to -0.04). Those are odds and not risk, from observational studies, and the exposure was measured in blood as the sum of all acrylamide in a diet averaging 21.9 µg a day. Nobody weighed anyone's churros. That is the whole of the caution we can source: our cards say nothing about children, allergy or medicines and churros, and absence of a card is not a clean bill. Two more things worth knowing. One regular churro counts as 45 g in the USDA portion tables and a miniature one as 15 g, and when a survey respondent does not say which, those tables assume 45 g. One trial here speaks to the oil and not to the dough. In 12 obese insulin-resistant women with a mean body mass index of 32.8, the C-peptide response differed between two meals of the same food that differed only in whether the extra-virgin olive oil had been fried or served raw (P = 0.0020 at 120 minutes). The abstract we can cite calls them meal A and meal B without saying which one was fried, so this page does not hand you a direction. The five lean subjects showed no such difference. That trial fried courgettes and pasta, and how much oil a churro takes up was no part of it.

Sources

1. chur-daily-r3-10 · food portion dataset
   Churros (FNDDS 53520200, FDC 2708070, WWEIA Doughnuts, sweet rolls, pastries) | 1 regular 45 g | 1 miniature 15 g | Quantity not specified 45 g
   USDA FNDDS, Food and Nutrient Database for Dietary Studies · checked 2026-09-24
2. chur-daily-r3-02 · systematic review of food chemistry experiments
   Overall, AA concentrations decreased in most matrices, with the largest reductions occurring in low-moisture products (coffee, cocoa, nuts), particularly at temperatures ≥25 °C...Storage time and temperature were the primary determinants of AA stability, while freezing largely preserved AA content.
   Food Addit Contam Part A Chem Anal Control Expo Risk Assess, 2026 · checked 2026-09-24
3. chur-daily-r3-07 · randomised controlled crossover trial
   In obese women the AUCs for C-peptide were significantly higher after meal A than after meal B at 120 minutes (W [Wilcoxon sign rank test] = 27.5, P = .0020), 150 minutes (W = 26.5, P = .0039), and 180 minutes (W = 26.5, P = .0039). No differences were found in lean subjects.
   J Med Food, 2011 · checked 2026-09-24
4. chur-daily-r3-05 · meta-analysis of observational studies
   This meta-analysis study included eight studies, 2843 cases, and 309 920 controls/participants...No meaningful association was found for renal cell carcinoma; RR was 1.12 (95% confidence interval (CI): 0.97-1.28).
   J Sci Food Agric, 2020 · checked 2026-09-24
5. chur-daily-r3-01 · meta-analysis of food composition measurements
   The highest concentration was for acrylamide (136.29 µg·kg-1) followed by HMF (70.59 µg·kg-1) and PAHs (0.11 µg·kg-1).
   Crit Rev Food Sci Nutr, 2023 · checked 2026-09-24
6. chur-daily-r3-03 · dose-response meta-analysis of observational studies
   Out of 169 records identified, five original studies were eligible, including 53,870 mother-newborn pairs in total...Higher risk of SGA and lower birth weight and head circumference were observed in the highest quartile of AA-Hb [odds ratio (OR): 1.20 (95% CI: 1.08; 1.33); mean difference (MD): -131 g (95% CI: -204; -58) and -0.31 cm (95% CI: -0.58; -0.04), respectively]
   Environ Res, 2022 · checked 2026-09-24
7. chur-daily-r3-08 · randomised controlled crossover trial
   Deep-fried Mars bar ingestion caused a non-significant reduction in cerebrovascular reactivity relative to control (mean difference in absolute Breath Holding Index after deep-fried Mars bar versus porridge -0.11, p = 0.40). Comparison of the difference between the absolute change in Breath Holding Index between genders demonstrated a significant impairment of cerebrovascular reactivity in males (mean difference women minus men of 0.65, 95% CI 0.30 to 1.00, p = 0.0003).
   Scott Med J, 2014 · checked 2026-09-24
8. chur-daily-r3-09 · cross-sectional dietary survey
   NW subjects more frequently indicated a preference for fruit (Y), juices (Y) and bread (Y and Z) as breakfast foods, and showed less preference for churros (Y) (a traditional Spanish breakfast fritter) than did O subjects.
   J Am Coll Nutr, 1996 · checked 2026-09-24
9. chur-daily-r3-04 · meta-analysis of prospective cohort studies
   We found no significant association between dietary acrylamide intake and the risk of breast (relative risk (RR) 0·95; 95 % CI 0·90, 1·01), endometrial (RR 1·03; 95 % CI 0·89, 1·19) and ovarian cancers (RR 1·02; 95 % CI 0·84, 1·24).
   Br J Nutr, 2021 · checked 2026-09-24
10. chur-daily-r3-06 · systematic review of observational studies
    Higher acrylamide exposure was associated with an increased risk of cardiovascular mortality but was inversely associated with glucose and lipid levels, as well as key cardiovascular risk factors such as diabetes, obesity, and metabolic syndrome...Further research is necessary to fully elucidate the impact of acrylamide on cardiovascular health.
    Nutrients, 2024 · checked 2026-09-24