Macaroni and pasta: a low glycemic starch never tested alone

Pasta has one finding from pooled trials, and it comes with a catch. A meta-analysis of 32 trial comparisons in 2,448 adults found that pasta eaten within low glycemic index diets lowered body weight by 1.4 lb (95% CI 0.93 to 1.9; metric: 0.63 kg, 0.42 to 0.84) against higher glycemic index diets. The same review found no trial that tested pasta on its own. A review of over 4,000 glycemic index tests found pasta usually scores 55 or below, with values consistent around the world. In a randomized crossover trial in 30 Chinese and Indian adults, semolina and wholegrain spaghetti scored 53 and 54, against 80 for white rice.

How much is actually in it

• Dry enriched spaghetti in USDA Foundation Foods averaged 230 micrograms folate and 3.9 mg iron per 3.5 oz (100 g) across 7 samples, while whole grain spaghetti had about twice the zinc. — 7 samples of dry enriched spaghetti and 3 of dry whole grain spaghetti, USDA Foundation Foods (n = 7) Evidence E source
  Enriched: folate 229.6 ug/100 g (range 172 to 318), iron 3.89 mg (3.19 to 4.91), zinc 1.49 mg (1.25 to 1.72); whole grain: zinc 2.95 mg (2.46 to 3.36), iron 4.52 mg (2.34 to 6.86)

What a real portion looks like

• In the US survey food database one cup of cooked pasta weighs 4.9 oz (140 g), one ounce of dry pasta yields 80 g cooked, and one cup of macaroni and cheese weighs 8.1 oz (230 g). — US food survey portion weights Evidence E source
  Pasta cooked 1 cup 140 g; 1 oz dry yields 80 g; macaroni or noodles with cheese 1 cup 230 g

What your body absorbs

• In 15 healthy volunteers, pasta made with 35% faba bean flour kept the low glycemic and insulin index of plain durum wheat pasta. — 15 healthy volunteers, three test meals (n = 15) Evidence B source
  Glycemic and insulin index unchanged with 35% faba bean; very high temperature drying reduced digestive discomfort

What cooking and storage change

• USDA retention tables estimate that boiling and draining pasta keeps 30% of potassium, 65% of thiamin, 70% of folate and 75% of iron. — food group Cereal Grains and Pasta, pasta boiled and drained Evidence E source
  Retained: potassium 30%, sodium 50%, thiamin 65%, niacin 65%, folate 70%, iron 75%, zinc 100%
• In a randomized study of 12 healthy adults, cooking pasta for 11, 16.5 or 22 minutes made no significant difference to blood glucose or insulin responses. — 12 healthy subjects, three test meals of 50 g starch on consecutive days (n = 12) Evidence B source
  No significant difference between cooking times in plasma indices or breath hydrogen

What it does to your health

• A meta-analysis of 32 trial comparisons in 2448 adults found that pasta eaten within low glycemic index diets lowered body weight by 1.4 lb (0.63 kg) compared with higher glycemic index diets. — 2448 adults in randomized trials of 3 weeks or longer (n = 2448) Evidence A source
  Body weight MD -1.4 lb (95% CI -1.9 to -0.93; metric: -0.63 kg, -0.84 to -0.42), BMI MD -0.26 kg/m2 (95% CI -0.36 to -0.16)
• A 2021 systematic review of over 4000 glycemic index values found pasta was usually a low glycemic index food, at 55 or below on the glucose scale. — published and unpublished glycemic index tests worldwide (n = over 4000 items) Evidence C source
  Pasta usually GI 55 or below, with consistent values around the world
• Cohort data pooled from 17 studies with more than 875,000 people did not link refined grain intake, including pasta, with cardiovascular disease (HR 1.08). — over 875,000 participants in 17 prospective cohort studies (n = 875000) Evidence C source
  CVD HR 1.08 (95% CI 0.99 to 1.18), stroke HR 1.06 (0.92 to 1.23), heart failure HR 0.95 (0.77 to 1.16)
• In a randomized crossover trial in 20 adults, pasta with 30% red sorghum flour cut energy eaten at the next lunch by 794 kJ compared with durum wheat pasta. — 20 healthy individuals, breakfast test meals with 50 g available carbohydrate (n = 20) Evidence B source
  Ad libitum lunch energy -794.17 kJ (95% CI -1274.77 to -313.57); glucose iAUC -651 mg/dL (-36.11 mmol/l) x min

Safety, limits and interactions

• Laboratory data pooled from 28 studies of wheat foods, mostly bread, cookies and pasta, found acrylamide the most concentrated processing contaminant at 136.29 micrograms per kg. — wheat-based food samples in 28 studies (n = 28 studies) Evidence D source
  Acrylamide 136.29 ug/kg, HMF 70.59 ug/kg, PAHs 0.11 ug/kg
• A case series of 3 family members describes Bacillus cereus emetic food poisoning, a toxin type often linked to pasta and rice, in which a 1-year-old died. — three family members after eating reheated fried rice (n = 3) Evidence C source
  Vomiting within 30 minutes, one child death from acute encephalopathy
• FDA links vomiting-type B. cereus outbreaks mainly to rice products, with pasta also implicated. Its emetic toxin stays stable after heating at 121 C for 30 minutes, so cooking might not disable it. FDA advises keeping food refrigerated at 40 F or lower. — General population (home food handling) (n = -) Evidence E source
  Refrigerate at 40 F or lower, emetic toxin stable after 121 C for 30 minutes

What people believe that the data does not support

• The EU refused to authorize the claim that carbohydrates in pasta products give a low and slow blood sugar response. — foods marketed in the EU Evidence E source
  Claim non-authorized, no effect size
• In a randomized trial in 14 healthy men, slowly processed pasta gave the same blood glucose and insulin response as normally processed pasta after 3.5 oz (100 g) meals. — 14 healthy male volunteers, aged 31 on average (n = 14) Evidence B source
  No difference in glucose tolerance, insulin or incretin response between pasta types

Who this works differently for

• In a randomized crossover trial in 30 Chinese and Indian adults, semolina and wholegrain spaghetti had glycemic index values of 53 and 54 against 80 for white rice. — 30 Chinese and Indian adults, BMI 18.5 to 25 (n = 30) Evidence B source
  GI 53 semolina spaghetti, 54 wholegrain spaghetti, 74 mee pok noodles, 80 white rice (p < 0.005)
• In observational data from about 6000 older Mediterranean adults with overweight, each extra daily serving of pasta was associated with 4.9 lb (2.23 kg) more weight loss over 2 years, which does not show that pasta caused it. — about 6000 older adults with overweight or obesity at high cardiometabolic risk, PREDIMED-Plus (n = 6000) Evidence C source
  Per additional serving: body weight -4.9 lb (-7.7 to -2.2; metric: -2.23 kg, -3.47 to -0.98), BMI -0.86, waist -0.76 in (-1.92 cm) over 2 years

What is still unknown

• The same meta-analysis found no trial at all testing pasta on its own for body weight, only 32 comparisons of pasta inside low glycemic index diets. — randomized trials in adults searched through 7 February 2017 (n = 0 trials of pasta alone) Evidence A source
  0 trial comparisons of pasta alone, 32 in low-GI patterns
• A systematic review of cohorts and trials found pasta meals give lower blood glucose than bread or potato but found no evidence on how pasta intake affects cardiometabolic disease. — prospective cohort studies and randomized dietary trials on pasta Evidence C source
  Lower postprandial glucose vs bread or potato; no long-term disease evidence

The bottom line

Dry enriched spaghetti averaged 230 micrograms of folate and 3.9 mg of iron per 3.5 oz (100 g) across 7 USDA samples, and both are added by fortification. Whole grain spaghetti had 2.95 mg of zinc against 1.49 mg, about twice as much, from only 3 samples. One ounce of dry pasta cooks up to 80 g, a cup of cooked pasta weighs 4.9 oz (140 g), and a cup of macaroni and cheese weighs 8.1 oz (230 g). A USDA group factor from 1975 estimates that boiling and draining pasta keeps 30% of potassium, 70% of folate, 75% of iron and all of the zinc. In one small 1990 trial in 12 healthy adults, pasta cooked for 11, 16.5 or 22 minutes gave no significant difference in blood glucose or insulin measures. In 14 healthy men, slowly processed pasta gave the same glucose and insulin response as normally processed pasta after a single meal. The EU refused to authorize the claim that carbohydrates in pasta give a low and slow blood sugar response, which means the evidence was judged insufficient for that wording. Long-term data are thin and indirect. A review of cohorts and trials found that pasta meals give lower blood glucose after eating than bread or potato meals, and no evidence on how pasta intake affects heart or metabolic disease. Pooled cohorts of over 875,000 people did not link refined grains, pasta included, with cardiovascular disease (HR 1.08, 95% CI 0.99 to 1.18). In about 6,000 older Mediterranean adults with overweight, each extra daily serving of pasta was linked with 4.9 lb (2.23 kg) more weight loss over 2 years, in observational data where average intake was only 8 to 9 g of dry pasta a day. That is an association inside a trial cohort, and it does not show that eating more pasta causes weight loss. Modified pastas are different products. In 20 adults, pasta made with 30% red sorghum flour cut energy eaten at the next lunch by 794 kJ (95% CI 314 to 1,275) against durum wheat pasta. In 15 volunteers, pasta made with 35% faba bean flour kept the low glycemic and insulin index of plain pasta. The safety cards are indirect. Laboratory data from 28 studies of wheat foods, mostly bread, cookies and pasta without separating them, found acrylamide the most concentrated processing contaminant at 136.29 micrograms per kg. A case series of three family members with Bacillus cereus poisoning involved reheated fried rice, the child who died was 1 year old, and the authors note that this toxin type, which forms in the food before it is eaten, is often linked to pasta and rice. We have no card yet on how cooked pasta or rice should be cooled, stored or reheated, or on which age groups are most at risk, so this page cannot give you that step, and reheating should not be read as making leftover pasta safe. We found no card on celiac disease, wheat allergy, pregnancy or drug interactions for pasta.

Sources

1. mpa-r1-01 · reference dataset
   Pasta, dry, enriched, spaghetti | Folate, total 229.6 UG range 172.0-318.0, samples 7 | Iron, Fe 3.887 MG range 3.19-4.91, samples 7 | Zinc, Zn 1.493 MG range 1.25-1.72, samples 7 || Pasta, dry, whole grain, spaghetti | Zinc, Zn 2.95 MG range 2.46-3.36, samples 3 | Iron, Fe 4.523 MG range 2.34-6.86, samples 3
   USDA FoodData Central, Foundation Foods, release 2026-04-30 · checked 2026-09-28
2. mpa-r1-02 · reference dataset
   Pasta, cooked (FNDDS 56130000) | 1 cup, cooked 140 g | 1 oz, dry, yields 80 g || Macaroni or noodles with cheese (FNDDS 58145110) | 1 cup 230 g
   USDA FNDDS 2021-2023 · checked 2026-09-28
3. mpa-r1-13 · randomized crossover trial
   When enriched with 35% legume flour, pasta maintained its nutritionally valuable low glycemic and insulin index, despite its weaker protein network.
   Food Funct, 2015 · checked 2026-09-28
4. mpa-r1-03 · reference dataset
   USDA-RETN-R6:381 PASTA,BOILED,DRAINED | potassium_mg 30% | thiamin_mg 65% | folate_total_ug 70% | iron_mg 75% | zinc_mg 100%
   USDA Table of Nutrient Retention Factors, Release 6 (2007) · checked 2026-09-28
5. mpa-r1-04 · randomized crossover trial
   During 3 consecutive days, one of three pasta test meals (50 g starch) cooked for 11, 16.5, and 22 min was served to each volunteer in a random order. ... No significant differences were found between cooking times and plasma indices, orocecal transit time, or incremental hydrogen excretion (delta peak hydrogen).
   Am J Clin Nutr, 1990 · checked 2026-09-28
6. mpa-r1-05 · meta-analysis of RCTs
   Pasta in the context of low-GI dietary patterns significantly reduced body weight (MD=-0.63 kg; 95% CI -0.84 to -0.42 kg) and BMI (MD=-0.26 kg/m2; 95% CI -0.36 to -0.16 kg/m2) compared with higher-GI dietary patterns.
   BMJ Open, 2018 · checked 2026-09-28
7. mpa-r1-08 · systematic review
   Dairy products, legumes, pasta, and fruits were usually low-GI foods (≤55 on the 100-point glucose scale) and had consistent values around the world.
   Am J Clin Nutr, 2021 · checked 2026-09-28
8. mpa-r1-09 · meta-analysis of cohort studies
   Meta-analyses of hazard ratios (HR) and 95% confidence intervals (CI) obtained from 17 prospective cohort studies (>875,000 participants) indicated that refined grain intake was not associated with risk of CVD (HR = 1.08, 95% CI, 0.99-1.18, I2 = 70%; 9 cohorts)
   Trends Cardiovasc Med, 2024 · checked 2026-09-28
9. mpa-r1-14 · randomized crossover trial
   Energy intake at ad libitum lunch was significantly lower after the RSP meal than after the CP meal (-794.17 ± 163.25 kJ; 95% CI: -1274.77 ~ -313.57; P = 0.001).
   Eur J Clin Nutr, 2025 · checked 2026-09-28
10. mpa-r1-15 · meta-analysis of laboratory studies
    Most studies (69.7%) evaluated acrylamide in bread, cookies, and pasta, while PAHs (26.2%) were determined mainly in wheat grains and pasta. HMF was the least determined contaminant (4.1%), with only four studies on cookies included in the meta-analysis. The highest concentration was for acrylamide (136.29 µg·kg-1)
    Crit Rev Food Sci Nutr, 2023 · checked 2026-09-28
11. mpa-r1-16 · case series
    The emetic type, which is often linked to pasta and rice, arises from a preformed toxin, cereulide, in food.
    Pediatrics, 2010 · checked 2026-09-28
12. sf-bc-r3-7 · agency advice
    The vomiting-type outbreaks generally have been associated with rice products; however, other starchy foods, such as potato, pasta, and cheese products, also have been implicated. Food mixtures, such as sauces, puddings, soups, casseroles, pastries, and salads, frequently have been linked with food-poisoning outbreaks. ... One of the most important things you can do to protect yourself from infection with B. cereus is to keep your food refrigerated at 40°F or lower. ... Cooking may kill the bacteria, but it might not disable the toxin that causes the vomiting type of illness. ... The non-antigenic peptide is stable after heating at 121°C for 30 minutes, cooling at 4°C for 60 days, and at a pH range of 2 to 11.
    US FDA, Bad Bug Book 2nd ed. (2012), Bacillus cereus and other Bacillus species · checked 2026-10-08
13. mpa-r1-11 · regulatory register
    POL-HC-6873 Carbohydrates in pasta products Kolhydrater i pasta ger ett lågt och långsamt blodsockersvar/har ett lågt glykemiskt index (GI). Carbohydrates in pasta products provide a low and slow blood sugar response/have a low glycaemic index (GI). Non-authorised
    EU Register on nutrition and health claims, claim POL-HC-6873, snapshot 2026-09-21 · checked 2026-09-28
14. mpa-r1-12 · randomized crossover trial
    Despite the common belief of a different impact of normally processed and slowly processed pasta on glucose metabolism, they show a superimposable post-prandial metabolic response after a single meal in male healthy individuals.
    Nutrients, 2021 · checked 2026-09-28
15. mpa-r1-07 · randomized crossover trial
    The current evaluation showed that semolina spaghetti and wholegrain spaghetti can be classified as low GI products, with a GI of 53 and 54, respectively, significantly lower than wheat based mee pok noodles (74) and rice (80) (p < 0.005).
    Nutrients, 2021 · checked 2026-09-28
16. mpa-r1-10 · longitudinal cohort analysis
    When fully adjusted, every additional serving of pasta was associated with significantly greater 2 y decreases in body weight (-2.23(-3.47, -0.98 kg), BMI (-0.86(-1.27, -0.34 kg/m2) and WC (-1.92 (-3.46, -0.38 cm).
    J Am Nutr Assoc, 2025 · checked 2026-09-28
17. mpa-r1-06 · meta-analysis of RCTs
    We identified no trial comparisons of the effect of pasta alone and 32 trial comparisons (n=2448 participants) of the effect of pasta in the context of low-GI dietary patterns.
    BMJ Open, 2018 · checked 2026-09-28
18. mpa-r1-17 · systematic review
    Pasta meals have significantly lower postprandial glucose response than bread or potato meals, but evidence was lacking in terms of how the intake of pasta can influence cardio-metabolic disease risk.
    Nutr Metab Cardiovasc Dis, 2017 · checked 2026-09-28