butternut-squash
A carotenoid-dense winter squash: one cup delivers well over a day's vitamin A plus generous fiber and potassium.
Moderate evidence
🥦Vegetables
Evidence tier
Moderate
Research weight
Citations
11 verified / 11
Classification
Vegetables
❝
What the evidence says. Several controlled trials; effects real but modest or context-dependent.
Nutrition per serving 1 cup cubed, baked (205 g)
- Sugars 4.1 g2%
- Fibre 6.6 g3%
- Other carbs 10.8 g5%
- Protein 1.8 g1%
- Other 181.7 g89%
82 kcal1.8 g protein6.6 g fiber4.1 g sugar
| Nutrient | Per serving | % daily value |
|---|---|---|
| Vitamin C | 31 mg | 34% |
| Fiber | 6.6 g | 24% |
| Potassium | 582 mg | 12% |
| Folate | 39 µg | 10% |
| Vitamin A | 1144 µg | 127% |
| Vitamin K | 2.1 µg | 2% |
| Vitamin B6 | 0.25 mg | 15% |
| Manganese | 0.35 mg | 15% |
| Copper | 0.12 mg | 13% |
| Vitamin E | 2.6 mg | 17% |
| Magnesium | 59 mg | 14% |
| Calcium | 84 mg | 6% |
Composition data: USDA FoodData Central ↗
What is butternut-squash?
butternut-squash is a vegetable used for high provitamin-a carotenoid density. NutriDex grades the human evidence as Moderate. Butternut squash is exceptionally rich in provitamin-A carotenoids (alpha- and beta-carotene, beta-cryptoxanthin), the bioactives behind the strongest human evidence for this food group. Prospective-cohort meta-analyses tie higher dietary and circulating carotenoids to lower all-cause mortality, type 2 diabetes risk, and breast cancer risk, while its soluble/insoluble fiber aligns with robust dose-response data linking fiber to reduced cardiovascular and total mortality. Critically, these benefits track with carotenoid-rich whole foods, not high-dose beta-carotene supplements, which increased lung cancer risk in smokers.
Purported Benefits
✓High provitamin-A carotenoid density
✓Associated with lower all-cause mortality
✓Linked to reduced type 2 diabetes risk
✓Fiber supports cardiometabolic health
✓Good potassium and vitamin C source
Dosing & Compounds
Typical Dose
Standard serving: 1 cup cubed, baked (205 g). Eat whole (with skin where edible); favour whole fruit over juice.
Active Compounds
Safety & Cautions
Generally very safe and well tolerated. Carotenoid benefits apply to whole foods; high-dose synthetic beta-carotene supplements (20-30 mg/day) raised lung cancer risk in smokers and should be avoided in that group. Very high intake of carotenoid-rich vegetables can cause harmless skin yellowing (carotenodermia). As a fructan/FODMAP-containing vegetable, large portions may trigger gas or bloating in sensitive IBS patients. Educational only — always check with your doctor or pharmacist before combining butternut-squash with any medicine.
Key Studies ★ 11 studies
dose-response meta-analysis
Aune-style carotenoid breast cancer review 2023
✓ Full text
Higher circulating total carotenoids and beta-carotene were associated with lower breast cancer risk (e.g. RR ~0.74 per 50 ug/dL beta-carotene), with consistent inverse signals for alpha-carotene.
dose-response meta-analysis
Hou et al. 2023
✓ PubMed
Higher total dietary fiber was linked to lower all-cause (RR 0.90), cardiovascular (RR 0.87) and cancer (RR 0.91) mortality, with vegetable fiber among protective sources.
Systematic review
Nutrients Systematic Review 2024
✓ Full text
A systematic review of 38 interventional studies (2011-2024) found blood levels of alpha-carotene, beta-cryptoxanthin, lutein/zeaxanthin and lycopene were inversely correlated with CVD events, with carotenoid-rich foods more effective than supplements.
dose-response meta-analysis
Jiang et al. 2021
✓ PubMed
Across 13 prospective cohorts, higher dietary beta-carotene was inversely associated with type 2 diabetes (highest vs lowest pooled RR ~0.78), with significant inverse trends for alpha-carotene and total carotenoids.
meta-analysis
Huang et al. 2016
✓ Full text
Pooled prospective studies: highest vs lowest circulating beta-carotene cut all-cause mortality risk (RR 0.69, 95% CI 0.59-0.80); higher dietary intake also protective (RR 0.83, 95% CI 0.78-0.88).
systematic review & meta-analysis
Reynolds et al. 2019 (Lancet)
✓ Source
Higher dietary fiber intake (25-29 g/day optimal) was associated with reduced all-cause and cardiovascular mortality and lower incidence of diabetes, with a 15-30% risk reduction across outcomes.
RCT
Mabela 2024
✓ Full text
In a 6-month cluster-randomized trial of 276 South African preschoolers, twice-weekly Cucurbita moschata (butternut) seed paste vs squash flesh significantly improved serum zinc and iron status compared with the flesh control group.
Safety / toxicology
Mihai 2024
✓ Full text
In vitro digestion of organic Cucurbita moschata showed industrial freezing did not significantly change alpha- and beta-carotene bioaccessibility, while frozen squash retained higher bioaccessible epicatechin (117.5 mg/kg) and syringic acid (32.0 mg/kg) than fresh fruit.
RCT (safety)
ATBC Study (Middha et al. 2019)
✓ PubMed
In the Alpha-Tocopherol Beta-Carotene trial, high-dose synthetic beta-carotene (20 mg/day) increased lung cancer incidence in heavy smokers, underscoring that benefit is from food carotenoids, not supplements.
RCT
AREDS2 Research Group 2013
✓ PubMed
In this randomized trial, substituting lutein/zeaxanthin for beta-carotene lowered progression to late age-related macular degeneration (HR 0.82, 95% CI 0.69-0.96 vs beta-carotene).
Observational
Nutrition Research 2025 (NHANES)
✓ PubMed
In 1285 NHANES adults with advanced cardiovascular-kidney-metabolic syndrome, higher combined serum carotenoid concentrations were significantly associated with lower all-cause mortality, with lycopene contributing the largest individual weight.