swiss-chard
A nitrate- and vitamin K-dense leafy green from the beet family.
Moderate evidence
🥦Vegetables
Evidence tier
Moderate
Research weight
Citations
8 verified / 8
Classification
Vegetables
❝
What the evidence says. Several controlled trials; effects real but modest or context-dependent.
Nutrition per serving 1 cup chopped, raw (36 g)
- Sugars 0.4 g1%
- Fibre 0.6 g2%
- Other carbs 0.3 g1%
- Protein 0.6 g2%
- Other 34.1 g95%
7 kcal0.6 g protein0.6 g fiber0.4 g sugar
| Nutrient | Per serving | % daily value |
|---|---|---|
| Vitamin C | 11 mg | 12% |
| Fiber | 0.6 g | 2% |
| Potassium | 136 mg | 3% |
| Folate | 5 µg | 1% |
| Vitamin A | 110 µg | 12% |
| Vitamin K | 299 µg | 249% |
| Vitamin B6 | 0.04 mg | 2% |
| Manganese | 0.13 mg | 6% |
| Copper | 0.06 mg | 7% |
| Vitamin E | 0.68 mg | 5% |
| Magnesium | 29 mg | 7% |
| Calcium | 18 mg | 1% |
Composition data: USDA FoodData Central ↗
What is swiss-chard?
swiss-chard is a vegetable used for supports cardiovascular health (leafy-green association). NutriDex grades the human evidence as Moderate. Swiss chard is a Beta vulgaris leafy green exceptionally rich in vitamin K, provitamin-A carotenoids, magnesium, and dietary nitrate. The strongest human evidence is indirect and category-level: large prospective cohorts and meta-analyses consistently link green leafy vegetable intake to lower cardiovascular disease, slower cognitive decline, and reduced glaucoma risk, while pooled RCTs of inorganic/dietary nitrate show modest blood-pressure and vascular benefits in healthy adults. Chard-specific clinical trials are sparse, so benefits are inferred from its leafy-green and nitrate profile.
Purported Benefits
✓Supports cardiovascular health (leafy-green association)
✓Provides dietary nitrate that may modestly lower blood pressure
✓Linked to slower age-related cognitive decline
✓Associated with lower glaucoma risk
✓Outstanding source of vitamin K and provitamin-A carotenoids
Dosing & Compounds
Typical Dose
Standard serving: 1 cup chopped, raw (36 g). Eat whole (with skin where edible); favour whole fruit over juice.
Active Compounds
Safety & Cautions
Very high in vitamin K (~300 ug per cup raw), which can interfere with warfarin/vitamin-K-antagonist anticoagulants — keep intake consistent and consult a clinician. Also high in oxalates, so people prone to calcium-oxalate kidney stones should moderate intake; oxalate also reduces absorption of the calcium it contains. Educational only — always check with your doctor or pharmacist before combining swiss-chard with any medicine.
Key Studies
meta-analysis
Shannon 2025
✓ Full text
GRADE-assessed dose-response meta-analysis of RCTs found dietary/plasma nitrate significantly improved blood pressure and vascular function (flow-mediated dilation) biomarkers.
meta-analysis
Zurbau 2020
✓ Source
Systematic review/meta-analysis (95 cohorts) found one daily serving of green leafy vegetables associated with 12-18% lower risk of CVD, CHD, and stroke.
meta-analysis
Jackson 2018
✓ PubMed
Meta-analysis of 19 RCTs found inorganic nitrate lowered systolic blood pressure by 2.42 mmHg (95% CI -4.28 to -0.57, p=0.01) in healthy adults, with no significant effect in hypertensives.
meta-analysis
Pollock 2016
✓ Full text
Meta-analysis of 8 cohorts found green leafy/cruciferous vegetable intake associated with ~16% lower cardiovascular disease incidence (RR 0.842, 95% CI 0.753-0.941, p=0.002).
meta-analysis
Aune 2017
✓ PubMed
Dose-response meta-analysis of 95 studies showed CVD and all-cause mortality risk fell with fruit/vegetable intake up to ~800 g/day, with green leafy vegetables among the most protective sources.
RCT
Blekkenhorst 2018
✓ Full text
Randomized crossover/controlled trials of nitrate-rich leafy vegetables support nitrate-to-nitric-oxide conversion as a plausible mechanism for vascular benefit (AJCN RCT, n=243).
prospective cohort
Morris 2018
✓ Full text
Prospective study (n=960, ~4.7 y) found ~1 serving/day of green leafy vegetables associated with slower cognitive decline equivalent to being 11 years younger.
prospective cohort
Kang 2016
✓ PubMed
In two cohorts (n=104,987; 1,483 POAG cases), highest vs lowest dietary nitrate/green-leafy-vegetable intake was associated with ~20-30% lower primary open-angle glaucoma risk.