Black bean salad: the beans lower LDL, a cup brings a third of a day’s sodium

By a meta-analysis of 38 randomized trials in 2095 people, whole pulses eaten at a median 130 g a day for 6 weeks lowered LDL cholesterol by 5.4 mg/dL (95% CI 3.1 to 7.3; metric: 0.14 mmol/L, 0.08 to 0.19). For beans the drop grew by 0.25 mmol/L per half cup, up to 1 cup a day. Those trials tested whole pulses, and we found no study of black bean salad itself. The salad in the US survey recipe is a modest food, giving 94 calories, 3.1 g protein and 3.4 g fiber per 3.5 oz (100 g). A cup of it, 231 g, carries about 809 mg sodium, roughly a third of the 2300 mg Daily Value. That is one standard recipe with no range around it, and salads made at home vary widely.

As people eat it, per 3.5 oz (100 g)

How much is actually in it

• Per 100 g, the US survey recipe for black bean salad gives 94 calories, 3.1 g protein, 3.4 g fiber, 350 mg sodium and 0.9 mg iron. — USDA FNDDS food code 41203030 Black bean salad (WWEIA: bean, pea, legume dishes), per 3.5 oz (100 g) Evidence E source
  Energy 94 calories, protein 3.08 g, fat 3.85 g, fiber 3.4 g, sodium 350 mg, potassium 211 mg, iron 0.9 mg, vitamin C 4.4 mg, folate 35 ug
• A New Zealand supermarket survey found dried legumes the cheapest plant protein at NZ$0.30 per 3.5 oz (100 g), with fiber claims the most common on canned and dried legumes. — Packaged plant protein foods in New Zealand supermarkets: 64 plain and 25 flavored canned legumes, 21 dried legumes, meat analogs Evidence C source
  Dried legumes NZ$0.30 per 3.5 oz (100 g) vs NZ$2.57 for other meat-free products

What a real portion looks like

• One cup of black bean salad (231 g) supplies about 217 calories, 8 g fiber and 809 mg sodium, roughly a third of the 2300 mg Daily Value. — USDA FNDDS food code 41203030, household measure 1 cup = 231 g, quantity not specified = 116 g Evidence E source
  Per 231 g: 217 calories, 7.1 g protein, 7.9 g fiber, 809 mg sodium, 487 mg potassium, 2.1 mg iron

What your body absorbs

• In a crossover RCT of 10 young and 10 older adults eating 20 g protein, lysine and threonine uptake from black beans did not differ by age, while it was 19% lower in older adults for sorghum. — 10 young (about 22 y) and 10 older (about 73 y) adults, 20 g labeled protein from milk, sorghum or black beans, dual tracer (n = 20) Evidence B source
  Older vs young plasma-to-meal ratio: sorghum -19% (P = 0.041); black beans no difference (P = 0.849)
• In a stable-isotope crossover trial in 22 women with low iron status, iron absorption from control bean meals was 9.2%, and with phytic acid removed, iron absorbed from biofortified beans was up to 51% higher than from control beans. — 22 Rwandese women with low iron status, composite bean meals with potatoes or rice, native vs 50% and >95% dephytinised beans (n = 22) Evidence B source
  Fractional absorption 9.2% from control bean meals; iron absorbed from biofortified beans 406 ug native, 599 ug (50% dephytinised), 746 ug (>95%)

What cooking and storage change

• By the USDA retention table for legumes, beans boiled 2 to 2.5 hours and drained keep 30% of folate, 40% of thiamin, 65% of potassium and 75% of iron. — USDA Table of Nutrient Retention Factors Release 6, group Legumes and Legume Products, code 541 Evidence E source
  Code 541: folate 30%, thiamin 40%, vitamin B6 50%, potassium 65%, magnesium 70%, iron 75%

What it does to your health

• By a meta-analysis of 38 trials in 2095 people, whole pulses lowered LDL cholesterol by 5.4 mg/dL (0.14 mmol/L), and for beans the drop grew with intake up to 1 cup a day. — Participants of 38 randomized trials (52 comparisons) of whole dietary pulses lasting at least 3 weeks, median 130 g/d for 6 weeks (n = 2095) Evidence A source
  LDL MD -5.4 mg/dL (95% CI -7.3 to -3.1; metric: -0.14 mmol/L, -0.19 to -0.08); beans -9.7 mg/dL (-0.25 mmol/L) per 0.5 cup (-0.48 to -0.02) up to 1 cup/d
• In a crossover RCT of 12 women, adding black beans to white rice at 50 g carbohydrate lowered blood glucose at 60, 90 and 120 minutes versus rice alone. — 12 healthy adult women aged 18-65, three test meals of 50 g available carbohydrate at least 7 days apart (n = 12) Evidence B source
  Glucose lower vs rice at 60 min (p = 0.026), 90 min (p = 0.001) and 120 min (p = 0.024) for the black bean meal
• In a pilot crossover RCT of 8 healthy adults, LDL cholesterol was lower 6 hours after 3/4 cup of black beans than after the same portion of rice. — 8 healthy adults, single-blinded randomized crossover, 3/4 cup of beans or rice (n = 8) Evidence B source
  LDL lower at 6 h after black beans vs rice (p < 0.05); size not in abstract

Safety, limits and interactions

• The FDA advises never leaving foods that need refrigeration, including leftovers, at room temperature for more than two hours, or one hour above 90 F. — US consumers, home food storage Evidence E source
  2 h limit at room temperature, 1 h above 90 F

Who this works differently for

• In a crossover RCT of 17 adults with type 2 diabetes, black beans with rice gave a lower glucose area than rice alone at 50 g carbohydrate. — 17 men and women aged 35-70 with type 2 diabetes, 4x4 crossover, meals matched for 50 g available carbohydrate (n = 17) Evidence B source
  IAUC significantly lower for pinto and black bean/rice vs rice; not for kidney beans
• In a crossover RCT of 12 adults with metabolic syndrome, a meal with black beans lowered insulin over 5 hours more than meals matched for fiber or antioxidants. — 12 adults with metabolic syndrome, three Western-style meals (black bean, fiber matched, antioxidant matched), 5 h postprandial (n = 12) Evidence B source
  Insulin lower after black bean meal vs fiber-matched or antioxidant-matched meals (p < 0.0001); size not in abstract
• In a crossover RCT of 35 adults aged about 72, a breakfast with 135 g black beans gave satiety and 24-hour energy intake not different from 80 g beef. — 35 older adults, age 72.4 years, BMI 25.1, breakfast tortilla with black beans (135 g), red kidney beans (135 g) or beef (80 g) (n = 35) Evidence B source
  Appetite AUCs, ad libitum lunch and 24-h energy intake not significantly different between meals

What is still unknown

• In a crossover pilot RCT of 9 adults with stiff arteries, 3/4 cup of wheat berries lowered the augmentation index at 2 hours while black beans did not. — 9 adults aged 50-64 (3 men, 6 women) with established arterial stiffness, 3/4 cup black beans, wheat berries or white rice (n = 9) Evidence B source
  Augmentation index 26.1% to 16.2% after wheat, no change after beans or rice

The bottom line

The human data on black beans themselves come from short test meals. In 12 healthy women, black beans added to white rice at 50 g carbohydrate kept blood glucose lower at 60, 90 and 120 minutes than rice alone. In 17 adults with type 2 diabetes, black beans with rice gave a lower total glucose area than rice alone. In 12 adults with metabolic syndrome, a meal with black beans lowered insulin over 5 hours more than meals matched for fiber or antioxidants, and the abstract gives no size. In 8 healthy adults, LDL cholesterol was lower 6 hours after 3/4 cup of black beans than after rice. None of these trials lasted longer than a day. In 35 adults aged about 72, a breakfast with 4.8 oz (135 g) of black beans gave satiety and 24-hour energy intake that did not differ significantly from a breakfast with 2.8 oz (80 g) of beef. In 10 young and 10 older adults eating 20 g of protein, uptake of lysine and threonine from black beans did not differ by age, while for sorghum it was 19% lower in the older group. In 9 adults aged 50 to 64 with stiff arteries, 3/4 cup of wheat berries lowered the augmentation index at 2 hours and black beans did not. Iron from beans is poorly absorbed. In 22 Rwandan women with low iron status, 9.2% of the iron in ordinary bean meals was absorbed. Removing almost all the phytic acid with enzymes let them absorb 51% more iron from biofortified beans than from the ordinary ones. Those were not black beans specifically, and the phytic acid was removed with enzymes in a lab. By the USDA retention factor for legumes boiled 2 to 2.5 hours and drained, about 30% of folate, 40% of thiamin, 65% of potassium and 75% of iron stay in the bean. That factor covers the legume group as a whole and dates from 1975. Beans are cheap protein. In a New Zealand supermarket survey at 2019 prices, dried legumes cost NZ$0.30 per 3.5 oz (100 g), against NZ$2.57 for other meat-free products. Who should be careful. The practical risk is storage. The FDA says foods that need refrigeration should never sit at room temperature for more than two hours, or one hour above 90 F, and a salad of cooked beans is one of them. If you watch your sodium, the 809 mg in a cup of the survey recipe is the number to note. We found no source on allergy, pregnancy or medicines for this dish.

Sources

1. bbsl-daily-r3-01 · reference dataset
   41203030 Black bean salad | Energy 94 KCAL | Protein 3.08 G | Total lipid (fat) 3.85 G | Fiber, total dietary 3.4 G | Sodium, Na 350 MG | Potassium, K 211 MG | Iron, Fe 0.9 MG | Vitamin C, total ascorbic acid 4.4 MG | Folate, total 35 UG
   USDA FNDDS, food code 41203030 Black bean salad · checked 2026-09-29
2. bbsl-daily-r3-13 · cross-sectional
   Dried legumes were the cheapest plant protein (mean ± SD) purchase price = NZ $0.30 ± 0.16/100 g), compared with 'other' meat-free products (purchase price = NZ $2.57 ± 0.88/100 g). The most common nutrition claims on meat analogues were about protein content. Dietary fibre claims were the most common on canned and dried legumes.
   Nutr Diet, 2023 · checked 2026-09-29
3. bbsl-daily-r3-02 · reference dataset
   41203030 Black bean salad | 1 cup 231 g | Quantity not specified 116 g | Energy 94 KCAL per 100 g | 217.1 KCAL per 1 cup | Sodium, Na 350 MG per 100 g
   USDA FNDDS, food code 41203030 Black bean salad · checked 2026-09-29
4. bbsl-daily-r3-09 · RCT
   The isotope plasma-to-meal ratio for lysine and threonine was 19% lower in older adults compared with young adults for sorghum (P = 0.041), whereas it was not significantly different for milk (P = 0.277) and black beans (P = 0.849).
   Am J Clin Nutr, 2026 · checked 2026-09-29
5. bbsl-daily-r3-10 · RCT
   With native PA concentrations, fractional iron absorption from the control bean meals was 9.2%, 30% higher than that from the biofortified bean meals (P < 0.001). ... With ∼50% and >95% dephytinization, the quantity of iron absorbed from the biofortified bean meals increased to 599 and 746 μg, respectively, which was 37% (P < 0.005) and 51% (P < 0.0001) higher than from the control bean meals.
   J Nutr, 2014 · checked 2026-09-29
6. bbsl-daily-r3-03 · reference dataset
   USDA-RETN-R6:541 | LEGUMES,CKD 2/2.5HRS,BOILED,DRAINED | folate_total_ug 30% | thiamin_mg 40% | vitamin_b6_mg 50% | potassium_mg 65% | magnesium_mg 70% | iron_mg 75%
   USDA Table of Nutrient Retention Factors, Release 6 (2007), code 541 · checked 2026-09-29
7. bbsl-daily-r3-04 · meta-analysis
   Thirty-eight trials (52 trial comparisons, n=2095) with a median of 6 weeks and dose of 130 g/d (0.5-0.67 cup/d) showed that whole dietary pulses decreased low-density lipoprotein-cholesterol (mean difference, -0.14 mmol/L [95% CI, -0.19 to -0.08]) ... A linear inverse relationship was shown for beans up to 1 cup/d for low-density lipoprotein-cholesterol (coefficient, -0.25 mmol/L/0.5 cup [95% CI, -0.48 to -0.02])
   J Am Heart Assoc, 2026 · checked 2026-09-29
8. bbsl-daily-r3-05 · RCT
   Changes in blood glucose concentrations were significantly different for the black bean meal and the chickpea meal in comparison to rice alone at 60 min (p = 0.026 and p = 0.024), 90 min (p = 0.001 and p = 0.012) and 120 min post prandial (p = 0.024; black bean meal).
   Nutrients, 2017 · checked 2026-09-29
9. bbsl-daily-r3-11 · RCT
   LDL-cholesterol concentrations were lower 6 h after black bean consumption compared to rice (p < 0.05).
   Nutr Metab Cardiovasc Dis, 2021 · checked 2026-09-29
10. bbsl-daily-r3-14 · agency guidance
    Never allow meat, poultry, seafood, eggs, or produce or other foods that require refrigeration to sit at room temperature for more than two hours—one hour if the air temperature is above 90° F.
    US FDA, Are You Storing Food Safely? (consumer update) · checked 2026-09-29
11. bbsl-daily-r3-06 · RCT
    Incremental area under the curve values were significantly lower for the pinto and black bean/rice meals compared to rice alone, but not for kidney beans.
    Nutr J, 2012 · checked 2026-09-29
12. bbsl-daily-r3-07 · RCT
    Insulin was lower after the BB meal, compared to the FM or AM meals (p < 0.0001).
    Nutrients, 2015 · checked 2026-09-29
13. bbsl-daily-r3-08 · RCT
    Appetite sensation AUCs, ad libitum pizza intake, and 24-h energy intake did not significantly differ between the test meals.
    J Nutr, 2025 · checked 2026-09-29
14. bbsl-daily-r3-12 · RCT
    A marked decline in augmentation index at 75 bpm (arterial stiffness) from 26.1 ± 3.6% to 16.2 ± 2.0% was observed 2 h after eating whole wheat but not beans or white rice.
    Nutrients, 2025 · checked 2026-09-29