Bean paste: sweet red paste and salty miso are two different foods

A white bun filled with sweet red bean paste scored a glycemic index of 58 in 19 healthy young men in Singapore, the same as a plain steamed bun, and that figure is for the whole bun with the paste never tested alone. The name also covers fermented soybean pastes such as Japanese miso and Korean doenjang, and salt is where the two part ways. Sweetened bean paste has 124 mg of sodium per 3.5 oz (100 g) in US survey tables and miso has 3728 mg, so a 12 g portion of miso carries about 447 mg, recalculated figures with no spread and no separate entry for doenjang. The other trials are on the fermented kind. In 40 Japanese adults aged 40 to 69 with high-normal blood pressure or stage 1 hypertension, 1.1 oz (32 g) of miso a day for 8 weeks lowered night-time blood pressure against a soy food control and left daytime clinic readings unchanged. The size of that drop is not in the abstract, and the miso was two varieties from one maker carrying 3.8 g of salt a day.

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

How much is actually in it

• A white bun filled with red bean paste has a medium glycemic index of 58, the same as a plain steamed bun. — Healthy young Chinese and Indian men, Singapore, randomized crossover GI testing (n = 19) Evidence B source
  GI 58 (SEM 4) red bean bun vs 58 (SEM 3) plain steamed bun

What a real portion looks like

• Sweet bean paste and salty soybean paste are nutritionally different foods: sweetened bean paste has 124 mg sodium per 3.5 oz (100 g), while miso has 3728 mg, so a 12 g portion of miso gives about 450 mg. — FNDDS: Bean paste, sweetened (91407150, FDC 2710309); Miso (FDC 2707439) (n = 2 records) Evidence E source
  Sweet bean paste per 3.5 oz (100 g): 226 calories, protein 6.22 g, sodium 124 mg, 1 tbsp = 20 g; miso: sodium 3728 mg per 3.5 oz (100 g), 447 mg per 12 g

What your body absorbs

• Iron added to a corn tortilla and black bean paste meal is poorly absorbed: teenage girls took up about 5.5% from ferrous sulfate and 9.0% from NaFeEDTA. — Guatemalan girls aged 12-13 y, stable-isotope test meals Evidence B source
  Iron bioavailability 5.5% (ferrous sulfate) vs 9.0% (NaFeEDTA), P = 0.009

What cooking and storage change

• In Korean market foods, soybean paste and soy sauce supplied 91% of dietary aflatoxin B1 exposure, although most samples were under the legal limit. — 694 food samples from six regions of South Korea (n = 694 samples) Evidence C source
  AFB1 in 4.6% of samples, up to 48.6 ug/kg; soybean paste and soy sauce 91% of exposure

What it does to your health

• In a randomized trial, 1.1 oz (32 g) of miso a day for 8 weeks lowered night-time blood pressure in adults with high-normal pressure, without changing daytime readings. — Adults 40-69 y with high-normal BP or stage I hypertension, Japan, 8 weeks (n = 40) Evidence B source
  Nighttime BP decreased vs soy food control; daytime clinical BP unchanged
• Taking about 10 g of doenjang a day for 12 weeks did not reduce visceral fat compared with placebo in overweight Korean adults. — Overweight adults (BMI 23 or more), Korea, 12 weeks (n = 51) Evidence B source
  No significant effect on visceral fat area overall; reduction only in UCP-1 G allele carriers
• Across 52 observational studies, eating a lot of soy paste was not linked with overall cancer risk (RR 1.00), unlike tofu and soymilk, which were linked with lower risk. — 17 cohort and 35 case-control studies to October 2023 (n = 52 studies) Evidence C source
  Soy paste RR 1.00 (0.88 to 1.14); miso soup 0.99 (0.87 to 1.12); tofu 0.78 (0.70 to 0.86)

Safety, limits and interactions

• Prospective studies link high miso soup intake in men with 17% higher gastric cancer risk, while non-fermented soy foods are linked with lower risk. — 13 prospective studies, 517,106 participants, 5800 cases (n = 13 studies) Evidence C source
  Miso soup men RR 1.17 (1.02 to 1.36); nonfermented soy RR 0.63 (0.50 to 0.79)
• In a Japanese cohort of 42,535 adults, miso soup was the one salty food linked with higher risk of mouth, throat and esophageal cancers. — JACC Study, Japanese adults aged 40-79, median 14.4 years (n = 42,535) Evidence C source
  Highest vs lowest salt tertile HR 1.67 (1.08 to 2.61); miso soup positively associated
• The FDA label for transdermal selegiline (EMSAM) at 9 mg/24 h or more puts most soybean products on the tyramine avoid list, naming soy sauce and tofu. A soybean paste is in that class, a paste from other beans is not named. — Adults using EMSAM (selegiline transdermal system) at 9 mg/24 h or 12 mg/24 h (n = -) Evidence E source
  Avoid list in label Table 5, miscellaneous class

Who this works differently for

• In overweight Koreans taking 9.8 g of doenjang a day for 12 weeks, visceral fat fell more in carriers of one PPAR-gamma2 gene variant than in non-carriers, and insulin resistance markers rose in the doenjang group. — Overweight Koreans, 60 randomized, 51 completers, 12 weeks (n = 51) Evidence B source
  VFA decreased in T allele carriers vs C allele; HOMA-IR increased in doenjang group
• NIH's kidney institute names some seasonings and soy and teriyaki sauces as high in sodium. It restates the US Dietary Guidelines limit of no more than 2,300 mg of sodium a day for adults, and says many people with chronic kidney disease need to limit sodium even more. — adults, people with chronic kidney disease Evidence E source
  Adults: no more than 2,300 mg sodium per day (DGA 2020-2025); many people with CKD need a lower limit set by their clinician

What is still unknown

• Pooled cohort data found no link between miso intake and death rates, unlike cheese and fermented milks. — 50 prospective cohort studies, over three million adults (n = 50 studies) Evidence C source
  Miso: no significant association with all-cause, CVD or cancer mortality

The bottom line

In 51 overweight Korean adults, about 10 g of doenjang a day for 12 weeks had no significant effect on visceral fat against placebo, with a drop only in carriers of one gene variant. In a trial of 9.8 g a day in capsule form over 12 weeks, visceral fat fell only in carriers of a PPAR-gamma2 variant, and insulin and HOMA-IR rose in the doenjang group. Across 52 observational studies, soy paste showed no link with overall cancer risk (RR 1.00, 0.88 to 1.14), and pooled cohorts of over three million adults found no association between miso and death rates. Iron added to a meal of corn tortilla and black bean paste was poorly absorbed in a fortification test. Guatemalan girls aged 12 and 13 absorbed 5.5% of the iron added as ferrous sulfate and 9.0% as NaFeEDTA, with the paste itself never separated from the meal. Who should be careful. Across 13 prospective studies, high miso soup intake in men went with a 17% higher risk of stomach cancer (RR 1.17, 1.02 to 1.36), and those studies could not separate the salt from the paste. In a Japanese cohort of 42,535 adults followed for a median 14.4 years, miso soup was the one salty food associated with more mouth, throat and esophageal cancers, from only 145 cases. In 694 Korean market samples tested in 2007, soybean paste and soy sauce supplied 91% of dietary aflatoxin B1 exposure, and the modeled excess liver cancer risk was higher in people with hepatitis B. For people using the selegiline skin patch EMSAM at 9 mg/24 h or more, the FDA label lists most soybean products, including soy sauce and tofu, among the foods to avoid for tyramine, and miso and doenjang are soybean pastes. NIH's kidney institute restates the 2020-2025 US Dietary Guidelines limit of no more than 2,300 mg of sodium a day for adults and says many people with chronic kidney disease need to limit sodium even more, so miso counts as a salty food against that limit.

Sources

1. bnp-daily-r1-06 · randomized crossover trial
   Asian breakfast foods were of medium (white bun filled with red bean paste=58 (sem 4); Chinese steamed white bun=58 (sem 3))
   Br J Nutr, 2018 · checked 2026-09-29
2. bnp-daily-r1-01 · USDA FNDDS, dataset
   Bean paste, sweetened (FNDDS 91407150, FDC 2710309): Energy 226 kcal, Protein 6.22 g, Sodium, Na 124 mg per 100 g; 1 tablespoon = 20 g; Miso (FDC 2707439): Sodium, Na 3728 mg per 100 g; Quantity not specified = 12 g = 447.4 mg
   USDA FNDDS, FDC 2710309 and FDC 2707439 · checked 2026-09-29
3. bnp-daily-r1-02 · randomized crossover trial
   Geometric mean iron bioavailability from test meals fortified with ferrous sulfate was 5.5% and was significantly higher in test meals fortified with NaFeEDTA (9.0%; P = 0.009, paired t test).
   Am J Clin Nutr, 2002 · checked 2026-09-29
4. bnp-daily-r1-10 · food contaminant survey
   The major contributors to the dietary intake of AFB1 were soybean paste and soy sauce, which composed 91% of the total exposure to AFB1. ... The excess risk of liver cancer for those exposed to AFB1 through food intake was estimated to be 5.78 x 10(-6) for hepatitis B-negative individuals and 1.48 x 10(-4) for hepatitis B-positive individuals.
   J Food Prot, 2007 · checked 2026-09-29
5. bnp-daily-r1-03 · randomized controlled trial
   A total of 40 subjects aged 40-69 years with high-normal BP or stage I hypertension were randomly assigned to two groups: 1) the miso group (32 g 2:1 w/w Nenrin and MK-34-1 with 3.8 g salt/day) or 2) the control soy food group (14.4 g soy food with 0.2 g salt/day). ... Compared with the soy food intake, miso intake for 8 weeks did not affect daytime clinical BP but significantly decreased nighttime BP without affecting pulse rate (PR).
   Hypertens Res, 2019 · checked 2026-09-29
6. bnp-daily-r1-04 · randomized controlled trial
   Supplementation of doenjang had no significant effect on the visceral fat area compared with that of the placebo group, but there was a significantly reduced amount of visceral fat in subjects with the G allele of UCP-1 polymorphism.
   Nutr Res, 2012 · checked 2026-09-29
7. bnp-daily-r1-08 · meta-analysis of observational studies
   soy paste (RR: 1.00; 95% CI: 0.88, 1.14), miso soup (RR: 0.99; 95% CI: 0.87, 1.12), or natto (RR: 0.96; 95% CI: 0.82, 1.11) and cancer risk.
   Nutrients, 2024 · checked 2026-09-29
8. bnp-daily-r1-07 · meta-analysis of cohort studies
   high intake of total soy food (the highest vs the lowest category: RR: 0.78, 95% CI: 0.62-0.98) and nonfermented soy food (RR: 0.63, 95% CI: 0.50-0.79) were inversely associated with GC risk, while high intake of miso soup was associated with the risk in male (RR: 1.17, 95% CI: 1.02-1.36).
   Medicine (Baltimore), 2017 · checked 2026-09-29
9. bnp-daily-r1-09 · prospective cohort
   the multivariable HR for the highest v. lowest tertiles of salt consumption was 1·67 (95 % CI: 1·08, 2·61, P-trend = 0·01). ... Among the salt sources, miso soup consumption was positively associated with the combined risk of oral, pharyngeal and oesophageal cancers; however, the consumption of other high-salt foods was not.
   Br J Nutr, 2026 · checked 2026-09-29
10. sf-tymaoi-22 · agency advice
    Concentrated yeast extract (e.g., Marmite), sauerkraut, most soybean products (including soy sauce and tofu)
    EMSAM (selegiline transdermal system), FDA-approved label, sections 2.3 and 7.2 (Table 5) · checked 2026-10-08
11. bnp-daily-r1-05 · randomized controlled trial
    Sixty overweight subjects were randomly assigned to consume either 9.8 g/day of doenjang or placebo for 12 weeks. ... Visceral fat area (VFA) was significantly decreased by doenjang supplementation in subjects with a mutant T allele of PPAR-γ2 compared to those with a C allele after adjusting for age, sex, and body mass index. Plasma free fatty acid, insulin, and homeostatic model assessment insulin resistance (HOMA-IR) levels were also significantly increased in the doenjang group.
    J Med Food, 2014 · checked 2026-09-29
12. sf-na-r6-5 · agency advice
    Table salt, some seasonings, ketchup, mustard, and certain sauces such as barbecue, soy, and teriyaki sauces are high in sodium. The 2020–2025 Dietary Guidelines for Americans recommends adults limit their sodium to no more than 2,300 milligrams per day. Many people with CKD need to limit their sodium even more. Your health care professional can determine your sodium limit, based on your kidney health.
    NIDDK (NIH), Eating Right for Chronic Kidney Disease · checked 2026-10-08
13. bnp-daily-r1-11 · meta-analysis of cohort studies
    Miso and bread consumption showed no significant associations with mortality.
    Front Nutr, 2026 · checked 2026-09-29