Bean sprouts: a food whose whole research record is about not getting sick

Bean sprouts are unusual in that almost everything published about them is food safety. We found no randomised trial that feeds bean sprouts to anyone, so nothing on this page rises above observational evidence, and the observations are outbreaks. In the largest Salmonella Newport outbreak recorded in Germany, 106 cases in October and November 2011, sprouts were the only food linked to infection, at an odds ratio of 18.4 with a confidence interval of 2.2 to 150.2. That interval is so wide because the comparison group were other Salmonella patients rather than healthy people. A British outbreak the year before reached 231 laboratory-confirmed cases of Salmonella Bareilly, and the investigators concluded that getting people to cook raw bean sprouts properly was the main way to prevent further cases. That report gives no effect size. Cooking, which the FDA advises for safety, costs about half the vitamin C, 13.2 mg per 100 g raw against 6.3 mg cooked, in USDA records built from recipes and retention factors rather than from one batch measured twice. A US cup of raw sprouts weighs 90 g and carries about 11.9 mg.

What a real portion looks like

• A US cup of raw bean sprouts weighs 90 g and carries about 11.9 mg vitamin C, while an unspecified serving is recorded as 45 g. — USDA FNDDS 2021-2023 household measures, United States (n = 1 food, 2 measures) Evidence E source
  1 cup 90 g = 11.9 mg vitamin C; quantity not specified 45 g = 5.9 mg

What cooking and storage change

• A 2010 UK outbreak of Salmonella Bareilly with 231 laboratory-confirmed cases was linked to bean sprouts, and investigators concluded that cooking raw bean sprouts correctly was the main way to prevent further cases. — 231 laboratory-confirmed S. Bareilly cases, United Kingdom, August to November 2010 (n = 231) Evidence C source
  Bean sprout consumption significantly associated with illness in a case-control study (numbers not given in abstract)
• A 2026 systematic review of 146 studies found that sprout contamination usually starts in the seed, that hypochlorite and hydrogen peroxide washes cut microbial load but miss bacteria inside biofilms, and that combining several disinfection methods works best. — 146 laboratory and processing studies of edible sprout disinfection, 2010 to 2024 (n = 146 studies) Evidence D source
  No pooled number; qualitative comparison of chemical and non-chemical seed and sprout disinfection
• In USDA FNDDS, cooked bean sprouts hold 6.3 mg vitamin C per 100 g against 13.2 mg raw, so cooking, which FDA advises for safety, costs about half the vitamin C. — USDA FNDDS 2021-2023 food codes for bean sprouts raw and cooked (n = 2 food codes) Evidence E source
  Vitamin C 13.2 mg/100 g raw (fdc_id 2709768) vs 6.3 mg/100 g cooked (fdc_id 2709871), about -52%

What it does to your health

• In a Japanese case-control study of 278 COPD patients and 340 controls, the highest quartile of total soybean product intake had 61% lower odds of COPD (OR 0.392, 95% CI 0.194 to 0.793), with similar patterns for soy foods such as tofu and bean sprouts. — 278 COPD patients aged 50 to 75 and 340 community controls, central Japan, 2006 (n = 618) Evidence C source
  Adjusted odds ratio 0.392 (95% CI 0.194-0.793) for highest vs lowest quartile of total soybean products, p for trend 0.001; odds, not risk

Safety, limits and interactions

• In the largest Salmonella Newport outbreak recorded in Germany (106 cases, 2011), eating sprouts was the only food linked to infection, with an odds ratio of 18.4 (95% CI 2.2 to 150.2), and mung bean sprouts from one Dutch producer were the traced source. — 50 adult S. Newport cases versus 45 S. Enteritidis cases, Germany, October to November 2011 (n = 106 outbreak cases; 50 vs 45 in case-control) Evidence C source
  Odds ratio 18.4 (95% CI 2.2-150.2) for sprout consumption; this is an odds ratio from a case-case comparison
• Seven Salmonella Enteritidis outbreaks in 2000 to 2002 in the United States, Canada and the Netherlands were traced to raw mung bean sprouts, and none of the implicated growers disinfected seeds at recommended concentrations. — outbreak of SE infections linked to raw mung bean sprouts in 2000 plus six similar outbreaks 2000-2002 (n = 7 outbreaks) Evidence C source
  All outbreaks due to unusual phage types of S. Enteritidis; outbreak strain found in spent irrigation water and a drain at one grower

Who this works differently for

• Mung bean sprouts can cause pollen-food allergy in people sensitised to birch, because mung bean carries the PR-10 allergen Vig r1, as shown in two Japanese patients with lip swelling and oral discomfort who were positive for birch, Gly m4 and Bet v1 IgE. — two patients (a teenage girl and a man in his twenties), Japan (n = 2) Evidence C source
  Prick-to-prick test positive for mung bean sprouts in both; both IgE-positive to birch, Gly m4 and Bet v1
• Among 81 pregnant Australian women, 68.7% of those aware of listeriosis advice had cut or avoided alfalfa and bean sprouts, versus 28.5% of those unaware (p = 0.006). — 81 pregnant women recruited from antenatal clinics, Australia, surveyed at 10 to 23 weeks (n = 81) Evidence C source
  Reduced or avoided sprouts: 68.7% aware vs 28.5% unaware, p = 0.006
• The FDA tells pregnant women to avoid raw sprouts of any kind, including mung bean sprouts, and to cook sprouts thoroughly, because bacteria inside the seed grow to high levels during sprouting even under clean conditions. — FDA Food Safety for Moms-to-Be guidance, page addressed to pregnant women Evidence E source
  Advice: avoid raw sprouts, cook thoroughly; no numeric risk given

The bottom line

Buy them, cook them, eat them. Sprouting needs warmth and water, which is also what the bacteria on the seed need. A 2026 review of 146 laboratory and processing studies found that contamination usually starts in the seed itself, and that hypochlorite and hydrogen peroxide washes lower the microbial load but do not reach bacteria protected inside biofilms. That review is about what producers do, not about your colander. Seven Salmonella Enteritidis outbreaks in the United States, Canada and the Netherlands between 2000 and 2002 were traced to raw mung bean sprouts, and none of the growers involved disinfected seeds at the recommended concentrations. For pregnancy the FDA is blunt. Its advice is to avoid raw sprouts of any kind, mung bean included, and to cook sprouts thoroughly, because bacteria inside the seed multiply during sprouting even when everything is clean. Among 81 pregnant Australian women surveyed between 10 and 23 weeks, 68.7 percent of those who knew the listeriosis advice had cut back or dropped alfalfa and bean sprouts, against 28.5 percent of those who did not know it, p equals 0.006. That was one clinic and behaviour the women reported themselves. One allergy signal exists and it is small. Two Japanese patients, a teenage girl and a man in his twenties, had lip swelling and oral discomfort from mung bean sprouts. Both carried IgE to birch, Bet v 1 and Gly m 4, and mung bean holds the related PR-10 allergen Vig r 1. The authors of that report note how few such cases have appeared in a country where these sprouts are everyday food. You may have heard that sprouts protect the lungs. The study behind that compared 278 Japanese COPD patients with 340 community controls, and found 61 percent lower odds of COPD in the top quartile of total soybean product intake. Those are odds rather than risk, sprouts were pooled with tofu and the rest, and diet was recalled after the diagnosis.

Sources

1. bsp-dv2-10 · reference dataset
   FNDDS Bean sprouts, raw (code 75101000, fdc_id 2709768): 1 cup 90 g, 11.9 MG vitamin C · Quantity not specified 45 g, 5.9 MG
   USDA FNDDS 2021-2023 · checked 2026-09-23
2. bsp-dv2-02 · case-control
   Between August and November 2010, there were 231 laboratory-confirmed reports of S. Bareilly in the United Kingdom. A case–control study showed that consumption of bean sprouts was significantly associated with illness. The investigation concluded that raising public awareness to ensure the correct preparation of raw bean sprouts during cooking was the principal means of preventing further cases.
   Euro Surveill, 2010 · checked 2026-09-23
3. bsp-dv2-07 · qualitative systematic review
   Primary sprout contamination usually occurs through seeds and post-harvest washing...In this systematic review, 146 studies published between 2010 and 2024 were evaluated, and the effectiveness of different chemical and non-chemical disinfection methods was investigated...There are concerns about chemical residues and their effectiveness against pathogens internalized or protected in biofilms is limited.
   Plant Foods Hum Nutr, 2026 · checked 2026-09-23
4. bsp-dv2-09 · reference dataset
   FNDDS Bean sprouts, raw (fdc_id 2709768): Vitamin C, total ascorbic acid 13.2 MG per 100 g · Bean sprouts, cooked (fdc_id 2709871): Vitamin C, total ascorbic acid 6.3 MG per 100 g
   USDA FNDDS 2021-2023 · checked 2026-09-23
5. bsp-dv2-05 · case-control
   A total of 278 eligible patients (244 men and 34 women), aged 50-75 years with COPD diagnosed within the past four years, were referred by respiratory physicians, while 340 controls (272 men and 68 women) were recruited from the community...A significant reduction in COPD risk was evident for highest versus lowest quartile of daily intake of total soybean products, with adjusted odds ratio (OR) 0.392, 95% CI 0.194-0.793, p for trend 0.001. Similar decreases in COPD risk were associated with frequent and higher intake of soy foods such as tofu and bean sprouts
   Respir Res, 2009 · checked 2026-09-23
6. bsp-dv2-01 · case-control
   The largest Salmonella enterica serovar Newport outbreak (n=106) ever reported in Germany occurred in October and November 2011...In multivariable logistic regression analysis, only sprout consumption was significantly associated with S. Newport infection (odds ratio: 18.4; 95% confidence interval: 2.2-150.2). Molecular typing patterns of human isolates were indistinguishable from a mung bean sprouts isolate.
   Euro Surveill, 2014 · checked 2026-09-23
7. bsp-dv2-03 · case-control and environmental investigation
   We investigated an outbreak of Salmonella Enteritidis (SE) infections linked to raw mung bean sprouts in 2000 with two case-control studies and reviewed six similar outbreaks that occurred in 2000-2002...None of the growers disinfected seeds at recommended concentrations.
   Epidemiol Infect, 2009 · checked 2026-09-23
8. bsp-dv2-04 · case report
   Both patients were positive for IgE specific to birch, Gly m4, and Bet v1.Mung beans belong to the PR-10 family because they contain the allergenic component, Vig r1. A cross reaction to mung bean may occur in a patient with birch allergy as in the present cases. Mung bean sprouts are a cheap and common dietary item in Japan where, however, only a few cases of mung bean sprouts allergy have been reported.
   Arerugi, 2023 · checked 2026-09-23
9. bsp-dv2-06 · cross-sectional
   Pregnant women (n=81) were recruited from antenatal clinics...The proportion of women who decreased or avoided consumption of certain high-risk Listeriosis foods were higher in those who were aware compared with those who were unaware of Listeriosis recommendations [raw fish (96.0 vs 69.2%, p=0.046), soft-serve ice cream (93.9 vs 58.3%, p=0.004) and alfalfa/bean sprouts (68.7 vs 28.5%, p=0.006)].
   Women Birth, 2019 · checked 2026-09-23
10. bsp-dv2-08 · agency guidance
    Avoid eating raw sprouts of any kind (including alfalfa, clover, radish, and mung bean)...Cook sprouts thoroughly. This significantly reduces the risk of illness.
    FDA, Fruits, Veggies and Juices (Food Safety for Moms-to-Be), 2024 · checked 2026-09-23