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Does cabbage soup help with weight loss?

We found no trial of the cabbage soup diet, and none of cabbage itself on body weight. The tested questions nearby are about soup and about very fast dieting. A meta-analysis of 38 studies found that meals with lower energy density, a median 1.1 calories per gram against 1.5, cut intake by 223 calories per meal (95% CI 186.0 to 259.7), mostly in single lab meals that did not measure weight. In a one-year randomized trial of 200 overweight adults on a reduced-calorie plan, two servings of low-calorie soup a day went with 16 lb (7.2 kg) lost, against 11 lb (4.8 kg) for the same calories as snacks. The group with no special food lost 18 lb (8.1 kg), so soup did not beat the plain diet.

Unsettled. Whether the cabbage soup diet works is unknown, because we found no study of it. What has been tested points two ways. Soup that replaces higher-calorie food helps a calorie-controlled diet. Very fast weight loss on very-low-calorie diets is not kept any better a year later.

Kilograms lost in one year on a calorie-reduced diet
0246810Diet with no special food1-year trial, 200 overweight adults8.1Diet with no special food: 8.1 kg (95% CI 8.1 to 8.1)Diet plus two soups a daysame trial, same calories7.2Diet plus two soups a day: 7.2 kg (95% CI 7.2 to 7.2)Diet plus one soup a daysame trial6.1Diet plus one soup a day: 6.1 kg (95% CI 6.1 to 6.1)Diet plus two snacks a daysame trial, same calories4.8Diet plus two snacks a day: 4.8 kg (95% CI 4.8 to 4.8)

Everyone was on the same dietitian-led reduced-calorie plan. Two soups beat two snacks, and soup did not beat the plain diet. The paper reports standard errors, not confidence intervals, so none are drawn. Source: card ev-cabw-02 below.

What the trials found

Soup with a meal

Meals that pack fewer calories into each gram make people eat less at that meal, while they eat the same weight of food. That is the finding of the 38-study meta-analysis, with high heterogeneity between studies, and it measured intake at single meals. In a crossover trial of 60 normal-weight adults, a low-calorie soup eaten 15 minutes before a lab lunch cut energy eaten at the meal by 20 percent, 134 calories (plus or minus 25). Broth, chunky and pureed soups did equally well. Body weight was not measured in either.

Soup inside a diet

The one long trial put 200 overweight and obese adults on the same dietitian-led reduced-calorie plan for a year. Two soups a day went with 16 lb (7.2 kg) lost and two snacks with the same calories with 11 lb (4.8 kg). One soup a day gave 13 lb (6.1 kg), which did not differ significantly from any other group. The plain diet group lost the most, 18 lb (8.1 kg). So soup helped against high-calorie snacks, inside an overall calorie plan, and added nothing to the plan on its own.

Adding vegetables

Two meta-analyses of randomized trials disagree on size. One found that advice or provision to eat more fruit and vegetables, without cutting other foods, had no measurable effect on weight (standardized difference 0.04, 95% CI -0.10 to 0.17, in 7 studies). Few trials were eligible. The other pooled 8 trials with 1,026 people over an average 14.7 weeks and found 1.2 lb (0.54 kg) more lost in the higher-intake arms (95% CI 0.09 to 2.3 lb (0.04 to 1.05 kg)), with high heterogeneity. Energy intake did not fall significantly in those arms. Read together, vegetables do little for weight unless they take the place of other calories.

Fast loss, and what happens after

Cabbage soup diets are sold on fast results. A meta-analysis of 6 randomized trials compared diets under 800 calories a day with standard low-calorie diets in adults with obesity. The very-low-calorie diets took off 16.1 percent of starting weight early, against 9.7 percent. A year or more later the figures were 6.3 and 5.0 percent, a gap that was not significant. These were medically supervised formula diets, so they speak to a home soup diet only by analogy.

Percent of starting weight lost, fast diet against standard diet
05101520Very-low-calorie diet, early6 trials, adults with obesity16.1Very-low-calorie diet, early: 16.1 percent (95% CI 16.1 to 16.1)Standard low-calorie diet, earlysame trials9.7Standard low-calorie diet, early: 9.7 percent (95% CI 9.7 to 9.7)Very-low-calorie diet, a year or more latersame trials6.3Very-low-calorie diet, a year or more later: 6.3 percent (95% CI 6.3 to 6.3)Standard low-calorie diet, a year or more latersame trials, gap not significant5Standard low-calorie diet, a year or more later: 5 percent (95% CI 5 to 5)

Medically supervised formula diets under 800 calories a day, which apply to a home soup diet only by analogy. The early gap was significant and the later one was not. Spreads are reported as standard deviations, so none are drawn. Source: card ev-cabw-07 below.

Another meta-analysis paired very-low-energy diets with a behavioral program. People kept off 8.6 lb (3.9 kg) more at 1 year (95% CI 2.4 to 15 lb (1.1 to 6.7 kg)). By 38 to 60 months the difference was 2.9 lb (95% CI -0.44 to 6.4; metric: 1.3 kg, -0.2 to 2.9), no longer significant. Those were structured programs with support, and a week of soup is not one.

Soup eaters in surveys

A meta-analysis of 7 cross-sectional studies with 45,292 people linked eating soup with lower odds of obesity, odds ratio 0.85 (95% CI 0.79 to 0.91). Surveys taken at one moment cannot show that soup causes weight loss. People who eat soup may differ in their diets in other ways, and public commentary reports the work was industry-funded.

Who should be careful

Fast weight loss raises gallstone risk, and how the diet is built changes that risk. In a meta-analysis of 13 randomized trials with 1,836 adults losing weight by dieting or surgery, diets higher in fat cut gallstone formation against low-fat diets, relative risk 0.09 (95% CI 0.01 to 0.61). The interval is wide, the result did not hold up in a sequential analysis, and our card gives no baseline rate, so it cannot be turned into a count of people. We have no measurement of how much fat a cabbage soup diet contains. In the trials of very-low-energy diets with support, one person was taken to hospital with an inflamed gallbladder, against none in the comparison groups.

The NIH advises people taking warfarin or similar blood thinners to keep their vitamin K intake from food steady, because sudden changes can raise or lower the drug's effect. The NIH page does not name cabbage, and we have no citable figure for the vitamin K in cabbage, so how much a cabbage soup diet changes vitamin K intake is not something this page can measure. We have no card on crash diets in pregnancy, in children or with diabetes medicines, and that gap is not a sign of safety.

Not for everyone. If you take warfarin, keep your vitamin K intake steady and tell the person who manages your blood thinner before switching to a diet built on cabbage or other greens. If you have had gallstones, a very fast diet is worth discussing with a doctor first.

What expert bodies say

We found no position from the NHS, the US National Institute of Diabetes and Digestive and Kidney Diseases or the British Dietetic Association on the cabbage soup diet that we could check and put on a card. The only agency text on this page is the NIH advice on vitamin K and warfarin above.

How we searched

Searched: a local copy of PubMed, queried on 6 October 2026 for cabbage, brassica or cruciferous vegetables with weight, obesity or body fat (93 hits, no weight trial of cabbage). A search for the cabbage soup diet, soup diets and fad diets found 13 hits and no study of the cabbage soup diet. Further queries covered soup and weight (56), soup or preloads and intake (300), fruit, vegetables or energy density in weight reviews (129), very-low-calorie diets and gallstones (7) and regain (45), and cohorts of vegetables and weight change (171). We also searched the NIH Office of Dietary Supplements fact sheets, the web for agency advice and newer reviews, and Retraction Watch for every journal source used. None was retracted.

Included: a meta-analysis of energy density, a one-year soup trial and a soup preload trial. Two meta-analyses of fruit and vegetables that disagree, a meta-analysis of soup and obesity in surveys, two meta-analyses of very-low-calorie diets, a meta-analysis of gallstones during weight loss, and one NIH passage, cited below.

Excluded: trials of brassica vegetables that measured blood markers and not weight. A Korean survey of kimchi and obesity, a different product. A 2026 Cochrane review of intermittent fasting and a review of commercial weight-loss programs, neither of which covers soup or cabbage. Blogs and content sites that cite no study.

What we read: abstracts, with each quotation checked against the abstract text. Full text was not available for the one-year soup trial, the survey meta-analysis or the preload trial.

What we could not get: an agency position specific to the cabbage soup diet, and the vitamin K content of cabbage from a citable food database entry.

What would change this answer

What cabbage contains and how cooking changes it is on the cabbage page.

The food behind this question

The same question for other foods (weight loss)

Sources

  1. ev-cabw-01 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 38 studies
    The meta-analysis of 38 included studies demonstrated that lowering ED considerably reduced energy intake - 223 kcal (95% CI: - 259.7, - 186.0) in comparison to the higher ED interventions.
    Who: children and adults in controlled feeding trials, lower energy density (median 1.1 calories/g) vs higher (median 1.5 calories/g)
    Effect: energy intake -223 calories (95% CI -259.7 to -186.0); food weight eaten unchanged
    Certainty: High heterogeneity; mostly single-meal lab studies, so not a weight outcome.
    Eur J Nutr, 2023 · checked 2026-10-06 · we read the abstract
  2. ev-cabw-02 · Randomized controlled trial(s) · randomized controlled trial, 4 arms, 12 months · n = 200
    At 1 year, weight loss in the comparison (8.1+/-1.1 kg) and two-soup (7.2+/-0.9 kg) groups was significantly greater than that in the two-snack group (4.8+/-0.7 kg); weight loss in the one-soup group (6.1+/-1.1 kg) did not differ significantly from other groups.
    Who: overweight and obese women and men on a dietitian-led energy-restricted exchange diet
    Effect: 1-year weight loss: two soups 7.2 +/- 0.9 kg, one soup 6.1 +/- 1.1 kg, two snacks 4.8 +/- 0.7 kg, no special food 8.1 +/- 1.1 kg
    Certainty: Soup did not beat the plain diet group; the benefit is over high-energy snacks, inside an overall calorie plan.
    Obes Res, 2005 · checked 2026-10-06 · we read the abstract
  3. ev-cabw-03 · Randomized controlled trial(s) · randomized crossover trial · n = 60
    When soup was consumed, subjects reduced meal energy intake by 20% (134+/-25 kcal; 561+/-105 kJ).
    Who: normal-weight men and women, lab lunch once a week for 5 weeks, soup preload 15 min before an ad libitum meal
    Effect: meal energy intake -20% (134 +/- 25 calories) with soup vs no soup; broth, chunky or pureed soups did not differ
    Certainty: Single lab meals; body weight not measured.
    Appetite, 2007 · checked 2026-10-06 · we read the abstract
  4. ev-cabw-04 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 7 studies
    The SMD for 7 studies that met all or most criteria was 0.04 (95% CI: -0.10, 0.17) (P = 0.62).
    Who: adults in RCTs of at least 8 weeks promoting or providing fruit and vegetables for weight loss or prevention of gain
    Effect: SMD 0.04 (95% CI -0.10 to 0.17) for 7 studies; SMD -0.16 (-0.78 to 0.46) for 2 studies meeting all criteria
    Certainty: Few eligible trials; vegetables help only if they replace other calories.
    Am J Clin Nutr, 2014 · checked 2026-10-06 · we read the abstract
  5. ev-cabw-05 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 1,026
    The mean change in body weight was -0.54kg (95% CI: -1.05 to -0.04; n=8; I2 for heterogeneity = 73%, p<0.01) less in the ‘high vegetable and fruit’ intake arms than in the ‘low vegetable and fruit intake’ arms.
    Who: participants in RCTs increasing vegetable and fruit intake without advice to remove other foods, mean 14.7 weeks
    Effect: weight change -1.2 lb (95% CI -2.3 to -0.09; metric: -0.54 kg, -1.05 to -0.04), I2 73%; energy intake +368 kJ (-27 to 762), not significant
    Certainty: High heterogeneity; small effect; disagrees in size with the 2014 AJCN meta-analysis.
    BMC Public Health, 2014 · checked 2026-10-06 · we read the abstract
  6. ev-cabw-06 · Observational data · systematic review and meta-analysis of cross-sectional studies · n = 45,292
    The meta-analysis of the studies of which outcome is odds ratio for obesity revealed that soup consumption is significantly related to lower odds ratio of obesity in combined data (n=45292, OR: 0.85, 95% CI: 0.79-0.91, p<0.0001), suggesting that soup consumption was inversely correlated with a risk of obesity.
    Who: adults in 7 cross-sectional studies
    Effect: obesity OR 0.85 (95% CI 0.79 to 0.91)
    Certainty: Cross-sectional only; reverse causation and diet quality confounding possible; industry-funded per public commentary.
    Physiol Behav, 2020 · checked 2026-10-06 · we read the abstract
  7. ev-cabw-07 · Meta-analysis or systematic review · meta-analysis of randomized controlled trials · n = 6 trials
    VLCDs, compared with LCDs, induced significantly greater short-term weight losses (16.1 +/- 1.6% vs. 9.7 +/- 2.4% of initial weight, respectively; p = 0.0001) but similar long-term losses (6.3 +/- 3.2% vs. 5.0 +/- 4.0%, respectively; p > 0.2).
    Who: adults with obesity in randomized comparisons of VLCD (<800 calories/day) vs low-calorie diets, follow-up at least 1 year
    Effect: short term 16.1% vs 9.7% of initial weight (p = 0.0001); long term 6.3% vs 5.0% (p > 0.2)
    Certainty: Medically supervised formula diets, not a home cabbage soup diet; applies to crash diets by analogy only.
    Obesity (Silver Spring), 2006 · checked 2026-10-06 · we read the abstract
  8. ev-cabw-08 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = 1,836
    Diets high in fat content also reduced gallstones, compared with those with low fat content (risk ratio, 0.09; 95% CI, 0.01-0.61).
    Who: adults losing weight by dieting (8 trials) or bariatric surgery (5 trials)
    Effect: higher-fat vs low-fat diet: gallstones RR 0.09 (95% CI 0.01 to 0.61); UDCA RR 0.33 (0.18 to 0.60)
    Certainty: Wide CI for the diet comparison; not confirmed in sequential analysis; no cabbage soup trial.
    Clin Gastroenterol Hepatol, 2014 · checked 2026-10-06 · we read the abstract
  9. ev-cabw-09 · Meta-analysis or systematic review · systematic review and meta-analysis of randomized controlled trials · n = —
    One serious adverse event, hospitalization with cholecystitis, was reported in the VLED group and none in the comparator group.
    Who: overweight adults in RCTs of very-low-energy diets plus behavioral program vs behavioral program alone
    Effect: -8.6 lb (95% CI -15 to -2.4; metric: -3.9 kg, -6.7 to -1.1) at 1 year; -2.9 lb (-6.4 to 0.44; metric: -1.3 kg, -2.9 to 0.2) at 38 to 60 months; 1 serious adverse event (cholecystitis) in VLED arms
    Certainty: Structured programs with support; effect fades by 3 to 5 years.
    Obes Rev, 2016 · checked 2026-10-06 · we read the abstract
  10. ev-cabw-10 · Position of an expert body · agency fact sheet · n = —
    People taking warfarin and similar anticoagulants need to maintain a consistent intake of vitamin K from food and supplements because sudden changes in vitamin K intakes can increase or decrease the anticoagulant effect [45].
    Who: people taking warfarin or similar anticoagulants, NIH Office of Dietary Supplements vitamin K fact sheet
    Effect: sudden changes in vitamin K intake can raise or lower the anticoagulant effect
    Certainty: Cabbage as a vitamin K source is an inference from food composition, not stated on the ODS page.
    NIH Office of Dietary Supplements, Vitamin K fact sheet for health professionals · checked 2026-10-06 · we read the section

How this page was made. Evidence was extracted from primary sources into cards, every number was re-checked against the source, and the text was written from those cards. Bioma Learn has no human medical reviewer at this time, and we say so rather than invent one. Methodology. This is information, not medical advice.

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