Red wine vinegar: the evidence is about its acetic acid

We found no trial that used red wine vinegar itself, so everything on this page is about the acetic acid all vinegars share. A meta-analysis of 16 randomized trials with 910 adults, about 8 weeks long on average, found fasting glucose 35.7 mg/dL lower (95% CI -63.79 to -7.67) in people with type 2 diabetes. Most of those trials carried an unclear or high risk of bias. The same analysis found triglycerides 20.5 mg/dL lower in overweight but otherwise healthy adults. Five of the 16 trials never stated the dose, and none measured acetate in the blood, so nobody can say how much vinegar the effect needs.

The numbers, per 3.5 oz (100 g)

How much is actually in it

• USDA's only red wine vinegar record lists trace minerals, 0.45 mg iron per 3.5 oz (100 g), and has no measured spread. — USDA SR Legacy record Vinegar, red wine (n = 1 record) Evidence E source
  Iron 0.45 mg (2% DV), copper 0.01 mg, magnesium 4 mg per 3.5 oz (100 g)

What your body absorbs

• In small trials that used about 10 g of vinegar (two teaspoons) with a starchy meal, the glucose rise was 20% lower, while neutralized sodium acetate had no effect, so the acid form matters. — Four crossover trials of 9 to 10 adults each, with and without type 2 diabetes (n = 9-10 per trial) Evidence B source
  Postprandial glucose -20% vs placebo with complex carbohydrate; no effect with monosaccharides or sodium acetate
• Acetate from a vinegar drink reached the blood within 15 minutes in 30 healthy adults, and capsules delivered about 80% as much, peaking at 30 minutes. — 30 healthy subjects, 750 mg acetic acid as capsules or drink (n = 30) Evidence B source
  Drink peak at 15 min, back to baseline at 90 min; capsule peak at 30 min; capsule AUC about 80% of drink, not significantly different

What cooking and storage change

• A salad dressed with vinegar containing 1 g acetic acid lowered the glucose response to a following bread meal by 31.4%, while the same vinegar neutralized to pH 6 did not. — 5 healthy subjects, lettuce with olive oil and vinegar before 50 g carbohydrate as white bread (n = 5) Evidence B source
  Glucose response -31.4% (P = 0.0228) vs neutralized vinegar and blank; gastric emptying unchanged
• Cold-stored boiled potatoes with a vinaigrette of 0.99 oz (28 g) white vinegar had a 43% lower glycemic index than freshly boiled potatoes in 13 healthy adults. — 13 healthy subjects, potato meals with 50 g available carbohydrate (n = 13) Evidence C source
  GI/II 96/128 vs 168/185 for fresh boiled potatoes, -43% and -31%

What it does to your health

• A meta-analysis of 16 RCTs with 910 adults, about 8 weeks on average, found that dietary acetic acid lowered fasting glucose by 35.7 mg/dL in type 2 diabetes against placebo or low-dose comparators. — 910 adults in 16 randomized trials, average 8 weeks, acetic acid from vinegar drinks and foods (n = 910) Evidence A source
  Fasting glucose -35.73 mg/dL (95% CI -63.79 to -7.67) in type 2 diabetes; triglycerides -20.51 mg/dL in overweight adults; no effect on HbA1c or BMI
• In 12 healthy adults, adding 18 to 28 mmol acetic acid as vinegar to white bread lowered blood glucose and insulin at 30 minutes in a dose-dependent way and raised satiety. — 12 healthy volunteers, 50 g available carbohydrate as white bread, 120 min (n = 12) Evidence B source
  Inverse dose-response for glucose and insulin at 30 min; satiety rose linearly with acetic acid

Safety, limits and interactions

• In lab tests on extracted teeth, a 5-minute vinegar exposure raised root dentin permeability, like orange, cola, white wine and lemon juice did. — 25 extracted third molar root segments, 5 per acid (n = 25 specimens) Evidence D source
  All acidic substances increased dentin permeability after scraping (p < 0.05)

What people believe that the data does not support

• The idea of vinegar as a natural appetite suppressant did not hold up: in two studies of 16 and 14 young adults, lower appetite after vinegar came with nausea, and the authors judged it unsuitable for that use. — Healthy, young, normal weight unrestrained eaters, n=16 and n=14 (n = 30) Evidence B source
  Appetite reduced alongside higher nausea ratings; taste alone (sham feeding) had no effect
• Drinking apple cider vinegar daily for a week did not change 24-hour urine citrate, pH or volume, so it showed no sign of preventing kidney stones. — 20 non-stone formers, 6 of whom drank apple cider vinegar for one week (n = 20) Evidence B source
  ACV no significant change; lemon water +167.7 mg/24 h citrate, coconut water +273.8 mg/24 h

Who this works differently for

• In 16 people with type 2 diabetes, vinegar cut the glucose rise after a high-glycemic meal from 311 to 181 mmol min/l but did nothing after a low-glycemic meal. — 16 patients with type 2 diabetes, two matched groups of 8 (n = 16) Evidence B source
  High-GI meal glucose iAUC 181 ± 78 vs 311 ± 124 mmol min/l (P = 0.04); low-GI meal 229 vs 238 (P = 0.56)

What is still unknown

• The vinegar trial base is thin: 5 of 16 RCTs did not state the acetic acid dose, none measured blood acetate, and most carried unclear or high risk of bias. — 16 randomized trials of dietary acetic acid in adults (n = 16 trials) Evidence A source
  Dose unreported in 5 of 16; blood acetate measured in 0; background vinegar intake controlled in 1

The bottom line

Meal tests show the same direction on a smaller scale. In 12 healthy adults eating white bread, more acetic acid meant lower glucose and insulin at 30 minutes. Across small crossover trials of 9 to 10 people, vinegar cut the glucose rise after a starchy meal by 20 percent, and neutralized sodium acetate did nothing. In 16 people with type 2 diabetes, vinegar lowered the glucose curve after a high-glycemic meal from 311 to 181 mmol min/l, with no difference after a low-glycemic meal (P = 0.56). A dressed salad before bread cut the glucose response by 31.4 percent, in just 5 people. Cold boiled potatoes with a vinaigrette scored a glycemic index of 96 against 168 for fresh ones in 13 adults. That arm combined cold storage and vinegar, so the two effects cannot be separated. Two popular ideas failed their tests. In young healthy adults, lower appetite after vinegar came together with nausea, and the authors judged it unsuitable as an appetite suppressant. Apple cider vinegar drunk daily for a week in 6 people did not change urine markers linked to kidney stones. USDA has one legacy record for red wine vinegar, with 0.45 mg iron per 3.5 oz (100 g) and only traces of other minerals. The only safety card is a lab study on 25 extracted tooth roots. A 5-minute vinegar exposure raised dentin permeability, as orange juice, cola, white wine and lemon juice did, with no human outcome measured. The glucose result comes from people with type 2 diabetes, and we have no card on how vinegar adds to glucose-lowering medicine, nor on pregnancy or the stomach. The trials used vinegar with meals in set amounts. This page cannot name an upper amount, and people who take medicine for diabetes should talk to their doctor before adding vinegar to meals regularly.

Sources

1. rwv-r7-12 · USDA FoodData Central SR Legacy, dataset
   Vinegar, red wine (FDC 172240, sr_legacy, Spices and Herbs): iron 0.45 mg = 2% DV; copper 0.01 mg = 1% DV; magnesium 4 mg = 1% DV per 100 g; Foundation samples 0
   USDA FoodData Central, SR Legacy, FDC 172240 · checked 2026-09-28
2. rwv-r7-05 · RCT
   Finally, sodium acetate did not alter PPG, indicating that acetate salts lack antiglycemic properties. ... In these situations, vinegar attenuated PPG by 20% compared to placebo.
   Ann Nutr Metab, 2010 · checked 2026-09-28
3. rwv-r7-06 · RCT
   In the vinegar drink group, serum acetate concentration increased immediately after intake, peaked at 15 min and returned to baseline at 90 min. That in the vinegar capsule group rose slowly, peaked at 30 min and returned to baseline at 120 min.
   J Nutr Sci Vitaminol (Tokyo), 2010 · checked 2026-09-28
4. rwv-r7-07 · RCT
   Similarly, the glucose response was depressed by 31.4% (P = 0.0228) after AcOH+Bread with respect to AcNa + Bread and Blank + Bread.
   Eur J Clin Nutr, 1995 · checked 2026-09-28
5. rwv-r7-08 · Controlled trial
   GI and II of cold potatoes added with vinegar (GI/II=96/128) were significantly reduced by 43 and 31%, respectively, compared with GI/II of freshly boiled potatoes (168/185).
   Eur J Clin Nutr, 2005 · checked 2026-09-28
6. rwv-r7-01 · Meta-analysis of RCTs
   Dietary acetic acid supplementation resulted in significant reductions in TAG concentrations in overweight and obese but otherwise healthy individuals (mean difference [MD] = -20.51 mg/dL [95% confidence intervals = -32.98, -8.04], P = .001) and people with type 2 diabetes (MD = -7.37 mg/dL [-10.15, -4.59], P < .001). Additionally, acetic acid supplementation significantly reduced FBG levels (MD = -35.73 mg/dL [-63.79, -7.67], P = .01) in subjects with type 2 diabetes compared with placebo and low-dose comparators.
   J Acad Nutr Diet, 2021 · checked 2026-09-28
7. rwv-r7-03 · RCT
   A significant dose-response relation was seen at 30 min for blood glucose and serum insulin responses; the higher the acetic acid level, the lower the metabolic responses.
   Eur J Clin Nutr, 2005 · checked 2026-09-28
8. rwv-r7-11 · In vitro
   All acidic substances increased dentin permeability significantly after scraping (p< 0.05).
   Braz Dent J, 2010 · checked 2026-09-28
9. rwv-r7-09 · RCT
   These studies indicate that vinegar ingestion enhances satiety whereas orosensory stimulation alone does not, and that these effects are largely due to poor tolerability following ingestion invoking feelings of nausea. On this basis the promotion of vinegar as a natural appetite suppressant does not seem appropriate.
   Int J Obes (Lond), 2014 · checked 2026-09-28
10. rwv-r7-10 · RCT
    ACV did not significantly change 24-h urinary parameters.
    Int Urol Nephrol, 2026 · checked 2026-09-28
11. rwv-r7-04 · RCT
    In group A, the incremental area under the curve of glucose (GiAUC(120)) was lower after the addition of vinegar (181+/-78 mmol min/l vs 311+/-124 mmol min/l, P=0.04).
    Eur J Clin Nutr, 2010 · checked 2026-09-28
12. rwv-r7-02 · Meta-analysis of RCTs
    Five of the 16 studies did not specify the dose of acetic acid delivered, and no studies measured blood acetate concentrations. Only one study controlled for background acetic acid-rich food consumption during intervention periods. Most studies had an unclear or high risk of bias.
    J Acad Nutr Diet, 2021 · checked 2026-09-28