Who benefits from apple cider vinegar for blood sugar, and how much should you take?
The strongest evidence for blood sugar benefits comes from people with type 2 diabetes who take ACV consistently. In a 2023 randomized trial, 30 ml (about 2 tablespoons) of ACV per day for 8 weeks produced a statistically significant drop in fasting blood glucose and a significant improvement in HbA1c compared to a control group that followed the same healthy diet [2]. The HbA1c difference between groups was significant (p < 0.001), meaning the vinegar added benefit beyond diet alone. A 2026 study using a slightly lower dose (15-20 ml in water before bed for 6 months) also found significant reductions in both fasting blood sugar (p = 0.012) and HbA1c (p = 0.023) [1]. These results suggest that daily, long-term use—not occasional sips—is what matters.
The dose matters. Both studies used 15-30 ml per day (roughly 1-2 tablespoons), taken with water, typically before a meal or at bedtime. The 2023 study split the dose into two 15 ml servings before lunch and dinner [3], while the 2026 study used a single 15-20 ml dose at night [1]. Starting with a smaller amount (e.g., 1 teaspoon diluted in water) and gradually increasing can help avoid throat irritation or digestive discomfort. Importantly, ACV should always be diluted—undiluted vinegar can damage tooth enamel and the esophagus.
What ACV can and cannot do for blood sugar control
ACV appears to lower fasting blood sugar and HbA1c, but it does not replace standard diabetes treatments. In the 2023 trial, the ACV group also saw improvements in LDL ('bad') cholesterol and total cholesterol, suggesting additional metabolic benefits [2]. The 2026 study noted that ACV helped control an abnormal protein (VEGF165) linked to diabetic eye disease, hinting at possible protective effects on the retina [1]. However, these are early findings, and the studies were relatively small (110 and 70 participants, respectively).
ACV is not a quick fix. The blood sugar reductions, while statistically significant, were modest—not the dramatic drops seen with insulin or some oral medications. For example, in the 2023 study, the fasting glucose decrease was significant only in the ACV group, but the absolute change was not large enough to normalize blood sugar in most participants [2]. Also, ACV does not help everyone equally: the 2026 study noted that only about half of participants (48.2%) strictly took the vinegar daily, and those who did saw the best results [1]. Consistency is key.
There is no evidence that ACV helps with blood sugar in people without diabetes. The studies above all enrolled people with type 2 diabetes. For healthy individuals, the effect on blood sugar is likely negligible.
What the research doesn't tell you—caveats and limitations
The existing studies have important limitations. The 2023 trial lasted only 8 weeks, so long-term effects (beyond 2 months) are unknown [2]. The 2026 study followed patients for 6 months but was conducted specifically in people with diabetic eye disease awaiting cataract surgery, which may not represent the general diabetes population [1]. Both studies were relatively small, and neither was blinded (participants knew they were taking ACV), which can introduce bias.
ACV can interact with medications. It may lower potassium levels and can affect insulin or diuretics. People with kidney disease or gastroparesis (delayed stomach emptying, common in diabetes) should be cautious, as vinegar can worsen these conditions. Always consult a doctor before starting ACV, especially if you take medication for diabetes or other chronic conditions.
Finally, not all ACV products are the same. The studies used liquid vinegar, not pills or gummies. A 2024 observational study using effervescent tablets found modest weight loss but did not measure blood sugar directly [5]. The concentration of acetic acid (the active compound) can vary between brands, so results may differ.
Sources used in this answer
Effects of apple cider vinegar on VEGF165 and glucose level in Diabetic Mellitus type-II patients
In 110 type 2 diabetes patients, 15-20 ml ACV before bed for 6 months significantly reduced fasting blood sugar (p=0.012) and HbA1c (p=0.023), and lowered a protein linked to diabetic eye disease (VEGF165, p<0.002).
The improvement effect of apple cider vinegar as a functional food on anthropometric indices, blood glucose and lipid profile in diabetic patients: a randomized controlled clinical trial
In a randomized trial of 70 type 2 diabetes patients, 30 ml ACV daily for 8 weeks significantly lowered fasting blood glucose (p=0.01) and HbA1c (p<0.001) compared to a control group, and also improved LDL cholesterol and total cholesterol.
Effect of the Apple Cider Vinegar on Weight Management, Blood Glucose Levels and Lipid Profile among Obese/Overweight Adults: A Randomised Control Trial
In 30 obese/overweight adults, 30 ml ACV daily (split before lunch and dinner) for 60 days reduced HbA1c, cholesterol, triglycerides, and BMI, with consistent weight loss over time.
Apple cider vinegar administration on carcass characteristics and meat quality of broiler chickens.
In broiler chickens, ACV (5 ml/L water thrice weekly) improved carcass yield and lowered meat triglycerides, but this animal study does not directly apply to human blood sugar control.
Apple Cider Vinegar Effervescent Tablets on Gut Health, Obesity and User Experience: An Observation
In 45 overweight/obese adults, daily ACV effervescent tablets for 30 days led to modest weight loss (1.46 kg) and waist reduction (1.13 cm), but blood sugar was not measured.