A review published in Molecular Nutrition and Food Research collates data from human intervention trials showing that vinegar consumption is more effective in modulating glycemic control in “normal glucose-tolerant individuals than in either type 2 diabetics or in those with impaired glucose tolerance.”
A number of factors appear to support the claim that vinegar consumption can improve glycemic control in non-diabetics, including the activation of free fatty acid receptors and increased AMPK functions, thereby leading to a reduction in free fatty acids in circulation and potentially increased insulin sensitivity.
It also appears to increase blood flow to peripheral tissues and increase satiety, leading to lower food intake.
“Asian diets are rich in high-glycemic carbohydrates,” the paper notes. “Asians are also more susceptible to insulin resistance and type 2 diabetes due to increased postprandial glucose and insulin response as compared with other ethnic groups.
“The escalating incidence of type 2 diabetes in Asia has prompted a resurgence of interest in diet-based intervention to manage glucose control. Therefore, the identification of novel functional food based ingredients in Asian diets has emerged as an important areas of research,” states the review, written by researchers at Singapore's Clinical Nutrition Research Centre.
The review states that vinegar is widely consumed across Asia and that its potential as a functional food for improving glycemic control needs to be further explored.
However, the researchers were clear that there is not yet enough evidence to state that vinegar could help those who already had diabetes.
They said that trial data appeared to show that “vinegar supplementation within a normal dietary dosage in healthy volunteers can improve postprandial glycaemia (PPG) and postprandial insulinemia (PPI) when consumed alongside a solid mixed meal. Postprandial insulin also appears to be lower with the addition of vinegar,” they add.
In comparison, the effectiveness of vinegar in reducing PPG and PPI in [people with type-2 diabetes] seemed subdued.
“…the corresponding effects in [type 2 diabetics and impaired glucose tolerance individuals] seem rather weak. Whether chronic consumption of vinegar can benefit long term glycemic control in [diabetics] remains to be determined since the evidence has thus far been equivocal,” they state.
They call for more studies to assess the impact of vinegar on people with diabetes and conclude that given the extensive use of vinegar in Asia “it appears to be a promising functional food to improve glycemic control” among non-diabetics.
Source: Molecular Nutrition and Food Research
2016, 60, 1837-1849. Doi 10.1002/mnfr.201600121
“Vinegar as a functional ingredient to improve postprandial glycemic control – human intervention findings and molecular mechanisms”
Authors: Sumanto Halder, et al