Vinegar helps lower blood glucose in diabetics

by Christine Lambrakis

People suffering from Type 2 diabetes may be able to take advantage of an inexpensive functional food product to help lower their waking blood glucose, reports a study by an ASU researcher in the December issue of Diabetes Care.

The preliminary study found that taking apple cider vinegar at bedtime favorably affects waking blood glucose in Type 2 diabetics and helps reduce glucose levels by up to 6 percent in some of the cases.

ASU nutrition professor Carol Johnston and her colleague Andrea White, a registered dietitian, studied four men and seven women, ages 40-72, of which 73 percent were taking hyperglycemic medications during the study; none were taking insulin.

Before the start of this pilot study, participants' were asked to record their diets and fasting blood glucose for three days. Then participants followed a standardized meal plan for two days. During the two days, each had to ingest water and a 1-ounce piece of cheese, or two tablespoons of apple cider vinegar and 1 ounce of cheese before bedtime. This procedure was repeated so that each participant had both treatments. There was a three- to five-day "washout" period between treatments.

Based on the data, the vinegar treatment was especially effective for the participants with a fasting glucose greater than 130 milligrams per deciliter (mg/dL). Fasting glucose was reduced 6 percent in this group.

"Finding ways to help those with Type 2 diabetes maintain acceptable blood glucose through foods and diet patterns is far more appealing for many to manage their condition," says Johnston, the Department of Nutrition's chair.

Previous studies have shown that taking vinegar at mealtime can lower the mealtime rise in glucose levels as well. According to the researchers, the antiglycemic effect of acetic acid, the active ingredient in vinegar, has been attributed to reduced starch digestion and delayed gastric emptying.

"However, neither of these explains our findings in this study," Johnston says. "Studies by others have shown that acetic acid may possibly alter the glycolysis and gluconeogenic cycle in the liver, which may benefit diabetic individuals with metabolic disturbances, contributing to a pre-breakfast rise in fasting glucose."

Johnston has been studying the benefits of vinegar for three years and has published papers in various journals about her research. This study is the latest in her efforts to look at the use of vinegar as a way to help prevent and control diabetes, but definitely not her last.

"Because the sample size was low and duration of the study was short, we will continue to do more research," Johnston says.

This story first appeared in ASU Insight.

For more information about vinegar and diabetes, see "A spoonful of vinegar helps the sugar go down."