Pectin Improves Glycemic Control In Diabetic Patients

A jar of marmaladePectin is a substance found in the cell walls of land-based plants. Pectin combines with water to produce a thick, gel like substance, making it useful as a setting agent in jams and marmalades. Pectin has gained some popularity as a health food due to its ability to lower cholesterol levels. Interestingly, pectin has also shown promise as a potential aid to diabetics as several scientific studies have found improvements in glucose control following pectin supplementation.

An American study, published in The American Journal of Clinical Nutrition in 1988, involved supplementing the diets of 12 type-2 diabetics with 20g per day of apple pectin. The researchers found that pectin supplementation improved glucose tolerance, as measured by 3 hour incremental glucose changes following a test meal, by 19.8%.

A 1977 study, published in the Annals of Internal Medicine by researchers at the Medical Research Council Gastroenterology Unit in London, England, looked at the effects of pectin and guar gum (another soluble fibre) on post-meal glucose levels in 4 healthy volunteers. The researchers found that both substances resulted in significant reductions in glucose levels. The average glucose levels of the 4 participants, 15 minutes after a control meal, was 6.18mmol/L while 10g of pectin added to the same meal resulted in average glucose levels 15 minutes after the meal of 5.64mmol/L, a reduction of 8.7%.

In 2010 the European Food Safety Authority (EFSA), after reviewing the scientific literature, approved the health claim that “Consumption of pectins contributes to the reduction of the blood glucose rise after meals”. The claim applies to products that contain at least 10g of pectin.

The positive effects of pectin on post-meal glucose levels are due primarily to its ability to reduce gastric emptying rates which in turn slows down the release of glucose into the blood-stream. Pectin also appears to increase the thickness of the mucosal layer of the intestines, directly reducing the intestinal absorption of glucose.

Pectin is relatively inexpensive to buy, with good quality powdered fruit pectins typically retailing for $10 to $20 per pound at various health food shops and jam-making supply stores. An alternative to straight powdered pectin is a low sugar marmalade, as these usually contain a significant percentage of pectin (low sugar marmalades require additional pectin to aid setting). Other significant dietary sources of pectin include apples, apricots, peaches, oranges, carrots, beans, and grapefruit. Citrus peels have the highest pectin levels with 25-30% pectin by weight.

Individuals looking to improve their glycemic control through pectin supplementation should begin by taking 5g of pectin (approx 1 tsp) at meal times. If post-meal glucose levels aren’t significantly reduced, this can be increased to 10-15g. Care should be taken not to take excessive amounts of pectin because large amounts of soluble fibre may cause bowel obstruction in some people. In general, as long as pectin supplementation is kept below 30g per day, side effects are unlikely.