Low GL for Diabetes Control

A low GL diet is the perfect diet for controlling and treating type 2 diabetes

Low GL diets are the ideal way to control blood sugar levels and have been shown to increase insulinInsulin is a hormone made by the pancreas. It is responsible for making the body’s cells absorb glucose (sugar) from the blood…. sensitivity. Many studies have found that low GL diets are superior to high carbohydrateCarbohydrates are the primary source of energy for the body as they can be broken down into glucose (sugar) more readily than either protein or…, low fatThere are many different types of fats; polyunsaturated, monounsaturated, hydrogenated, saturated and trans fat. The body requires good fats (polyunsaturated and monounsaturated) in order to… diets in controlling and treating type two diabetes.

Study 1

Two groups of overweight or obese people followed either a low GL diet or a low-fat low-calorie diet for two years. After each person had lost ten per cent of their body weight, other measures of their health were taken. Those on the low GL diet had greater improvements in insulin resistance (blood sugar control), triglycerides (fat circulating in the blood), inflammation and blood pressure compared with those on the conventional low-fat, low-calorie diet. The researchers concluded that a reduction in glycemic load may aid in the prevention or treatment of obesity, cardiovascular disease, and diabetes mellitus.

Pereira M. et al., Journal of the American Medical Association, 2004, Vol 292: pp.2482-2490

Study 2

One group of people followed a low GL diet while another group followed a conventional low-fat, low-calorie diet (Canada’s Food Guide to Healthy Eating). Those following the low GL diet, not only lost more weight, they also had greater improvements in HDL cholesterolHDL is short for high density lipoprotein. It is the “good cholesterol” responsible for removing harmful cholesterol from the bloodstream. High HDL levels reduce the…, triglycerides and fasting glucose compared to those on the conventional low-fat, low-cal diet after six months. These health gains were sustained or improved upon after twelve months. The researchers concluded that ‘implementation of a low GL diet is associated with substantial and sustained improvements in abdominal obesity, cholesterol and blood sugar control’.

LaHaye SA et al., Canadian Journal of Cardiology, 2005, Vol 21(6): pp.489-94

Study 3

In a study published in the Lancet in 2004, two groups of mice were fed either a low-GL diet or a high GL diet and their health compared. Besides being leaner, the low-GL group had better blood sugar control, lower blood fats and did not suffer the pancreatic disruption of the high-GL group.

Pawlak D.B. et al, Lancet,2004, vol 364(9436):pp.778-85

Study 4

Researchers at the Harvard School of Public Health monitored the health of 42,000 middle-aged men for six years and found that those who ate a high GL Diet were one and a half times more likely to develop diabetes than those who ate a low GL Diet. This positive association between GL and risk of diabetes was after taking into account other factors such as age, BMI, smoking, physical activity, family history of diabetes, alcohol consumption, cereal fibreFibre is an important part of a balanced diet. There are two type of fibre; soluble and insoluble. Insoluble fibre helps your bowel to pass…, and total energy intake.

Salmeron J. et al., Diabetes Care, 1997, Vol 20(4): pp 545-550

Study 5

In a separate study, researchers at the Harvard School of Public Health also monitored the health of 65,000 middle-aged women for six years and found that those who ate a high GL Diet were also one and a half times more likely to develop diabetes than those who ate a low GL Diet.

Salmeron J et al., Journal of the American Medical Association, 1997, Vol 277(6): pp. 472-7

Study 6

Researchers at Harvard Medical School assessed two groups of obese adolescents who followed either an unlimited low-GL diet or a low calorieCalories are a measure of the amount of energy in food. Knowing how many calories are in the food we eat allows us to balance…, low fat diet. In addition to losing more weight, those on the low-GL diet improved their insulin resistance while those on the conventional low-fat, low-calorie diet worsened theirs. Worsening insulin resistance is associated with obesity, diabetes and cardiovascular disease.

Ebbeling C. et al, Archives of Pediatric and Adolescent Medicine, 2003, Vol 157: pp. 773-779

Study 7

Fifteen volunteers followed a low-GL diet for twelve weeks while fifteen others followed a conventional low-fat, low-calorie diet. Both diets contained identical numbers of calories. The volunteers then switched diets for a further twelve weeks. Fasting insulin concentrations were significantly lower in the low GL group. Lower fasting insulin is associated with decreased risk of obesity, diabetes and heart disease.

Slabber M et al., American Journal of Clinical Nutrition, 1994, Vol 60(1): pp. 48–53

Study 8

A study of 574 adults in Massachusetts between 1994 and 1997, found that higher total carbohydrate intake, percentage of calories from carbohydrate and glycemic index/glycemic load were related to lower levels of beneficial HDL cholesterol and higher blood triglycerideTriglycerides are a type of fat found in the blood – the body uses them for energy. However, high levels of triglycerides can raise the… levels. These results show an unfavourable effect of increased intake of highly processed carbohydrate on fat profile, which may have implications for metabolic syndrome, diabetes and coronary heart disease.

Ma et al. Journal of the American College of Nutrition, 2006, vol.25(2):pp.155-163

Study 9

64 ‘healthy’ obese adults were put on a low GL diet for a year. This diet consisted of 20g carbohydrate and 80-100g proteinProteins are large molecules consisting of chains of amino acids. Proteins are essential nutrients for the human body – they are a building block of… per day. After a year, their fasting blood sugar levels had more than halved. The decrease in blood sugar was seen most drastically in those with the highest sugar levels to begin with, suggesting that a low GL diet is beneficial for type 2 diabetics.

Study 10

A huge study of over 64 000 Chinese women found that those who had a diet high in high GI carbohydrates, in particular rice, had an increased risk of developing type 2 diabetes. The women were followed for 4 and a half years and information on dietary habits and physical activity was collected throughout. Those who ate the most rice had nearly twice as big a risk of developing type 2 diabetes than the low rice-eaters.

Villegas et al. Arch Intern Med. 2007; 167(21):2310-2316

Study 11

This study of 85 059 women found that low carbohydrate diets are better than low-fat diets in preventing diabetes. The study followed the women over 20 years and found that women who ate less carbohydrate and got most of their fat and protein from vegetable sources were at less risk of developing diabetes. This is the equivalent of our low GL diet and is yet more evidence that this is the best choice for preventing diabetes.

Halton T et al. Am J Clin Nutr. 2008 Feb:87(2):339-46

Study 12

A study in Germany of 32 type 2 diabetics found that simply replacing the higher GL sugars and starches in their diet with a low GL alternative improved markers of metabolic control.  Eating foods supplemented with the very low glycaemic sugar replacer isomalt (30g per day) reduced fasting blood glucose and insulin levels as well as reducing insulin resistance and levels of bad LDL cholesterolLDL is short for low density lipoprotein. It is the “bad cholesterol” which collects in the walls of blood vessels, causing blockages. High LDL levels….

Holub I et al. Horm Metab Res. 2009, vol. 41(12): pp. 886-92

Study 13

A meta-analysis of thirteen studies finds that those eating the highest, compared to the lowest GL have a 20 percent increased risk of developing type-2 diabetes. The GL of the diet was more predicitive of risk than the GI.

Dong J et al. British Journal of Nutrition, 2011 Sep 29:1-6

Study 14

A prospective study of 0ver 205,000 people, free of type-2 diabetes, of which 15,027 went on to develop diabetes, confirms that the higher the GL of their diet the greater was their risk of developing type-2 diabetes. Those who both had a high GL diet and a low intake of cereal fibre (such as oats) had a 50% higher risk of type-2 diabetes.

Shilpa N Bhupathiraju Am J Clin Nutr July 2014

Study 15

A study of over 2,000 middle-aged people and found that those in the highest quarter for the GL of their diet, compared to those in the lowest quarter, had 2.5 times the risk for diabetes. This link was true whether or not they were overweight.

He F,Asia Pac J Clin Nutr. 2018

Study 16

This study from Argentina looked at the GL of the diet of 273 obese children and adolescents. A high GL diet predicted a fourfold increase in risk of developing metabolic syndrome, and also a low HDL level.

Cornejo-Monthedoro A. Arch Argent Pediatr. 2017 Aug

 Study 17

This study from Argentina found that in older adults 65 and over the GL of the diet predicted the
risk of developing metabolic syndrome, as well as abdominal obesity, high triglycerides, low HDL, and high blood pressure.

Juanola-Falgarona M. J Am Geriatr Soc. 2015 Oct

Support for Low GL and Diabetes

Supporting nutrition books, cookery books and supplements for the Low GL lifestyle diet can be found on the HOLFORDirect website.