Dietary considerations can present a Hobson’s choice in diabetes. Even when the intake is nutritious, assimilating it can be another matter. Then there is the problem of progression of diabetic complications if one ends up with excess glucose or fat in the system. Excess carbohydrates in a meal, and the resulting uncontrolled blood sugar levels can be detrimental to any number of tissues, from the lens of the eye, to the neurons, small blood vessels and the kidneys. Fat is also a problem with increase incidences of atherosclerosis, large vessel disease and cardiac complications. What, then is the appropriate macronutrient for the diabetic population? Enough medical literature exists to suggest that in diabetes, proteins are probably the best bet.
Proteins are the natural choice of the body when faced with diabetes. In uncontrolled diabetes, muscle protein is broken down into amino acids to be converted into glucose by the liver. If left to fend for itself, this can create a commotion within the body. Since proteins have to supply enough energy to substitute for carbohydrates, proteins are broken down faster than they are made. The body ends up with a protein deficit, a situation with subtle, yet far-reaching effects on normal body functions. Importantly, for diabetics, a protein deficit has been shown to impair resistance to infections (Ganong WF). Replenishing the depleting protein stores is a vital requirement of all diabetic diets.
Importance of proteins in a diabetic has been well documented. The American Associations of Clinical Endocrinologists have made it clear that not much evidence exists to indicate that the patients with diabetes need to reduce their intake of dietary proteins. The AACE recommends that 10-20% of the calorie intake in diabetes should come from proteins (AACE Diabetes Guidelines). It is in fact believed that this is one nutrient that does not increase blood glucose levels in both diabetics and healthy subjects (Gannon et al).
Nutrition therapy for diabetes has progressed from prevention of obesity or weight gain to improving insulin’s effectiveness and contributing to improved metabolic control (Franz MJ). In this new role, a high protein diet (30% of total food energy) forms a very pertinent part of nutrition therapy. One of the most important causes for type II diabetes is obesity. Excess body fat raises insulin resistance and higher levels of insulin are required to bring down blood sugars as the weight increases (Ganong WF). Another problem with excess fat is the clogging of arteries with atherosclerotic plaques that is responsible for a wide range of diabetic complications. Any mechanism that reduces body fat decreases insulin resistance and improves blood glucose control. Parker et al have also shown that a high protein diet decreased abdominal and total fat mass in women with type II diabetes. Other studies by Gannon et al. and Nuttall et al have verified that blood glucose levels and glycosylated hemoglobin (a marker of long term diabetic control) reduce after 5 weeks on a diet containing 30% of the total food energy in the form of proteins and low carbohydrate content. It is speculated that a high protein diet has a favorable effect in diabetes due to the ability of proteins and amino acids to stimulate insulin release from the pancreas. Thus, a high protein diet is not only safe in diabetes, but can also be therapeutic, resulting in improved glycemic control, and decreased risk of complications related to diabetes.
The benefits of a high protein diet do not end here. Individual protein components of such a diet, when aptly chosen, can have other advantages as well. Dietary supplements containing proteins like whey and casein come highly recommended. Casein is a milk protein and has the ability to form a gel or clot in the stomach. The ability to form this clot makes it very efficient in nutrient supply. The clot is able to provide a sustained, slow release of amino acids into the blood stream, sometimes lasting for several hours (Boirie et al. 1997). A slow sustained release of nutrients matches well with the limited amount of insulin that can be produced by the pancreas in diabetes. A protein supplement containing casein can thus increase the amount of energy assimilated from every meal and, at the same time, reduce the need for pharmacological interventions to control blood sugar.
Whey proteins and caseins also contain “casokinins” and “lactokinins’, (FitzGerald) which have been found to decrease both systolic and diastolic blood pressure in hypertensive humans (Seppo). In addition, whey protein forms bioactive amine in the gut that promotes immunity. Whey protein contains an ample supply of the amino acid cysteine. Cysteine appears to enhance glutathione levels, which has been shown to have strong antioxidant properties — antioxidants mop up free radicals that induce cell death and play a role in aging.
Thus, development of a protein supplement containing casein and whey can provide an apt high protein diet and its health benefits to individuals suffering from diabetes, obesity and hypercholesterolemia.
