Dietary strategies for management of Type 1 Diabetes – The Paleo Diet
by Rachel Fenske, BS
I am excited to bring you my second post in a special series for YOUglycemia regarding the complex interactions of type 1 diabetes pathophysiology, diet, and exercise.
Today, I will be reviewing what’s been termed the “Paleo” diet, or “cave-man” diet. The anecdotal indications of the benefits of a paleo diet for T1D management are growing. The paleo diet encourages essentially unlimited consumption of fresh vegetables, lean meats, fish and eggs, and more limited consumption of fruits, nuts, and seeds. Most notably, dairy and grains are prohibited. Prior to the very recent development of commercially available “paleo” snack products, like crackers, tortillas, baked goods, etc., all processed foods were also prohibited on the diet. Thus, a type 1 diabetic following this diet would be consuming a diet high in protein and fat, low in simple starches, while not void of carbohydrates entirely as vegetables would provide a variety of complex starches. These dietary conditions would result in less blood glucose spikes and a general reduction in the volume of daily insulin required, meaning the validity of the anecdotal evidence is somewhat substantiated.
The efficacy of low-carbohydrate diets for individuals with T1D has been evaluated briefly, with a consensus from most studies showing an improvement in blood glucose control and lowering of HbA1c. These improvements are extremely dependent on the level of adherence to the diet. Adherence to the diet is very important due to the dramatic reduction in required insulin. Blood glucose management would become extremely difficult if for one day you decided to switch back to a more standard diet that contained a higher carbohydrate load.
Additional considerations for athletes need to be taken into account as carbohydrates are a crucial source of fuel and are limited on the paleo diet. Primary among these considerations are enhanced insulin sensitivity following exercise and the replenishment of carbohydrate stores on a diet which limits carbohydrate intake. Other studies have attempted to evaluate these concerns for athletes on low carbohydrate diets and have found mixed results dependent on type and duration of exercise. Importantly, results also vary based on how the remaining calories are divided among fats and protein. Low carbohydrate diets themselves are inherently higher in fats and/or protein and this can have a large impact on fuel source availability for an athlete. The complexity of high protein and high fat diets elicits a more thorough evaluation and will be the focus of future posts in this series.
Studies focusing specifically on the “paleo diet” began building in the early 2000s, not all that long ago. One of the earliest proponents and foremost researcher of all things Paleo diet is Dr. Loren Cordain. His interest and research have notably culminated in the popular N.Y. Times Best Seller, “The Paleo Diet”, and more recently “The Paleo Diet – Revised” for athletes. He has worked diligently to synthesize and elaborate on the current body of evidence into a comprehendible, but extensive read. His peer-reviewed work encompasses Paleolithic nutrition and fitness, and has recently focused on the role of milk protein in age-related metabolic diseases.
In addition to the work by Dr. Cordain, some of earliest studies investigating the diet are in healthy volunteers, those with impaired glucose metabolism, or those with type 2 diabetes. Unfortunately, more studies have not strayed from these populations. The data emerging from these studies is mixed (reviewed thoroughly here ); in some cases showing improved blood pressure , insulin sensitivity , and HbA1c , while showing no improvement in others . Markers of inflammation and intestinal permeability, which have been discussed previously in the “Science of Diabetes” series, were shown to be no different, in one study of 24 patients with metabolic syndrome .
Although not directly relevant to type 1 diabetics, these studies of healthy subjects are necessary to establish a baseline effect of the diet and studies of individuals with other metabolic conditions are therefore important to developing a breadth of understanding. From this baseline, researchers could then layer-in studies with T1D subjects and note key differences from healthy controls. To further the research, studies which specifically look at metabolic measures and inflammatory markers in type 1 diabetic patients, as well as subjects with other autoimmune conditions, are necessary to provide a more direct implication of paleo diet on T1D glucose control and other outcomes.
Based on the current body of evidence, it cannot be determined if the paleo diet would be an appropriate therapeutic dietary intervention for individuals with T1D. Far more research is warranted to determine the potential influence such an extreme dietary shift would have on blood glucose management for those with T1D and even more work is required to discern if a paleo diet strategy would be appropriate for an athlete with T1D.