EDITOR's NOTE: Dr. Michelle Cardel, PhD, RD is our resident expert on all important food information that is healthy, smart, and good for your body, mind, stomach and waistline. Dr. MC will share smart food advice with us on a regular basis and looks forward to answering, discussing any food questions you might have.
EDITOR'S NOTE: This is a two year update on the GLOB Master's Diabetes odyssey.
Managing type 2 diabetes through eating habits can seem complicated, confusing and overwhelming. Luckily, the American Diabetes Association is continually reviewing the latest research on which diets are most beneficial to those with type 2 diabetes. Studies reveal that diets such as the Mediterranean diet, DASH diet, and ketogenic diet can help manage diabetes.
The Mediterranean diet, DASH diet, and ketogenic diet are each uniquely able to facilitate weight loss and improve overall health, especially in those living with type 2 diabetes. There is one thing that all three of these diets have in common: The biggest predictor of success is compliance – the need to actually follow the diet. A study of 1,042 men and women with obesity were assigned to a very low energy diet over 26 weeks and assessed for weight loss. Results revealed that high compliance in both genders was associated with considerably greater reduction in body weight. Similarly, a study comparing the effects of four popular weight-loss diets in 160 participants with obesity showed that adherence to the diet, and not the type of diet, was associated with greater weight loss. In other words, it is less about the details of a diet and more about choosing one that you can enjoy and stick to for favorable results long-term.
University of Florida Nutrition Student Monica Foster and I have identified the benefits, drawbacks of these three diets:
The Mediterranean diet replaces salt to flavor foods with herbs and spice and allows room for red wine in moderation. The intake of red meat, which is known for high saturated fat content, is limited. While butter and margarine are rarely consumed in the Mediterranean region, unsaturated fat sources like avocado, nuts and olive oil are frequently consumed. In fact, following the traditional Mediterranean diet enriched with virgin olive oil has been shown to decrease LDL (bad) cholesterol levels. Beyond food, the Mediterranean diet also encourages enjoying meals with family and friends and getting the recommended amounts of exercise – at least 150 minutes of moderate-to-vigorous physical activity per week.
Including a wide variety of foods in all of the major food groups, this is primarily a plant-based diet rich in fruits and vegetables, whole grains, legumes and healthy fats such as olive oil and nuts. However, it also includes fish and other seafood, poultry, and low-fat dairy. You can also consume red meat, but only a few times a month.
• Helps in Managing Type 2 Diabetes: The abundance of plant-based foods as opposed to highly-processed foods in this diet paves the way to reaching weight loss and diabetes goals. A randomized trial of 215 patients recently diagnosed with type 2 diabetes who followed the Mediterranean diet had greater weight loss and better blood sugar than those who followed a low-fat diet.
• Decreases Cancer Risk: The significant amount of fruits and vegetables consumed in this diet may increase cancer-fighting antioxidants, as suggested by a study including over 25,000 participants. Results from this study showed that those with high adherence to the Mediterranean diet had a significantly lower incidence of cancer.
• Decreases Saturated Fat: This diet is not characterized as a low-fat diet, yet many studies have shown that the consumption of healthy fats as in this diet improves heart health. A 2002 study discovered that adopting the Mediterranean diet decreased heart disease in high-risk patients by 35%. This is most likely because these fats do not increase cholesterol the way saturated and trans fats do.
of the Mediterranean Diet
• Lack of Guidance: Contrary to plans like the DASH diet, the Mediterranean diet fails to provide specific amounts to consume. This may be confusing for those who are more likely to adhere to a diet if they know exactly how much they need to eat at each meal. For example, you have to determine what "moderate intake" means, and that can greatly affect weight-loss and diabetic outcomes.
• Cost: Fresh and unprocessed foods can be expensive.
• Low in Calcium & Vitamin D: Including less dairy can mean less calcium and vitamin D than other diets, so more non-dairy foods that are high in these nutrients should be consumed, for example, calcium-rich foods as part of the Mediterranean diet include almonds, kale, and sardines. Eggs and fatty fish such as salmon and mackerel are great sources of vitamin D.
• Time Commitment: Compared to a diet full of highly-processed foods, a diet rich in fresh fruits and vegetables is likely to require more time in the kitchen. One solution to this is to become more organized and use time management skills. It is all about priorities. The most important priority should be your health, and food is critical to health.
Examples of each food type follow:
• Fresh Fruits – Apples, cherries, grapes, melons, peaches, and pears
• Fresh Vegetables – Typically non-starchy types such as artichokes, arugula, avocado, cucumber, eggplant, kale, olives, and tomatoes
• Whole Grains – Barley, buckwheat, breads, couscous, farro, oats, pastas, polenta, and rice
• Legumes – Chickpeas, green beans, kidney beans, lentils, and peas
• Nuts – Almonds, cashews, pine nuts, pistachios, and walnuts
• Fish and other seafood – Fish rich in Omega-3s include albacore tuna, herring, lake trout, mackerel, salmon, and sardines, and shellfish such as clams, mussels, and shrimp
• Low-fat dairy in Moderation – Cheese, goat milk, kefir, and yogurt
• Olive oil
The Dietary Approaches to Stop Hypertension diet was originally developed to lower blood pressure without medication. Since then, many studies have supported this diet as an ideal plan to reduce the risk of developing many diseases including diabetes, some types of cancer, stroke, and heart disease. It is promoted by the United States Department of Agriculture (USDA) as a diet that not only lowers blood pressure and LDL cholesterol levels but also meets the recommended intakes for all essential nutrients. Much like the Mediterranean diet, the DASH diet is filled with plenty of fruits and vegetables, whole grains, nuts, fish, poultry and low-fat dairy products in moderation. Additionally, sodium is restricted in this diet to improve blood pressure.
of the DASH Diet
• Numerous Health Benefits: While this diet is known for its success in reducing cardiovascular disease risk, the Insulin Resistance Atherosclerosis Study of 862 participants revealed that the DASH diet also has the potential to prevent type 2 diabetes – there was an inverse association between adherence to the DASH diet and incidence of type 2 diabetes.
• Research-Based Claims: The benefits of the DASH diet on blood pressure and LDL cholesterol were documented in three NHLBI-funded trials:
• DASH Trial: The DASH diet lowers LDL (bad) cholesterol and blood pressure when compared with a typical American diet alone or a typical American diet with more fruits and vegetables.
• DASH-Sodium: The DASH diet is better at lowering blood pressure than the typical American diet.
• Premier: When paired with exercise, following the DASH diet can yield weight loss and lower blood pressure.
• Structure: Contrary to the Mediterranean diet, the DASH diet includes charts with recommended servings according to daily calorie needs. Plans can be adjusted to any calorie level needed, from 1200 to 2000 to 3100 calories. Examples of foods and notes on their significance as part of a balanced diet are provided as well. This supportive information simplifies healthy eating, which makes it appealing to those who benefit from structure and guidance in their diet plan.
• Backed by Credible Institutions: The DASH diet is promoted by several influential medical organizations including the American Heart Association, the National Heart, Lung, and Blood Institute (NHLBI), The Mayo Clinic, and the 2015 Dietary Guidelines for Americans.
of the DASH Diet
• Tracking Your Intake: Because the diet is tailored to your daily calorie requirements, it is important to keep track of your total calories and how many servings you are consuming from each food group to ensure you are meeting your needs.
• Perceived Lack of Flavor: Low-sodium foods may seem bland when first starting the DASH diet. This is where herbs and spices can make a huge difference in how well a dish is enjoyed.
• Resources Needed: A study comprised of 30 persons from low-income communities revealed that barriers to maintaining the diet included poor availability of recommended foods, low food quality, cost of healthy foods, and issues with following the diet and feeding other family members, and overall mismatch between preferred foods and foods recommended in DASH.
The Ketogenic Diet is characterized by extremely low carbohydrates – usually around ~20-50 grams per day – and increased fat. The idea behind this method is to force the body into ketosis, or the state of using fuel from fat in place of carbohydrates, which is the body's preferred form of energy. It was first introduced in the early 1920s by Dr. Rollin Woodyatt and Dr. Russell Wilder at The Mayo Clinic as a sustainable epilepsy treatment. It was later discovered the diet could also be effective for weight loss. The ketogenic diet has also been shown to reduce glucose levels and improve other factors in type 2 diabetes. A typical macronutrient breakdown of the keto diet is as follows:
• 60-75% of calories from fat
• 15-30% of calories from protein
• 5-10% of calories from carbohydrates
This is quite different from what the 2015 Dietary Guidelines suggest, which is 10-35% of calories from protein, 20-35% of calories from fat, and 45-65% of calories from carbohydrates.17 Common protein sources in the keto diet include meat, poultry, fish and eggs. The diet restricts intake of breads, fruits, grains, legumes, starchy vegetables, and any processed sweets due to high carbohydrate content. Some healthy fat sources are nuts and seeds, avocado, olive oil and fatty fish such as salmon and mackerel.
of the Ketogenic Diet
• Helps Control Appetite: Because fat is one of the most satiating micronutrients, the feeling of being full lasts longer. Additionally, after a low-carb meal, insulin levels will not spike as much. Without a spike in insulin, glucose will not drop below baseline. Simply put, stimulation of a hunger response soon after eating is much less likely to occur. The keto diet is thus a great option for those with type 2 diabetes, considering high blood sugar is a main feature of the disease.
• Improvements in Metabolic Markers: Several studies support the keto diet as a means of improving many metabolic markers important to those with type 2 diabetes. A study of 132 adults with obesity, of which 83% had diabetes or metabolic syndrome, found that those following a low-carbohydrate diet had decreased blood triglycerides and a smaller reduction in HDL (good) cholesterol than those following a conventional diet. Compared with the standard diet recommended by the American Diabetes Association (ADA), a low carb, high fat diet improved HbA1c, diurnal blood glucose stability, and blood lipid profile. This same study also found that a greater reduction in diabetes medication requirements was sustained in the low-carb group.
• Increased Insulin Sensitivity: A high level of insulin circulating in the blood (insulin resistance) has inflammatory effects on the body. However, someone with high insulin sensitivity is less likely to have this effect. In a randomized trial comparing the effects of a very low-carbohydrate and a low-fat diet on several metabolic markers in moderately overweight persons, it was discovered that participants in the very low-carbohydrate group had improved insulin sensitivity.
of the Ketogenic Diet
• Be Prepared to Plan: Because of the strict nature of this diet, staying on track demands organization and careful calculation. You must be disciplined and dedicated when planning your meals, and that includes being aware of the macronutrient ratios in food that you do not make and measure yourself, like from restaurants.
• Beware of Unhealthy Fats: The keto diet requires a high intake of fat, but it is important to limit animal-based fats or highly saturated fats in general. Red meats such as beef and pork are known for high saturated fat content. Other sources include butter, cheese, cream, and coconut and palm kernel oils. Vegetable fats and oils, however, tend to be unsaturated and therefore better for your health. Some examples are avocado, nuts, seeds and olive oil.
• Low in Fiber: Since fiber-rich vegetables are mostly composed of carbohydrates, persons who follow the keto diet will be compromising their intake of dietary fiber. According to The Mayo Clinic, consuming an adequate amount of fiber lowers cholesterol level while helping to control blood sugar level. Thus, this diet may not be as beneficial to those with type 2 diabetes.
• Short-Term Weight Loss Solution: The keto diet is usually only successful short-term regarding weight loss, typically around 12 weeks, before the body reaches a weight loss plateau. This is because a body in "starvation mode" is more likely to retain weight rather than lose it. This was noted in a study of 377 patients who were fed a keto diet for a year and had body weight measurements taken at weeks 4 and 12, and at 12 months. From baseline to week 4 and from week 4 to week 12, a significant reduction in body weight was observed. However, no significant changes were seen after week 12. Despite these results, it is important to note that while weight loss is a side effect of adherence to the keto diet, it is not the main goal in those looking to reverse type 2 diabetes.
UP NEXT: The GLOB's Ayuervedic Health Coach Ms. Chaya-Sharon Heller Discusses an aternative approach to smart diabetes managament in our final two-year diabetes odyssey series report. Check these GLOB links below for more information regarding the current Type 2 Diabetes epidemic:
GLOB Master's 2 year follow-up Dr. Danielle Susanne Nelson, MD, MPH, is a UF/SHANDS Board Certified Family Medicine Doctor. Dr. Nelson's areas of interest include chronic disease management. Dr. Nelson discusses the positive feedback for diabetics resulting from diabetes group therapy meetings
AMY APONICK HAS WRITTEN AN ARTICLE discussing diabetes and the resources available for persons with diabetes.
AMY APONICK EXPLAINS THE ROLE of meaningful blood glucose testing and diabetes self-management.