"Diet, diet, diet! What is the best diet for me?" While book stands, celebrities and Dr. Google provide numerous options, here is some evidence based information on a few popular diets. Knowledge is power, so become informed!
DASH Diet
What
Dietary Approaches to Stop Hypertension (DASH) was first published in the New England Journal of Medicine in 1997. This diet showed outcomes indicating the use of food as medicine to improve blood pressure, not only in those with hypertension(>140 mmHg/90 mmHg), but also in people with normal blood pressure (120/80). The original study was conducted in 1997 and funded by NHLBI.
What stands out: It is a step ahead in identifying the benefits of minerals and electrolytes in food, with an emphasis on including foods rich in potassium, magnesium, calcium as well as macronutrients heart healthy fats while limiting saturated and trans fats, and promoting high biological value protein and dietary fiber.
Recommended by
National Heart, Lung and Blood Institute (NHLBI), American Diabetes Association (ADA) and American Heart Association(AHA)
Evidence Based Outcomes for
Weight Management - Minimal weight changes with the DASH diet itself, improved outcome when other lifestyle factors such as physical activity and sleep were recommended. Depending on the caloric restriction assigned during the study, participants lost 2.8%-8% of their baseline body weight.
Diabetes - In a systematic review of studies on the Dietary Patterns and Cardiovascular Disease Risk in People with Type 2 Diabetes, the DASH diet significantly improved insulin sensitivity and showed a reduction in HgbA1C of -0.53%. The SEARCH for diabetes in youth study(youths with type 1 and type 2 diabetes), indicated that an increased adherence to a DASH-like diet, significantly reduced the risk of cardiovascular diseases.
Heart Health - Alongside the Mediterranean diet, it has been ranked over consecutive years by the American Heart Association as most beneficial for Heart Health.
Sustainability and Public Interest
The diet was studied over a period of 11 weeks. Adherence to DASH on a national level continues to be poor. A decade-old analysis of data from the National Health and Nutrition Examination Survey (NHANES) showed that less than 1% of the US population was fully adherent to DASH in 1988 to 2004, and only 20% met half of the recommended levels of nutrients in DASH. Analyses using more recent NHANES data from 2007 to 2012 showed similarly poor adherence
Reason: Energy-dense, nutrient-deficient foods are highly accessible in the US and inexpensive. Fruits and vegetables tend to be more expensive than other foods that can be purchased at fast-food restaurants. This is particularly true for low-income individuals where access can be an issue.
Goal: Vital to identify barriers and individualize the meal to reduce environmental, cultural, financial and preferential concerns. Adaptation of the DASH diet have been studied.
Based on a review completed 20 years later a way to promote the DASH diet is to include innovative strategies to induce sustainable behavior change. A focused strategy to improve patient self-management is the use of digital health tools and having registered dietitians and health coaches on a care team.
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Mediterranean Diet
What
The Mediterranean diet evolved from the eating habits of countries bordering the Mediterranean sea. Thus the name. A growing body of scientific evidence shows that the Mediterranean Diet has a beneficial effect on obesity, metabolic syndrome, cardiovascular disease, and diabetes. Primarily a plant based meal plan, rich in nuts, seeds, olive oil, legumes and whole grains, fruits and vegetables, with room for dark chocolate and wine. Other foods like animal proteins are eaten in smaller quantities, with the preferred animal protein being fish and seafood.
What stands out: It continues to receive the tag of ‘overall best diet’ per the U.S News and World Report, for four consecutive years. It also allows for plenty of room to personalize a meal plan, making it a practical option for many. The focus is less on restriction of nutrients, and more on inclusion of heart healthy foods.
Recommended by
AHA, ADA
Evidence Based Outcomes for
Weight Management - One review of 5 studies found that the Mediterranean diet was as effective as other popular diets like the low carb diet or low fat diet for weight loss, resulting in up to 22 pounds (10 kg) of weight loss over 1 year
Diabetes - A review of dietary patterns and cardiovascular risk in people with type 2 diabetes, showed the mediterranean way of eating, improved HbA1C, LDL, as well as reduced diabetes related complications. A 42% relative risk reduction in diabetic retinopathy was noted. This reduced risk in microvascular complications was primarily associated with adequate intake of extra virgin olive oil, nuts and sofrito.
In the PREDIMED study, a longitudinal study done over a period of 4 years also indicated a 52% reduction in the incidence of type 2 diabetes.
Heart Health - A study of nearly 26,000 women found that those who followed this type of diet had 25% less risk of developing cardiovascular disease over the course of 12 years. The PREDIMED study, a primary prevention trial including thousands of people with diabetes or other risk factors for heart disease found this diet reduced the rates of death from stroke by roughly 30%. While the study itself was retracted and republished, the outcome of the study in reducing the risk of CVD in people with chronic conditions remained unchanged.
Sustainability and Public Interest
One of the longest dietary interventions studied till date over a period of >5 years. Indicative of the potential with sustaining a dietary pattern. The diet has evolved to meet needs based on culture as well as different socioeconomic background. Its focus on inclusion of nutrients, especially with an emphasis on heart healthy fats and whole grains makes this meal plan a popular plan to the consumer’s eye.
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Ketogenic Diet
What
The ketogenic diet is a very low carbohydrate(5-10% of kcals), high fat (70-80% of kcals) and moderate protein diet(10-20% kcals). Originally recommended in the 1920s in the treatment of children with epilepsy, it has gained popularity as a weight loss diet as well as for people with diabetes. The intent is to induce nutritional ketosis by using up glycogen stores, to promote ketone production and burn fat to lose weight and improve insulin sensitivity.
Recommended by
Thus far no governing bodies have recommended this diet plan. While many people do choose to try it for a short duration, it is highly advisable that it be done under medical supervision for people with diabetes.
Evidence Based Outcomes for
Weight Management - Short term benefits to aid with weight loss have been successfully studied up to a period of 12 weeks. In cases where initiating weight loss is a concern, a recommendation to initiate a Ketogenic meal plan under medical supervision, with reintroduction to a more sustainable meal plan can be considered.
Diabetes - In 2008, researchers conducted a 24-week study to determine the effects of a low-carbohydrate diet on people with type 2 diabetes and obesity. At the end of the study, participants who followed the ketogenic diet saw greater improvements in glycemic control and medication reduction compared to those who followed a low-glycemic diet.
Heart Health - While there is no fixed type of fats recommended to achieve the high fat content that the keto diet demands, it is wise to choose most of the fats from heart healthy fats versus the false belief of eating higher amounts of saturated fats. In the absence of approved guidelines, depending on your source of information, ketogenic food lists may vary and even conflict.
Sustainability and Public Interest
Most studies have been short term(1 year) due to difficulty with adherence with this diet.
Comparison studies have indicated that in the longer duration weight loss, A1C change have shown no significant difference between following a ketogenic diet versus a less restrictive meal plan such as a mediterranean or DASH diet. The perks of the short term success seen both in weight loss as well as improvements in glycemic control have made this diet a popular choice to consider. Medical supervision is highly recommended for patients considering to follow this diet.
Some negative side effects of a long-term ketogenic diet have been suggested, such as increased risk of kidney stones and osteoporosis, and increased blood levels of uric acid.
This diet is NOT recommended for people with renal or liver disorders, or people with eating disorders.
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Plant Based Diet
What
Plant-based or plant-forward eating patterns focus on a vegetarian meal plan. Besides the obvious fruits and vegetables, it also includes and emphasizes the use of nuts, seeds, oils, whole grains, legumes, and beans in the meal plan. It does not necessarily mean that one can never eat meat or dairy. Rather, one can proportionately choose more of the foods from plant sources. The mediterranean diet does emphasize a similar way of eating.
Plant based diets are loosely described, as seen in this table, thus challenging to identify a particular type of a primarily plant based diet and its effect on weight, blood glucose and heart health. By and large all focus on either omitting all animal products (vegan diets) or choosing animal based proteins less often.
Recommended by
Dietary Guidelines Advisory Committee, Physicians Committee for Responsible Medicine, ADA and AHA recommend a ‘primarily’ plant based meal plan.
Evidence Based Outcomes for
Weight Management - In a systematic review of 22 publications, most of which were randomized controlled trials. the duration of intervention ranged between 10 weeks to 12 months, 5 of which had a follow-up period between 5 and 24 months. Majority of the studies did show weight loss with dietary interventions in the plant based groups(both vegetarian and vegan groups) as compared to those on an omnivorous diet. More importantly, the findings in the EPIC-Oxford study, showed that during 5 years of follow up, those following a vegan and vegetarian diet showed overall a smaller weight gain than meat-eaters.
Diabetes - Evidence from clinical trials has shown that vegetarian diets reduce A1c levels, suggesting that they may be beneficial in the prevention and management of type 2 diabetes. In July 2019, in a meta analysis of studies published in the Journal of the American Medical Association, those with a higher adherence to a plant based diet had a 23% lower risk of developing type 2 diabetes. Of importance to note is that the studies kept in mind those following a healthy plant based diet as compared to those with less healthful plant based choices.
Heart Health - A study published in the Journal of the American College of Cardiology found that people who followed the healthy plant-based diet had the lowest risk for heart disease. They were also more active and leaner. On the other hand, those who followed the unhealthful plant-based diet had a substantially higher risk for heart disease.
Sustainability and Public Interest
Documentaries such as The Game Changer as well as increased awareness of the role of dietary fiber and healthy fats on heart health has kept the interest high in the public’s eye to include plant based meals, but not as much towards a complete switch to a vegan or vegetarian meal plan. Education is still key in guiding people towards identifying healthy plant based options as well as flexible options that support one's cultural and socioeconomic needs.
Reference
A Clinical Trial of the Effects of Dietary Patterns on Blood Pressure
Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet
Plant-Based Eating Pattern for Type 2 Diabetes Prevention and Treatment
Association Between Plant-Based Dietary Patterns and Risk of Type 2 Diabetes
Dietary Patterns and Cardiovascular Disease Risk in People with Type 2 Diabetes
An Update on the Mediterranean, Vegetarian, and DASH Eating Patterns in People With Type 2 Diabetes