5 evidence based dietary advice for patients

Separating the Wheat From the Chaff: 5 Evidence-Based Dietary Tips to Share With Your Patients

Naveed Saleh, MD, MS

August 09, 2018

Counseling patients on healthy dietary patterns is challenging. So much information abounds that it can be hard to separate the wheat from the chaff.

According to Isabel Maples, MEd, RDN, a spokesperson for the Academy of Nutrition and Dietetics, initial diet advice should focus on encouraging patients to add missing components—most commonly fruits, vegetables, whole grains, and dairy—rather than restriction.

“When people are resistant to change and they don’t want to give up their favorite foods, but they’re scared because they have heart disease or diabetes, I start by focusing on what they can add to their diet instead of what they should subtract, to help them feel successful,” says Maples.

Here are five evidence-based tips to share with your patients.

1. Get the right nutrients. Patients should aim to fulfill their recommended calorie intake with a variety of nutrient-dense foods that span all food groups to boost long-term health. Healthy eating styles may vary from individual to individual and frequently reflect cultural and personal preferences.[1]

In a 2017 study by Micha and colleagues,[2] nearly one half of all cardiometabolic deaths (ie, deaths from heart disease, stroke, and type 2 diabetes) among adults in the United States were found to be associated with suboptimal intake of vegetables, fruits, nuts, seeds, and omega-3 fatty acids.

The US Department of Agriculture (USDA) replaced its food pyramids of yore with MyPlate in 2011.[3] MyPlate illustrates the concepts of balance and portion size that are evident at a glance. The plate is divided into four, roughly equal parts—fruits, vegetable, grains, and proteins—as a simple reminder of how to eat healthier. Lying beside the plate is the fifth food group, dairy, positioned as a beverage. Dairy can be a glass of milk, cheese, or yogurt, or can be substituted with a fortified soy-based beverage.

Advice from the USDA focuses on discovering the individual’s own healthy eating style, which entails the following:

  • Fill half the plate with a variety of fruits and vegetables;
  • Ensure that half of grains consumed are whole grains;
  • Shift to low-fat and fat-free dairy products; and
  • Regularly switch proteins to include such choices as seafood, lean meats and poultry, eggs, nuts, legumes, and seeds.

Vegetables should be consumed in a variety of colors and consistencies, such as dark green, red, orange, leafy, and starchy.

Finally, dairy is important for more reasons than just calcium. “When you eat dairy, you get vitamin D, magnesium, and potassium,” says Maples. “One of the reasons MyPlate increased dairy to three servings from two was to get more potassium in the diet.”

2. Cook meals at home (from scratch, if possible). Processed foods and beverages—including packaged snacks, smoked meats, white flour, and sugar-sweetened items—should be eaten only occasionally.

More specifically, the USDA has quantified limits[4] that may help patients understand exactly how much added sugars, saturated fats, and sodium is healthy: Less than 10% of calories should come from added sugar, less than 10% of calories should come from saturated fats, and less than 2300 mg of sodium should be eaten per day. The average American consumes about 50% more sodium than is recommended, which can raise blood pressure and increase the risk for stroke and heart disease.[5]

Mixed dishes (ie, dishes comprising more than one food group) account for 44% of the average American’s sodium intake.[6] Furthermore, most sodium is consumed in the form of processed or prepared foods and restaurant foods. The remaining salt that people eat comes from snacks, protein foods, grain-based foods, condiments, gravy, salad dressings, and dairy. Contrary to what some may think, the salt shaker is not a substantial source of sodium.

Ultimately, to decrease consumption of added sugars, saturated fats, and sodium, preparing foods at home is key, with premade sauces, mixes, and instant products (ie, instant noodles) used sparingly.[6] Choosing fresh or frozen meats, fish, and poultry instead of processed animal foods is ideal. Fresh or frozen vegetables (without sauce or salt) are healthier than canned foods. Instead of reaching for the salt shaker, consider seasoning vegetables with herbs and spices.

3. For weight loss, choose realistic, balanced diets. The most successful diet is one that patients can stick to. Plenty of diets have proven effective for weight loss and weight maintenance. When dieters fail, it is because they attempt to follow diets that are too restrictive, are unbalanced, or cause rapid weight loss, which leads to yo-yo dieting.

Diets that promote weight loss and weight maintenance include increased consumption of vegetables, fruits, and high-fiber and whole-grain foods; increased intake of water; and reduced consumption of dietary sugar and sugar-sweetened beverages[7]

Low-carb, high-protein diets result in greater weight loss over a given period compared with calorically equivalent diets that contain relatively more carbohydrates.[7] Furthermore, high-protein diets are linked to better long-term benefits with regard to waist circumference, body fat composition, reduced loss of muscle mass, improved cardiometabolic risk factors, and decreased diameter of adipocytes. However, moderate-carbohydrate, moderate-protein diets have also been linked to improved body composition, lipid profiles, and postprandial insulin response.

Specific diets that have proven effective at weight loss plus reduction in body mass index include the DASH (Dietary Approaches to Stop Hypertension) diet, Mediterranean diet, Nutrisystem®, Weight Watchers®, and Jenny Craig®.[7]

The Mediterranean diet is heavy in vegetables; fruits; nuts; whole grains; and healthy unsaturated fats found in olive, avocado, and other plant oils. It focuses more on fish and poultry, and less on lean red meat and dairy. The Mediterranean diet has been correlated with lower risks for cardiovascular disease, cancers, type 2 diabetes, Parkinson disease, and death. Of note, part of the benefit of the Mediterranean diet may be biopsychosocial, with family-style eating, genetics, and active lifestyles all playing a role.[6]

The DASH diet[8] focuses on meeting daily and weekly nutritional goals, and is convenient because no special foods are required. It works well for vegetarians and people who require gluten- or allergen-free foods. Overall, the DASH diet promotes general healthy eating that includes vegetables, fruits, whole grains, fish, poultry, beans, nuts, vegetable oils, and no- or low-fat dairy products. Sugar-sweetened foods and beverages and saturated fats (eg, tropical oils, such as coconut, palm kernel, and palm oils) should be limited.[6] Oft-cited research suggests that 6 months on the DASH diet plus counseling results in significantly lower levels of hypertension in addition to weight loss.[9]

Finally, intermittent fasting has been gaining popularity. Recent research has shown that 12 weeks of time-restricted feeding, a form of intermittent fasting in which an obese person has 8 hours of unrestricted eating followed by 16 hours of water fasting, results in mild calorie restriction and may help with weight loss and blood pressure.[10] Although it’s not for every patient, this type of diet may appeal to some.

4. Choose fats wisely. Fats imbue food with flavor and allow for creamy, moist, or tender consistencies. However, fat calories are more concentrated than those of proteins and carbohydrates, and accumulate quickly.

Instead of giving up fats, the Academy of Nutrition and Dietetics says to “spend your fat calories wisely.”[6] This means substituting with healthier fats to reduce the intake of saturated and trans fats. When cooking, liquid oils can be used instead of solid fats (eg, butter, shortening, or lard). Liquid oils can be polyunsaturated (eg, corn, sunflower, and soybean) or monounsaturated (eg, olive, peanut, safflower, sesame, and canola). Oils also add key nutrients, such as vitamin E. Another healthy substitution involves swapping out whole-milk products with low-fat or fat-free milk, cheese, or yogurt.

Emerging research suggests benefits of some saturated fats, including those found in dairy and coconuts. However, until their effects are better elucidated, it is recommended that people continue to limit saturated fats.

Canola oil, which is rich in monounsaturated fat and omega-3 fatty acids, is a subject of controversy. A widespread misconception is that canola oil contains erucic acid, which has been linked to cancer in animals. In the 1970s, however, canola plants were selectively bred from rapeseed plants to be virtually devoid of erucic acid.[6]

5. Eat plenty of fiber. Prebiotics are beneficial and an integral part of a healthy diet, and dietary fiber is the best known prebiotic.

Prebiotics are selectively fermented ingredients that balance the composition and activity of the gut flora to benefit health.[11] Consumption of dietary fiber is linked to improved cardiovascular health and lower body weight. Furthermore, when used judiciously, fiber laxatives can help with issues of gastrointestinal motility.

Fiber is found in fruits, vegetables, legumes, nuts, and whole and fiber-enriched grains.

“Fiber keeps digestion moving, binds cholesterol, and pushes out carcinogens. It helps you feel full longer and feeds the healthy bacteria in the gut,” says Maples.

Progress, not Perfection

In recent years, diet experts have focused on shifting patient perceptions regarding food. Instead of drastic changes, gradual changes may suffice. Moreover, it is beyond the scope of a single clinical visit to present all available dietary advice.

“It’s okay to tackle one change at a time,” says Maples. “Focus on making progress, not being perfect. Once you’re successful with one goal, pick another goal. Nutrition is about what you’re going to eat for the rest of your life. It’s okay to make small, manageable tweaks rather than a major overhaul.”


  1. US Department of Agriculture. Dietary guidelines for Americans 2015-2020. June 11, 2018. Source Accessed July 31, 2018.
  2. Micha R, Peñalvo JL, Cudhea F, Imamura F, Rehm CD, Mozaffarian D. Association between dietary factors and mortality from heart disease, stroke, and type 2 diabetes in the United States. JAMA. 2017;317:912-924. Abstract
  3. US Department of Agriculture. A brief history of USDA food guides. Source Updated May 11, 2017. Accessed July 31, 2018.
  4. US Department of Agriculture. 2015-2020 dietary guidelines: answers to your questions. January 7, 2016. Source Accessed July 31, 2018.
  5. US Food and Drug Administration. Sodium reduction. February 8, 2018. Source. Accessed July 31, 2018.
  6. Duyff RL. Academy of Nutrition and Dietetics Complete Food & Nutrition Guide. 5th ed. New York, NY: Houghton Mifflin Harcourt; 2017.
  7. Diets for weight loss. DynaMed Plus. EBSCO Information Services. April 13, 2018. Source Accessed July 31, 2018.
  8. National Heart, Lung, and Blood Institute. DASH eating plan. Source Accessed July 31, 2018.
  9. Appel LJ, Champagne CM, Harsha DW, et al; Writing Group of the PREMIER Collaborative Research Group. Effects of comprehensive lifestyle modification on blood pressure control: main results of the PREMIER clinical trial. JAMA. 2003;289:2083-2093. Abstract
  10. Gabel K, Hoddy KK, Haggerty N, et al. Effects of 8-hour time restricted feeding on body weight and metabolic disease risk factors in obese adults: a pilot study. Nutr Healthy Aging. 2018;4:345-353.
  11. Slavin J. Fiber and prebiotics: mechanisms and health benefits. Nutrients. 2013;5:1417-1435. Abstract