Fruh, Sharon M. PhD, FNP-BC; Mulekar, Madhuri S. PhD; Dierking, Jennifer
Obesity is at an all-time high in the United States. More than one-third of U.S. adults (35.7%) and approximately 17% of children (12.5 million) ages 2 to 19 years old are obese.1 Obesity in the adult is defined as a body mass index [BMI] of 30 or greater.1 Nurse practitioners (NPs) are often expected to advise, prescribe, and monitor specific weight-reduction and weight-control diets for these patients.
Many patients have questions about these diets, and those who are adhering to specific diets need individualized monitoring. Many diets are often marketed and promoted without scientific evidence-based guidelines (likely due to the lack of high-quality clinical trials).2,3 Evidence-based data regarding popular diets is limited, as very few are subjected to randomized, controlled clinical trials.
NPs must identify the validity of many different commercial weight-reduction diets by staying current on the effectiveness, safety, and long-term consequences of these diets. Along with diet, the most successful weight-loss programs include exercise and behavior therapy,2 which is crucial to guide and educate patients effectively on weight loss and lifestyle changes.
Incidence of obesity
Obesity rates in the United States differ by gender and ethnicity: for example, in non-Hispanic Black women, the obesity rate is close to 50% compared to the national statistic of 35.7%.4 Over the past decade, the largest increase in obesity has been in children and minorities.5
Obesity is a risk factor for hypertension, hyperlipidemia, heart disease, and pulmonary disease. It increases the risk of fatty liver disease, gallstones, obstructive sleep apnea, arthritis, cancer, reproductive issues, and psychological problems. Due to the increased prevalence of obesity, type 2 diabetes is on the rise with a younger age of onset than ever before.
The obesity epidemic negatively affects all age groups, and if this trend continues, the current generation of young people could be the first generation that will not outlive their parents due to complications of obesity.6 However, this trend is reversible, as obesity is a risk factor that can be modified through weight reduction and diet control.
Open communication with patients
A 2007 survey of more than 1,000 adults conducted by the International Food Information Council identified that 90% of respondents did not know how many calories they needed to consume daily.7 Education regarding daily caloric intake and calorie counts of common foods is necessary. These starting points can open the discussion of weight and weight loss with patients.8
Before detailing any diet recommendations, providers must be willing to discuss the need for weight reduction with patients. Several studies have indicated that healthcare providers are reluctant to advise patients on weight management plans. One study found that patients were more likely to receive weight-loss advice from family and friends than healthcare providers.9 Another study found that NPs often avoid topics such as weight loss in a patient encounter.10 NPs reported concern about offending patients by discussing weight loss, and although NPs reported providing obesity counseling 75% of the time, according to videotaped patient encounters, obesity counseling was offered only 10% of the time.10
Another study found that providers felt their efforts at obesity counseling were ineffective, and they were doubtful of long-term effective weight-loss strategies.11 One study revealed that healthcare providers reported not enjoying working with patients who have weight issues.12 Slow or no progress in weight loss for overweight patients coupled with frequent relapse rates are possible contributors to this reluctance by healthcare providers. It is important to be aware that healthcare providers are reluctant to discuss weight loss and may overestimate the time spent on weight counseling and dietary guidance.10 Patients would greatly benefit from their healthcare providers discussing the topic of weight loss.
Motivational interviewing technique is a direct, patient-centered counseling style that helps individuals work through feelings about their weight, and it enhances a patient's stimulus for change and to follow a prescribed treatment plan. (See Resources.) A review of randomized controlled trials showed that motivational interviewing strategy has a positive impact on weight reduction. Those in the intervention group resulted in significantly reducing more body weight when compared to the control group.13
Clinical screening recommendations
Abdominal fat is only one of the health risk factors of being overweight. Factors such as smoking, drinking, a lack of exercise, along with an unhealthy diet and stress, can lead to health problems and need to be discussed at screening. Each patient should be clinically screened for obesity with a multifactor approach that includes appropriate nutrition, exercise, and behavioral intervention recommendations.14
Three clinical screenings are recommended for all patients: yearly BMI, yearly waist circumference (WC) and/or a waist-hip ratio (WHR), and the calculation of caloric intake required for a patient to achieve goal weight or maintain weight.
BMI. Typically, a patient's height and weight are measured at every provider visit, but BMI is not calculated. However, calculating BMI using height and weight measurements is easy. The National Heart, Lung, and Blood Institute (www.nhlbi.nih.gov/guidelines/obesity/BMI/bmicalc.htm), and iPhone (apps.usa.gov/bmi-app.shtml) have apps available for calculating BMI. Adults with a BMI of 25 or higher are considered at risk for premature death and disability because they are likely to develop cardiovascular disease (CVD), gallbladder disease, hypertension, type 2 diabetes, osteoarthritis, and certain types of cancer, such as colon and breast cancer.2
WC and/or a waist-hip ratio (WHR). Abdominal obesity measured by WC and a WHR is associated with the risk of CVD. A 1.0 cm (0.4 in) increase in WC is associated with a relative risk (RR) of 2% increase in future CVD, and a 0.01 increase in WHR is associated with an RR of 5% increase in CVD.15 The World Health Organization (WHO) reports risks of metabolic complications as16:
* WC greater than 94 cm (37 in) for men and WC greater than 80 cm (31.5 in) for women can lead to an increased risk of metabolic complications.
* WC greater than 102 cm (40.2 in) for men and WC greater than 88 cm (34.6 in) for women can lead to a substantially increased risk of metabolic complications.
* WHR greater than 0.90 for men and WHR greater than 0.85 for women can lead to a substantially increased risk of metabolic complications.
Caloric intake required to achieve goal weight or to maintain weight. The Mayo Clinic website (www.mayoclinic.com/health/calorie-calculator/NU00598) provides many helpful guidelines for weight loss and offers a free online resource for this purpose.
Strategies for healthful eating
Overweight patients often look for a “magic bullet” to help them lose weight quickly and easily; however, healthy lifestyle changes can be an effective means for long-term weight control. Here are some tips for patient counseling on healthy eating habits for weight loss and control.
Know your numbers. Measure patients' height and weight, and then calculate their BMI. Let patients know their BMI and the number of calories they need to eat each day to maintain their weight or to reach their goal weight.
Calories matter. Encourage patients to record their caloric daily intake. Self-monitoring food intake, exercise, and body weight are key to encouraging accountability and self-management.17 Even though patients often underreport their food intake, keeping track is a helpful tool for self-control. A study showed that the more consistently individuals self-monitored food intake and exercise activities, the more weight they lost.18 There are many helpful free online programs as well as free apps for smartphones, such as www.MyFitnessPal.com).
High-caloric food? Just say no. Encourage patients to avoid high-calorie foods, fast foods, and vending machines. They should eat more vegetables and fruit, which are less calorie-dense foods. High-fiber foods also aid in satiety leading to reduced food intake. Suggest patients keep only healthy foods at home and in the workplace.
Exercise is important. Brisk walking is a great form of exercise. Studies have shown that an overall energy expenditure of about 1,000 calories/week has added health benefits.19 It improves weight loss, and body-fat composition.
Water is better. Encourage patients to drink plenty of water and avoid high-calorie drinks. Soft drinks, juice, and coffee drinks are loaded with calories and sugar.
Avoid marketing gimmicks. Encourage patients to eat foods that are in a natural state, such as fresh fruits and vegetables. Caution them about the food industry's trend of “fortifying” highly processed foods, which are then marketed as “nutritious.” This tactic is misleading.20
Develop healthy eating habits. Encourage patients to develop healthy eating habits. Choosing foods that have very little processing is one of the most sensible approaches to long-term weight control. Eating healthy snacks between meals helps curb hunger so that they are not overly hungry at mealtime. Packing fresh foods such as apples, baby carrots, and celery sticks in an insulated cooler bag can curb visits to the vending machine.
Avoiding sugary drinks and high-sugar, high-sodium foods, as well as saturated fats and refined carbohydrates, has many positive benefits.21 Patients should also avoid eating trans fats, which causes an increased risk of diabetes, heart disease, weight gain, certain cancers, and premature aging.
Eating in. On average, Americans consume one-third of their daily caloric intake from restaurants. A survey of consumers of chain restaurants in New York City found that one-third selected meals with more than 1,000 calories.22 Many restaurants will provide calorie counts or will prepare a lighter entrée upon request. Even many fast-food restaurants have calorie count information available for customers.
Family meals. Encourage both single-parent and dual-parent households to eat dinner together as a family each night. Research has shown that middle-school and high-school students eat healthier when they eat meals together as family.23 Eating dinner while not viewing TV also results in healthier food intake because attention is given to the quality of food consumed.24
Make small changes. If a patient is having difficulty reducing intake by 200 calories a day, a better and more successful plan may be to cut 100 calories a day for the first month, and then 200 calories a day during the second month. For some patients, small changes are easier to sustain than drastic ones. The outcome of reducing 100 calories each day is a loss of 10 lb (4.5 kg) in a year; reducing 250 calories each day can mean a loss of 26 lb (11.8 kg) in a year.
Cutting down portion size and increasing exercise can make a substantial difference, reducing further risk of obesity (walking 2,000 steps will be equivalent to 100 calories spent).25 Implementing small changes has been found to be a legitimate means to cut down on weight and prevent further obesity.25
Stick with it. Adherence to a selected diet is an important characteristic and is associated with weight-loss success.26 One study compared three popular diets (Atkins, Zone, and Ornish) and found that weight loss at 12 months was related more to adherence to diet than to any specific diet.27
Healthcare providers need to be aware of current evidence related to commercial diets, including low-glycemic load diets, low-carbohydrate and high-protein diets, low-carbohydrate diets, and low-fat diets. Conflicting nutritional advice from the media often leaves healthcare providers, as well as patients, confused.
The glycemic index is used to measure the effect of carbohydrate consumption on blood glucose. It indicates the amount of increase in the blood glucose level following consumption of 1 g of carbohydrates compared to that of glucose (a baseline with index 100). Many diets are marketed using their glycemic indexes. An evidence-based review showed that the low-glycemic index diets had a weight loss that was significantly greater (2.2 lb [1 kg]) than conventional/traditional weight-loss diets.28 Diets with a low-glycemic index resulted in a significantly lower cholesterol and change in low-density lipoprotein (LDL) cholesterol. None of the studies reported adverse reactions, such as mortality or decreased quality of life, as a result of using low-glycemic index diets.28 This review did not indicate if the patients were on any of the highly publicized diet plans.
Results from another meta-analysis of individual, randomized controlled trials demonstrated consistent benefits of a lower-carbohydrate diet compared to conventional/traditional (calorie counting) diets in terms of weight loss for up to 24 weeks and in terms of reduced WC for up to 12 weeks.29
A large, 10-year dietary assessment study investigated the relationship between low-carbohydrate/high-protein diets with cancer and cardiovascular mortality.30 This study was interesting because it pointed to the possible negative effects of a diet that is very low in carbohydrates.30
A randomized trial evaluated the consequences of a 2-year regimen with a low-carbohydrate or low-fat diet that included a comprehensive lifestyle modification program. The low-carbohydrate group had greater increases in high-density lipoprotein (HDL) cholesterol levels at all points of measurement of the study and a 23% increase in HDL at the 2-year measurement point.31
Some commercial diets require special food and membership costs (see Popular commercial diets). The demands of individualized weight-loss programs have led to the development of weight-loss programs on the Internet. Some patients prefer Internet programs, as they are anonymous and can be accessed 24 hours a day. Weight Watchers, Jenny Craig, Nutrisystem, and eDiets have commercial programs available online. Most include a virtual visit with a dietitian and a diet tailored to each consumer based on the consumer's food preferences and lifestyle. These Internet interventions incorporate record keeping, accountability, and personal feedback in the planning and implementation of weight loss and maintenance.
The Physicians Committee for Responsible Medicine published an official document criticizing the Atkins diet, citing that it poses a serious threat to health.32 The Atkins diet is a high-protein, low-carbohydrate diet. When high amounts of protein are consumed instead of refined carbohydrates, the body's metabolism no longer burns glucose as fuel; instead, it burns its own stored body fat. A study showed higher LDL and HDL levels, and lower triglyceride levels in patients on the Atkins diet when compared to standard/conventional diets.33 After following the diet for 12 months, saturated fat intake remained high, and LDL increased, despite weight loss, which could put these individuals at risk for cardiac events.34 Several studies found that a significant percentage of those who closely adhered to the diet had a nutritional intake that was inadequate in the area of micronutrients.35
Jenny Craig is a restrictive diet that consists of prepackaged foods marketed by the company with several plans available. A study that evaluated weight loss and retention rates for individuals enrolled in the Jenny Craig Platinum Program found that the clients who remained active achieved weight loss.36 Another study that evaluated retention rates and weight loss with the Rewards Program (improved from the Platinum Program) found that weight loss was greater with Rewards compared to Platinum Program. The Rewards program employed motivational interviewing.37
eDiets is a low-calorie diet given through an online virtual dietitian via a fresh-prepared or flash-frozen meal delivery plan; it includes physical fitness and behavior modification to manage stress. A randomized, controlled trial compared eDiets with a group who used a LEARN diet manual for one year. Participants who were assigned to eDiets were provided a 1-year membership, a virtual visit with a dietitian, and prescribed a diet of conventional foods to match their likes and lifestyle. They were given meal plans, grocery lists, and online social support. Those who were assigned to the weight loss manual were given a copy of a weight management book and were encouraged to keep daily records of their food intake. This study found that those following eDiets had minimal weight loss, and it was not as effective as the group using the LEARN diet manual who lost significantly more weight. No significant differences were shown between cardiovascular risk factors or quality of life between the two groups.38
Medifast is a low-carbohydrate, weight-loss meal replacement program that includes prepackaged breakfast, lunch, and dinner plans, with one meal a day prepared independently by the dieter. One research study compared Medifast dieters to food-based dieters. The findings indicated that at 16 weeks, weight loss was significantly greater in the Medifast dieters group compared to the food-based dieters group (12.3% versus 6.9%); however, a significantly greater weight gain occurred in the Medifast dieters compared to food-based dieters on maintenance, and the overall weight loss was greater in Medifast dieters.39
The Mediterranean diet is rich in fiber, omega-3 fatty acids, and antioxidants and includes fruits, vegetables, legumes, nuts, cereal, and whole grains. Olive oil is the main source of fat. Fish and poultry are recommended in moderate amounts, and there is a low consumption of red meat and a moderate amount of wine with meals. A meta-analysis of randomized, controlled studies of the Mediterranean diet found that those who adhered to energy restriction (reduction in calories) on the diet had reduced body fat, when coupled with physical activity with a duration of more than 6 months in length. The diet did not cause weight gain and is associated with a lower risk for CVD and cancer.40,41
Nutrisystem is a diet of home-delivered, portion-controlled, prepackaged meals. A study evaluated weight loss in patients who have type 2 diabetes using Nutrisystem compared to the traditional diabetes support education program. Obese patients with type 2 diabetes who participated in the Nutrisystem diet experienced improvements in glycemic control, weight, and CV risk factors.42
The South Beach diet consists of good carbohydrates and good fats in a three-phase process (eliminate cravings and kick-start weight loss, lose steadily, and maintain for life). A meta-analysis demonstrated that the South Beach Diet equated greater weight loss in patients with diabetes and patients without diabetes at 12 and 24 weeks when compared to energy-restricted, high-carbohydrate diets; however, the difference was small, less than 4.4 lb (2 kg) at 24 weeks. There are no long-term data noted.43
Weight Watchers is a restricted portion and calorie diet available via traditional weekly meetings and online. Two randomized trials found that those who regularly attended Weight Watchers lost approximately 5% of initial weight over 3 to 6 months.44,45 A study that used a primary care referral to Weight Watchers was found to be effective in weight loss. Mean weight change at 12 months was -5.06 kg (SE 0.31) for those in the commercial program versus -2.25 kg (0.21) for those receiving standard care.46
The Zone diet is a carbohydrate-reduced, fiber-rich whole-grains diet based on the idea of reducing cellular inflammation, which, in turn, helps reduce weight. The success of the Zone diet was related to adherence to the diet.26
NPs are on the front lines facing patient questions regarding diet plans. With the increasing obesity epidemic across the country, NPs need to assess and provide dietary guidance to all patients. NPs who are aware of the evidence-based guidelines related to successful strategies and common diet programs are in a better position to provide helpful counsel to patients.
National Lung Heart and Blood Institute, Obesity Education Initiative
“The Practical Guide: Identification, Evaluation and Treatment of Overweight and Obesity in Adults”
United States Department of Agriculture
Alabama Department of Health
“Health Behavior Change: Using Motivational Interviewing”
The Mayo Clinic
“Nutrition and healthy eating”
Popular commercial diets
* High-protein, low-carbohydrate diet. When high amounts of protein are consumed instead of refined carbohydrates, the body's metabolism no longer burns glucose as fuel but burns its own stored body fat.
* Cost varies as prepackaged Atkins food available includes frozen meals, meal replacement bars, snack bars and shakes, treat bars, and breakfast bars and shakes, as well as buying food independently.
* Restrictive diet that consists of prepackaged foods marketed by the company (several available plans).
* $39.99/month plus cost of food for month-to-month option. $19.99/month plus cost of food plus $99 enrollment fee. Cost of food is $14/day to $25/day, or $421.40 to $750 per month.
* Low-calorie diets given through virtual dietitian via a 7-day, fresh-prepared meal delivery program or a 14-day flash frozen program; includes physical fitness and behavior modification to manage stress.
* $199.95 for 1 week (21 meals: 7 breakfasts, lunches, dinners, and snacks) or $28.56 per day
* Low-carbohydrate weight loss meal replacement program includes prepackaged breakfast and lunch plans only.
* $12.13 per day/$363.90 per month, plus cost to prepare 1 meal a day.
* Rich fiber, omega-3 fatty acids, and antioxidants-based diet that includes foods of vegetable origin, fruits, vegetables, legumes, nuts, cereal, and whole grains. Olive oil is the main source of fat. Recommends fish and poultry in moderate amounts, low consumption of red meat, and moderate amount of wine with meals.
* Home delivery of portion-controlled, prepackaged meals.
* $229.99 (includes 28 days of food: breakfast, lunch, dinner, dessert/snack, and protein shake), or $8.21 per day
South Beach Diet
* Good carbohydrates and good fats used in a three-phase diet process (eliminate cravings and kick-start weight loss, lose steadily, and maintain for life).
* Purchase The South Beach Diet Super Charged by Arthur Agatstrom, MD, and buy food independently.
* South Beach foods available: diet bars, gluten-free bars, snack smoothies, protein fit bars, cereal bars, sweet delights. Health and fitness app $1.99 (meal planner, recipes, food and fitness journals, food guide, ask a dietician, weight tracker). For more support, purchase an additional $4.99/week (personalized meal plan).
* Restricted portion and calorie diet available via traditional weekly meetings and online.
* Traditional program is $49/month; standard online program is $48.90 for first month, then $18.95/month.
* Carbohydrate-reduced, fiber-rich, whole-grains diet based on the idea of reducing cellular inflammation, which, in turn, helps reduce weight.
* Purchase The Zone by Dr. Barry Sears. Zone diet food available for purchase: Zone Foods, Zone Nutrition Bars, Shakes, Breakfast Cereal, Protein Powder. $39.95 for 6 boxes of Zone Foods; $35.95 for box of 14 Zone Nutrition Bars. Auto shipping saves 20% on orders.
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