Candida J. Rebello

Whole Grains and Pulses: A Comparison of the Nutritional and Health Benefits

Nutrition plays an important role in the prevention and management of disease. Whole grain cereals contain a host of nutrients and bioactive substances that have health-promoting effects. Epidemiological evidence shows a consistent inverse association between whole grain intake and the risk of chronic disease. Despite a concerted effort by scientists, educators, and policy makers to promote the consumption of whole grains, it remains dismally short of the recommended intakes. Pulses (dried beans and peas) differ from whole grains in their structural and physicochemical properties and have varying amounts of fiber, resistant starch, vitamins, minerals, and other bioactive components; nevertheless, these food groups complement each other. Observational as well as intervention trials show that pulse consumption has beneficial effects on the prevention and management of chronic disease. The nutritional and phytochemical components of pulses coupled with those of whole grains suggest a potential synergistic effect that could provide significant health benefits.

Dietary Strategies to Increase Satiety

Obesity has a multifactorial etiology. Although obesity is widespread and associated with serious health hazards, its effective prevention and treatment have been challenging. Among the currently available treatment approaches, lifestyle modification to induce a negative energy balance holds a particularly larger appeal due to its wider reach and relative safety. However, long-term compliance with dietary modifications to reduce energy intake is not effective for the majority. The role of many individual nutrients, foods, and food groups in inducing satiety has been extensively studied. Based on this evidence, we have developed sample weight-loss meal plans that include multiple satiating foods, which may collectively augment the satiating properties of a meal. Compared to a typical American diet, these meal plans are considerably lower in energy density and probably more satiating. A diet that exploits the satiating properties of multiple foods may help increase long-term dietary compliance and consequentially enhance weight loss.

Functional foods to promote weight loss and satiety.

Purpose of reviewDiets that induce negative energy balance continue to be the cornerstone of obesity management. However, long-term volitional reduction in energy intake is challenging. Functional foods that enhance satiety may have an important practical application in increasing compliance to weight loss diets and thereby promoting sustained weight loss. Here, we present recent advances in identifying common foods that increase satiety. Recent findingsProtein induces satiety in the short term. There is no clear evidence to indicate superiority of a specific protein source over the other. Low-fat dairy products, eggs, and legumes enhance satiety. Although energy dense, nuts have some satiety-inducing effect, when included in the diet by isocaloric replacement of usual foods. Satiety induced by dietary fiber sources, such as oats and rye, are well documented, but these sensations do not always translate into reductions in energy intake or body weight. SummarySeveral foods and food groups show promising potential in inducing satiety. However, it is important to recognize that the short-term effect of a food may not always translate into greater weight loss in the long term. Long-term clinical studies are needed to demonstrate the utility of a food in promoting weight loss.

Instant Oatmeal Increases Satiety and Reduces Energy Intake Compared to a Ready-to-Eat Oat-Based Breakfast Cereal: A Randomized Crossover Trial

Background: Foods that enhance satiety can help consumers to resist environmental cues to eat and help adherence to calorie restriction. The objective of this study was to compare the effect of 2 oat-based breakfast cereals on appetite, satiety, and food intake. Methods: Forty-eight healthy individuals, 18 years of age or older, were enrolled in a randomized, crossover trial. Subjects consumed isocaloric servings of either oatmeal or an oat-based ready-to-eat breakfast cereal (RTEC) in random order at least a week apart. Visual analogue scales measuring appetite and satiety were completed before breakfast and throughout the morning. Lunch was served 4 hours after breakfast. The physicochemical properties of oat soluble fiber (β-glucan) were determined. Appetite and satiety responses were analyzed by area under the curve. Food intake and β-glucan properties were analyzed using t tests. Results: Oatmeal increased fullness (p = 0.001) and reduced hunger (p = 0.005), desire to eat (p = 0.001), and prospective intake (p = 0.006) more than the RTEC. Energy intake at lunch was lower after eating oatmeal compared to the RTEC (p = 0.012). Oatmeal had higher viscosity (p = 0.03), β-glucan content, molecular weight (p < 0.001), and radius of gyration (p < 0.001) than the RTEC. Conclusions: Oatmeal suppresses appetite, increases satiety, and reduces energy intake compared to the RTEC. The physicochemical properties of β-glucan and sufficient hydration of oats are important factors affecting satiety and subsequent energy intake.

Reward-Induced Eating: Therapeutic Approaches to Addressing Food Cravings

The homeostatic controls over eating are inextricably linked to the reward aspects of eating. The result is an integrated response that coordinates the internal milieu with the prevailing environment. Thus, appetite, which reflects a complex interaction among the external environment, behavioral profile, and subjective states as well as the storage and metabolism of energy, has an important role in the regulation of energy balance. In the prevailing food environment which offers an abundance of food choices it is likely that the motivation to consume from a wide range of delectable foods plays a greater role in contributing to overeating than in the past when the motivation to eat was largely governed by metabolic need. The response to food-related cues can promote strong desires to eat known as cravings by activating the mesocorticolimbic dopamine neurocircuitry. Cravings are associated with subsequent eating and weight-related outcomes. Being able to control food cravings is a determinant of success at adhering to an energy-restricted diet regimen. Increased understanding of the neurocircuitry of appetite regulation, especially reward-related eating behavior, has provided potential targets for therapeutic anti-obesity agents specifically directed at reward mechanisms. The naltrexone–bupropion combination and lorcaserin, which are both approved by the US Food and Drug Administration (FDA) for long-term weight management, have shown promise in addressing craving-related eating behavior. Phentermine and liraglutide are approved as monotherapies for weight management. Preliminary research suggests that liraglutide, as well as phentermine alone or in combination with lorcaserin, may be effective in targeting food cravings. Food components such as thylakoid membranes have also been shown to influence food cravings. This review explores the concepts related to appetite and reward-induced eating behavior, as well as the pharmacological options and food-derived components that may be used to address food cravings.

Acute Effects of a Spinach Extract Rich in Thylakoids on Satiety: A Randomized Controlled Crossover Trial

Objective: By retarding fat digestion, thylakoids, the internal photosynthetic membrane system of green plants, promote the release of satiety hormones. This study examined the effect of consuming a single dose of concentrated extract of thylakoids from spinach on satiety, food intake, lipids, and glucose compared to a placebo. Design: Sixty overweight and obese individuals enrolled in a double-blind randomized crossover study consumed the spinach extract or placebo in random order at least a week apart. Blood was drawn for assessments of lipids and glucose before a standard breakfast meal, followed 4 hours later by a 5 g dose of the extract and a standard lunch. Visual analog scales were administered before lunch and at intervals until an ad libitum pizza dinner served 4 hours later. Two hours after lunch a second blood draw was conducted. Mixed models were used to analyze response changes. Results: Compared to placebo, consuming the spinach extract reduced hunger (p < 0.01) and longing for food over 2 hours (p < 0.01) and increased postprandial plasma glucose concentrations (p < 0.01). There were no differences in plasma lipids and energy intake at dinner, but males showed a trend toward decreased energy intake (p = 0.08). Conclusions: At this dose, the spinach extract containing thylakoids increases satiety over a 2-hour period compared to a placebo. Thylakoid consumption may influence gender-specific food cravings.

Effect of Lorcaserin Alone and in Combination with Phentermine on Food Cravings After 12-Week Treatment: A Randomized Substudy: Lorcaserin, Phentermine, and Craving

This study evaluated the effect of lorcaserin 10 mg twice daily (LOR BID), or with phentermine 15 mg once daily (LOR BID + PHEN QD) and 15 mg twice daily (LOR BID + PHEN BID), in conjunction with energy restriction on food cravings.

Timing the discussion of antiobesity medications during obesity treatment.

Current obesity guidelines suggest that sustained weight loss of just 3% to 5% achieved through lifestyle interventions is clinically important (1). A recent randomized clinical trial demonstrated that 5% weight loss in people with obesity increased insulin sensitivity in fat, muscle, and liver while decreasing plasma concentrations of glucose, insulin, triglycerides, alanine transaminase, and leptin (2). Since a lifestyle program emphasizing nutritional changes and increased physical activity is beneficial for people of any weight, such a program has been recommended as the underlying foundation of weight loss interventions. Obesity treatment guidelines state that for individuals with a BMI 30 kg/m or BMI 27 kg/m and at least one obesity-related comorbidity who are motivated to lose weight, pharmacotherapy is an optional addition to lifestyle change efforts (1). However, specific guidelines regarding the time at which antiobesity medications should be added to a program emphasizing lifestyle changes are singularly lacking.

Centrally Acting Agents for Obesity: Past, Present, and Future

For many years, obesity was believed to be a condition of overeating that could be resolved through counseling and short-term drug treatment. Obesity was not recognized as a chronic disease until 1985 by the scientific community, and 2013 by the medical community. Pharmacotherapy for obesity has advanced remarkably since the first class of drugs, amphetamines, were approved for short-term use. Most amphetamines were removed from the obesity market due to adverse events and potential for addiction, and it became apparent that obesity pharmacotherapies were needed that could safely be administered over the long term. This review of central nervous system (CNS) acting anti-obesity drugs evaluates current therapies such as phentermine/topiramate, which act through multiple neurotransmitter pathways to reduce appetite. In the synergistic mechanism of bupropion/naltrexone, naltrexone blocks the feed-back inhibitory circuit of bupropion to give greater weight loss. Lorcaserin, a selective agonist of a serotonin receptor that regulates food intake, and the glucagon-like-peptide-1 (GLP-1) receptor agonist liraglutide are reviewed. Future drugs include tesofensine, a potent triple reuptake inhibitor in Phase III trials for obesity, and semaglutide, an oral GLP-1 analog approved for diabetes and currently in trials for obesity. Another potential new pharmacotherapy, setmelanotide, is a melanocortin-4 receptor agonist, which is still in an early stage of development. As our understanding of the communication between the CNS, gut, adipose tissue, and other organs evolves, it is anticipated that obesity drug development will move toward new centrally acting combinations and then to drugs acting on peripheral target tissues.