Eating For Weight Management
Weight management is complex, especially for those clients who have tried multiple weight loss programs, and may have lost and regained weight many times. There are however simple dietary and lifestyle strategies that you can encourage, which can make losing weight easier to adhere to, and support success in the long run.
Foods that help with weight management
Nutrients in foods don’t just provide sustenance and energy, they can also affect appetite. Appetite is regulated by a range of hormones in the body. Both hunger-suppressing and hunger-stimulating hormones are produced by the hypothalamus in response to signals stimulated by food intake and from long-term energy balance. Gastrointestinal hormones such as cholecystokinin (CCK) and peptide YY are released in response to nutrients in meals, and leptin is released from adipose tissue. 465 The hypothalamus also receives information from the sight, aroma and taste of food, which all impact on energy intake, appetite control and energy expenditure.1
Cycles of weight loss followed by regain may also have long-term effects on hormone levels, explaining the difficulties of achieving long-term weight management. 465-469
Practical Advice: Include protein foods at each meal
Dietary protein is a strong inhibitor of appetite and food intake, and this appears to be a result of influences on hormones such as: CCK, glucagon-like peptide-1 and peptide-YY and reductions in ghrelin. 470,471 Emerging evidence suggests that we may also eat to achieve a certain level of protein intake – the ‘protein leverage hypothesis. 473-475 This suggests that by diluting protein with carbohydrate and fat, we may be driven to overconsume kilojoules in order to consume a certain level of protein, increasing the risk of weight gain.
Practical advice: Include protein food(s) at every meal – legumes, nuts, dairy, eggs, fish, seafood and lean meats are all good sources.
Focus on fibre
There are two main types of fibre, insoluble and soluble, and both types can have positive effects on appetite and food intake. Soluble or viscous fibres such as beta glucan and pectin appear to reduce appetite better in the short term than insoluble fibres. 476,477 Psyllium-enriched meals, for instance, have been shown to reduce insulin, ghrelin and peptide-YY hormones. 477
Practical advice: Foods high in fibre are filling. Encourage high fibre foods, such as wholegrain breads and cereals, fruit, vegetables, legumes, nuts and seeds. Base meals around wholegrains, fruits and vegetables, and encourage legumes and a handful of nuts daily. Soluble fibre can be found in oats (porridge makes an excellent breakfast choice), psyllium, legumes and fruit skins.
Don’t avoid all fats
Fat may contain more kilojoules and have a less satiating effect than protein per se 478, but when found in a wholefood matrix that also contains protein and fibre, some studies have shown a positive effect on appetite hormones such as insulin and CCK. 479,480 Healthy unsaturated fats are important in cholesterol management and reduction of heart disease risk. However, they have also been shown to be an important component of diets for weight-management. Studies indicate that the most effective diets tend not to be low-fat, high-carbohydrate diets, but those more similar to a Mediterranean-style diet; low in saturated fats, but higher in unsaturated fats. 481,482 Healthy fats also make a diet more enjoyable and easier to stick to. 482
Practical advice: Recommend a small amount of healthy fats in each meal – whole food sources may be particularly useful; include some avocado, nuts, seeds, oils such as canola or olive.
Choose quality carbs
Choosing the right carbs is key in designing a healthy weight-management diet. Foods which are rich in carbohydrates can also be good sources of fibre, (see above). But carbs can also be low-, or high-GI. Low-GI diets have been shown to be beneficial for weight and blood glucose control, as well as reducing cardiovascular risk factors. However, their effect on appetite and satiety remains controversial with some studies showing beneficial effects on hormones and others none. 481-486 Low GI carbohydrate foods are digested more slowly. This helps keep blood glucose levels and carbohydrate stores stocked up for a longer period of time, which may reduce hunger and snacking. 487 Including healthy fats in meals also slows digestion and has a GI-lowering effect for the meal.
Practical tip: Encourage low-GI foods at each meal in serving sizes that fit a quarter of a standard dinner plate. High-fibre, low-GI wholegrains are good choices such as wholegrain toast and rolled oats.
Drinking the right stuff
The effects of liquid calories in the form of sweet drinks such as soft drinks, juices and cordials are controversial. Whether liquid calories are less satiating for their kilojoules than solids is still a matter for debate, as are any possible effects of low-calorie sweeteners. 488 However, the volume of fluids will cause stomach distension and have some effect on appetite.
Practical advice: Avoid the extra kilojoules in soft-drinks, fruit juices and cordials. Choose low-kilojoule drinks, such as low-fat milk, tea, vegetables juices. A glass of water before a meal may help fill the stomach and reduce subsequent food intake.
It’s all in the timing
When meals are eaten, how many, and how fast, are factors in weight control.
Overweight people who are ‘late eaters’ (such as those who eat lunch after 3pm) lose less weight, have a slower rate of weight loss, and are more likely to skip breakfast, compared to those who are ‘early eaters’. 489 Plus eating after 8pm may also increase obesity risk. 490
People who skip meals regularly are likely to lose less weight. 491 Those who specifically skip breakfast are more likely to have a higher BMI or increased risk of weight gain. 492 Encourage clients to eat breakfast and avoid skipping meals.
Three meals, two snacks, no supper
It appears successful weight loss maintainers eat around five meal occasions per day — three meals and two snacks. 493-497 In some cases, irregular snacking can lead to weight gain due to greater energy being consumed over the day due to the type of snack eaten — high in fat, salt and sugar. 492,498 Night-time snacking also appears to affect fat metabolism, and so may affect weight. 499 Encourage three meals and two snacks a day; nutrient-rich snacks based on fruits, vegetables, nuts and low fat dairy, rather than processed snacks high in refined carbohydrates, fat, salt and sugar.
Not so fast
Eating more slowly affects hormones, resulting in better appetite control and less hunger. 500 In general, the speed of eating is linked to being overweight. 497 Encourage clients to eat more slowly, and at the table (not in front of the TV), finish a mouthful before re-loading the fork, and to put utensils down in between mouthfuls.
Sleep to lose weight
Sleep is critical when it comes to weight management. Not only does more awake time mean more frequent eating occasions and a greater intake of energy overall, 490,501 but obese people appear to have a lower sleep efficiency and spend more time eating and sleeping during the daytime hours than normal-weight people. 502,503
Evidence also suggests that sufficient sleep promotes weight-loss, 504 and that reduced sleep (less than 6 hours/night) may result in hormonal changes that hinder weight-loss and may affect body composition. 503
Encourage clients to get about eight hours of sleep. 504 Children and adolescents may need more. In addition, advise patients to remove sleep distractions from bedrooms, such as computers, TVs and smartphones. 504
Author: Lisa Yates, Consultant Dietitian Adv APD
Lisa Yates is an Advanced Accredited Practising Dietitian with 16 years experience in nutrition, communications, clinical practice, as well as strategy development and implementation.