There are many benefits to losing weight, and the loss does not have to be substantial. A modest 5-10% weight loss can improve chronic disease risk factors such as dyslipidemia (by lowering LDL cholesterol, raising HDL cholesterol, and lowering blood triglycerides) and hypertension, and can also help control diabetes. This modest weight loss has also been shown to reduce the rate of developing type 2 diabetes in individuals at risk for the disease. That being said, a recent review and meta-analysis of the effects of weight loss on mortality risk concluded that intentional weight loss had a small benefit for obese individuals with associated risk factors, but had no longevity benefit for healthy individuals including the “healthy obese”. The healthy obese are those who can be categorized as obese yet do not have any associated risk factors. For this reason, it remains questionable whether weight reduction alone should be a goal of those who are fit, eat well, and are in overall good health despite being overweight. In addition, the long term deleterious health effects of frequent dieting and weight cycling may override the potential benefit of weight loss in heavy people who are otherwise healthy. Obviously, the major factor involved in weight loss is to eat fewer calories than are necessary to maintain one’s current weight, so that fat stores are mobilized to make up the difference. Everyone has a genetically determined set point – a weight range that one's system strives to maintain. This is often referred to as homeostasis. A person’s set point is influenced by behaviours and environment, and with persistent effort, can be lowered. Unfortunately, the metabolic changes that occur with weight loss contribute to the challenges many people have with maintaining a lower weight. In most cases, metabolic rate slows, reducing total energy expenditure and resulting in fewer calories being needed to sustain energy needs. However, if muscle mass can be retained, it is possible to maintain the previous metabolic rate, or perhaps increase it if additional muscle mass is gained through strength training. This is the most challenging aspect of losing weight – as weight is lost, hunger cues rise as a result of the body trying to maintain its homeostasis.
It takes a lot of commitment, and mental and physical energy, to lose weight and maintain the loss. Feelings of hunger, as well as environmental and emotional cues – taste, texture and the pleasure of eating – can override the best of intentions. As well, many people turn to food to deal with life stresses. Being ready to make a change is the first step, however, and we now have information on the behaviours of successful weight maintainers. The National Weight Control Registry (NWCR) tracks individuals who have been successful at losing weight and keeping it off for at least one year. Here is what they have in common:
- They monitor their weight and food intake. Most people grossly underestimate the number of calories they consume, and a record of food intake can be a useful management tool. This is one of the reasons that Weight Watchers has been successful for many people. It is much easier to alter or adjust behaviours when we have information to inform our choices. To avoid obsessing over weight, choose a day and time to weight yourself weekly, and tune into how your clothes fit each day. For women, taking note of the time in menstrual cycle can also provide information, as the common pre-menstrual symptom of water retention can add several pounds to one’s weight.
- They maintain a low calorie and low fat diet. It is well demonstrated by research that the larger the portion, the more the person will eat. Eating larger amounts at a given meal does not affect hunger and fullness ratings, and people rarely compensate by eating less at later meals. Pay attention to portion sizes, and eat slowly and mindfully. As well, increasing intake of fruits and vegetables helps control portion sizes – we eat according to the volume of the food, rather than how energy-dense it is. So in most cases a plate that is full with salad, a little brown rice, and a small amount of protein will induce the same feeling of fullness as a plate filled with French fries. A simple strategy is to serve meals on salad plates instead of dinner plates, and fill 1/2 of your plate with vegetables, 1/4 with carbohydrate, and 1/4 with protein.
- They eat breakfast every day. Skipping breakfast is associated with a higher body mass index and increased obesity risk. Because breakfast eaters maintain morning blood sugar levels, they are more likely to have better control over snack choices and eat less at later meals. Successful weight losers generally eat a breakfast that contains 20% of their daily energy intake. While it is true that total calories consumed during the day matter more than when they are eaten, there is evidence that eating more calories earlier in the day versus later may help people manage their weight. This is a central theme of the Mediterranean Diet, where the largest meal of the day is eaten at lunchtime, and dinner is light.
- They engage in 1 hour of physical activity daily. For most of the participants, this is walking at a brisk pace.
- They limit television/recreational screen time to 10 or fewer hours per week.
The obesity epidemic is multi-factorial – partly caused by a drastic, sudden shift to a sedentary lifestyle over the past 20 years, and a marked change in dietary habits in terms of what and how we eat . It will take the process of evolution thousands of years to catch up. The process of losing weight can be daunting, but by incorporating proven strategies and setting realistic goals, success can be achieved. This article was adapted from “Beyond Energy Imbalance”, published in the March 2010 issue of the IDEA Fitness Journal.