Keeping a food diary may be the best kept secret to sustaining weight loss over the long term. Last year, nearly 1,700 study participants agreed to exercise and adopt a healthy diet, but those who kept a daily food diary lost twice as much weight as those who didn’t. Putting a nail in the coffin of the too easily-concluded idea that prolonged lifestyle change and long-term weight loss is difficult or impossible, the study, published in the American Journal of Preventive Medicine, showed that nearly 70 percent of participants were able to lose body weight significant enough to make improvements to their health. Two-thirds of the subjects lost 9 pounds or more over the course of six months, but diary-keepers averaged, at an average of 20 pounds of weight loss, over double that number. There appears to be a mechanism of accountability that genuinely keeps dieters from over-consuming when they are required to record every morsel of intake.
In addition to accountability, diary-keeping promotes awareness of the caloric values in foods that might otherwise sneak under the radar. One study participant was quoted as saying that bagels, for example, “are much higher in calories than you think they are.” And at the National Heart, Lung and Blood Institute in Bethesda, MD, researchers report that diary keeping can help identify and quarantine times when a person is eating out of boredom or due to stress. Mindful eating, long touted as a way to keep excess pounds away, is promoted by daily recording of food intake in a way that even the best intentioned but ill-monitored diets do not.
The study participants were overweight or obese, with an average age of 55 years. They were asked to write down anything they ate or drank that had calories. They attended weekly sessions that encouraged calorie cutting and promoted 30 minutes of exercise per day. Most people only consume 40 to 50 different foods on a regular basis, so once the initial work of counting has been done, the groundwork is laid for an easy informal mental tally that yields great dietary accountability.
A slower, more stable overall lifestyle change is clearly more effective than crash diets with a perceived goal and then perceived end. Logging calories in a daily journal helps ensure that large dietary fluctuations are minimized. More research is needed to find the most effective mechanisms to keep people recording their daily intake. When a dieter deviates for too long from the program, weight loss can abruptly slow or stop altogether.
Research as of late has generally buttressed a long-suspected shortcoming with what dieticians refer to as restrained eating. Attempting to cognitively control intake by imposing strict rules on food types and calories allowed has been associated with feelings of extreme deprivation and weight gain, not weight loss. Unrestrained eaters are better at evaluating fullness and monitoring food intake based on hunger than people with deprivation anxieties. In 2008 to separate studies found that exposure to palatable food under restricted conditions stimulates either overeating of the restricted food or compensates with increased intake of allowed foods. In either scenario, dietary intake often exceeds dietary need, leading to weight gain rather than weight loss. Reliance solely on willpower appears to make resisting food temptations much more difficult.
Your food diary might include: type and amount of food eaten, calories, time of intake, hunger level, emotions at the time of eating, and activities during or even simply associated with it. One of the most powerful and simple tools in long-term weight management is asking yourself why you are eating. And recording the type and amount of one’s physical activity on a daily basis can help on the other side of the energy equation.
In addition to food-diary keeping, other effective weight loss tactics include keeping a large supply of only healthy foods available, spending more time with active and healthy people, and restricting eating to the dining room, and in planned portions.
The National Heart, Lung and Blood Institute website offers free meal planners, complete with calorie listings and automatic calorie counters for the most popular foods. Visit http://hp2010.nhlbihin.net/menuplanner/menu.cgi for more information.
(ACE Fitness Matters, 2008, Vol. 14, No. 6, pp. 6-7; 2008, Vol. 14, No. 4, pp. 4-5; NHLBI, www.nhlbi.nih.gov)
