A ‘Small-Changes’ Approach
If indeed most individuals are more responsive to approaches to encourage small changes to improve health behaviors, this would inform the public health promotion of nutrition and physical activity. In the context of weight management, this could result in the translation of knowledge to improve the design of interventions for the benefit of mothers, their children, and the wider family.
The paper by Hill et al. [17 ]published in Science and a later publication [21] suggested that there was an urgent need to push back against the many environmental factors responsible for the gradual weight gain of the population. Rather than focus on weight loss per se, or the prevention of obesity, Hill et al.[17] suggested that initial efforts should focus on promoting small lifestyle changes to eliminate or reduce ‘incremental weight gain’. This was not the first attempt to promote small behavior changes, however, in the context of obesity, Hill [21] contended the following:
– Compared to large changes, small changes are more realistic, feasible to achieve and maintain. Consistent with the literature, a daily caloric deficit of 200 kcal or less may have the advantage of minimizing the decrease in metabolic rate typically associated with weight loss and also not increase hunger [22]. Increasing energy expenditure by 100 kcal over the course of a day is also not associated with feelings of fatigue or increased drive to eat [23].
– Small changes in diet and/or physical activity, despite being less than the public health recommendations, may be sufficient to prevent gradual weight gain.
– If self-efficacy is enhanced as a function of achieving small lifestyle changes, this may foster additional changes and ultimately lead to larger changes. (We recognize that self-efficacy may also be enhanced through rapid short-term weight loss but weight lost using this approach is typically regained over time.)
– The ‘small-changes’ approach could be used to help reduce environmental forces that promote increases in energy intake and decreases in physical activity.
The argument for a ‘small-changes’ approach is also based on the observation that many individuals gain weight gradually over an extended period, the so-called creeping obesity. Small daily discrepancies in energy balance (the ‘energy gap’) could be countered by small increases in energy expenditure or decreases in energy intake by 100 kcal per day. Detailed information regarding the ‘energy gap’ concept can be found in a number of papers [21,24,25].
Since 2003, the ‘small-changes’ approach has gained considerable traction in numerous government and non-government initiatives. The ‘small-changes’ initiative of the US Department of Health and Human Services’ included television and radio commercials and a website (www.smallstep.gov). The approach was also promoted by the US Surgeon General (www.surgeongeneral.gov/initiatives/prevention/index.html), and recommended by the American Diabetes and Heart Associations as well as American Cancer Society.
America On the Move (AOM) (www.americaonthemove.org) was formed to promote the ‘small-changes’ approach to prevent weight gain and improve health. The starting goal is to increase activity level by 2,000 steps per day and decrease energy intake by 100 kcal per day. The use of this approach in the Colorado On The Move program resulted in significant increases in daily walking [26].
The efficacy of AOM in the prevention of weight gain was tested in two family-based interventions [27,28]. In the first, families were asked to make two small changes to daily routines, i.e. consume cereal for breakfast and increase physical activity by 2,000 steps per day [27]. There was a significantly lower increase in BMI-for-age for intervention versus control children over 14 weeks and intervention group mothers also reduced their BMI level.
In the second intervention [28], energy intake was reduced by 100 kcal per day by replacing sugar and sugar-containing beverages with artificial sweeteners or products containing artificial sweeteners (but no calories). Intervention families were also asked to increase daily steps by 2,000 (over the baseline number). Significantly more children in the intervention group maintained or decreased BMI-for-age across the 6-month intervention.
Stroebele et al. [29] evaluated the short-term effectiveness and usefulness of the AOM message by providing 100 simple tips to decrease food intake by 100 kcal per day. Energy intake was reduced more at the meals where tips were used which underlined the feasibility and ease of understanding of the ‘small-changes’ approach. However, major limitations of the study were the small sample and short duration.
Evidence for small changes in relation to weight loss stems from the ASPIRE trial [30] in which overweight and obese sedentary adults randomized to a 16-week intervention lost significantly more weight than both the standard didactic or control group. Despite the modest weight loss (average of 4.62 kg) in the ‘small-changes’ group, it was clinically significant (5% of body weight). The ‘small-changes’ group also maintained weight loss, decreased waist circumference, and abdominal fat loss at 3 months post-intervention. Similar results were also reported in a 12-week ‘small-changes’ telephonic intervention in sedentary obese veterans [31]. Findings from other community-based studies [32] support the benefits of small diet- and physical activity-related lifestyle change and a healthy body weight.
Most food industry interest in the ‘small-changes’ approach has related to portion size and the increased popularity of 100-kcal snacks, however, more research is needed in this area [21]. Lloyd-Williams et al. [33] examined the potential public health impact on coronary heart disease and stroke mortality of replacing one ‘unhealthy’ snack with one ‘healthy’ snack per person, per day across the UK population. They reported that small changes to diet (such as choosing healthy snacks) could lead to potentially large reductions in cardiovascular deaths. Readers are referred to a number of reviews in relation to physical activity interventions designed to increase the number of steps per day [34,35]. Typically, pedometers have been used to motivate and also quantify steps per day.
In the school setting, the Take 10 Program is a ‘small-changes’ approach designed to increase activity energy expenditure across the academic curriculum rather than rely on physical education and sport for extra energy expenditure (www.take10.net). A recent school-based intervention using pedometers and e-mail support was successful in promoting physical activity and selected healthy eating behaviors in adolescent boys and girls [36].
Despite lengthy periods of inactivity, many individuals make unrealistic and/or large changes in energy expenditure on commencement of an activity program. The risks of such an approach include soreness, discomfort, injury, and reduced motivation to exercise. Large increases in physical activity energy expenditure may not be accompanied by a concomitant negative daily energy balance [37,38], primarily due to an increase in energy intake. A parallel from a dietary perspective is the inability to sustain a significant restriction in energy intake, particularly when food is unpalatable.
Given the extent of global overweight and obesity, it has been postulated that sweeping changes in policy, food supply, and environment are needed to arrest and reverse the epidemic [39]. The ‘small-changes’ approach is not at odds with such claims nor is it seen as the panacea for the obesity problem. Rather, the ‘small-changes’ approach is one of many needed in a multi-disciplinary, multi-sectoral approach to the prevention and management of obesity. Nader et al. [40] suggested that approaches begin as early as possible and use a systems framework to both implement health behavior and environmental changes in communities.
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