Make small diet tweaks to prevent adult weight gain
It’s estimated that adults gain, on average, one to two pounds a year. For some people, this gradual creep could lead to overweight or obesity.
Preventing weight gain is a fundamental objective of health authorities worldwide. Even modest annual weight gain in adults with overweight and obesity has been linked to an increased risk of chronic illness, including cardiovascular disease and cancer.
The good news: you don’t have to make major changes to your diet to prevent incremental weight gain. Instead, studies have found that adopting a “small change approach” – cutting 100 to 200 calories a day by eating less, exercising more or a combination of the two – can do the trick.
Weight gain prevention research
The latest study to investigate the small change approach, published earlier this year in the Canadian Medical Association Journal, involved 320 sedentary adults, average age 52, living with overweight or obesity.
Obese is defined as having a body mass index (BMI) of 30 or greater; a BMI of 25 to 29.9 is considered overweight. BMI is calculated as your weight in kilograms divided by the square of your height in metres. (Use an online calculator to determine your BMI.)
For the trial, participants were assigned to a small change approach (SCA) or monitoring alone (MA) for two years. Those in the SCA group were counselled to cut 100 calories from their daily diet and increase daily steps by 2,000 (about 20 minutes).
People in the MA (control) group were asked to maintain their usual diet and physical activity.
Both groups had their weight monitored regularly over the two-year study. Participants had their weight measured once again one year after the trial ended.
Compared with monitoring only, the small change approach led to a weight loss of two pounds (versus one pound) over the first 15 months of the study. At the two-year mark and one year later, prevention of weight gain did not differ between the two groups; both groups did not gain weight.
The finding that the MA group did not gain weight over the study surprised the researchers. One reason may be that simply having weight monitored on a regular basis can lead to positive behavioural change. It’s also possible that being in a study can cause people to do better.
When the researchers looked at overweight participants (versus participants with obesity), however, they found that weight gain was prevented in the SCA group while the MA group gained weight. These findings are consistent with those of a 2016 trial conducted in 599 young adults with overweight.
The latest study enrolled prominently white people and 77 per cent were female so the findings may not be transferable to other groups.
Advantages of the ‘small change approach’
Making small tweaks to diet and exercise is easier to integrate into your everyday life and maintain long-term than bigger lifestyle changes required to lose weight.
A number of randomized controlled trials have found that large dietary changes are effective for short-term weight loss but, over time, weight regain is common.
A more reasonable and achievable goal, many experts contend, may be to focus on preventing weight gain.
According to Dr. Robert Ross, the lead study author and professor in the School of Kinesiology and Health Studies at Queen’s University, Kingston, Ont., “preventing people moving from overweight to obesity is associated with health benefits regardless of your body weight.”
For Canadians to adopt the small change approach, though, requires a change in expectations. “If we can make subtle and sustainable changes – eating a healthy diet, sitting less, moving more – and appreciate that preventing weight gain is associated with health benefit, then we’ve made progress”, says Dr. Ross.
Easy calorie cuts that make a difference
To prevent weight from creeping up, aim to cut 100 to 200 calories daily through diet, exercise or both.
For example, eat one medium orange instead of drinking 12 ounces of orange juice to save 117 calories. Skip the cheese slice on your sandwich to drop 115 calories. Reduce your portion size of brown rice by one-half-cup to lose 128 calories.
Add one less tablespoon of cooking oil when sautéing and save 120 calories. Try 2% milk instead of 10% cream in your coffee to cut 80 calories per one-quarter-cup.
Twenty minutes of brisk walking, 12 minutes of hiking, 10 minutes of moderate cycling and 8 minutes of swimming (breaststroke) all burn roughly 100 calories for a 170-pound person.
Leslie Beck, a Toronto-based private practice dietitian, is director of food and nutrition at Medcan. Follow her on Twitter @LeslieBeckRD
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