Obese people can improve health without weight loss, study finds

Obese adults who follow lifestyle-based diet programs can significantly improve their health, and some even see improvements without shedding the pounds, according to a new study out of York University led by Professor Jennifer Kuk of the School of Kinesiology & Health Science in the Faculty of Health.

The study, “Influence of a Lifestyle-Based Weight Loss on the Metabolic Risk Profile of Metabolically Normal and Abnormal Obese Adults”, published online Jan. 17 in the journal Obesity, examined a sample of 392 metabolically normal and abnormal obese patients attending JenniferKukthe Wharton Medical Clinic, a referral-based weight-management clinic in Halton and Hamilton.

Jennifer Kuk

“The purpose of this study was to examine the differential effects of weight loss on the health risk profile among overweight and obese individuals who have common health problems (metabolically abnormal obese) or are healthy despite being overweight (metabolically normal obese),” says Kuk. “It has been well-established that a five to 10 per cent reduction of initial body weight can improve metabolic health in those who have health problems. However, whether or not weight loss can further benefit those who are ‘healthy’ is unclear.”

Metabolically normal obese individuals are people who exhibit normal blood pressure, high levels of insulin sensitivity, normal blood glucose and a favorable lipid profile. Metabolically abnormal obese individuals are defined as those having one or more common cardiovascular or diabetes risk factors (i.e. high glucose, triglycerides, blood pressure or low-density lipoprotein cholesterol).

During the study, patients were tracked for three or more months of attending the clinic. At the initial visits, patients completed a comprehensive medical history questionnaire and diagnostic testing. Patients then met with a doctor and bariatric educator to review and follow-up on health conditions, weight-loss progress, exercise regime and prescribed meal plan. Patients were also encouraged to perform additional weekly self-weigh-ins and attend additional health education sessions administered by doctors, dietitians, behavioural therapists and exercise specialists.

At the end of the study, researchers found that both metabolically normal and abnormal individuals showed significant improvement to their health after a five per cent loss of their initial body weight. However, the results also showed that metabolically abnormal obese individuals, who did not achieve the five per cent weight loss, still significantly improved blood pressure and cholesterol levels.

“This study shows that the positive lifestyle modifications associated with attempting to lose weight may be associated with improvements in metabolic health, even in the absence of weight loss,” says Kuk. “This is extremely important given that most individuals who try to lose weight are unable to sustain their weight loss over the long term, and that this repeated cycling of body weight up and down may in fact have negative health effects. Thus, the take home message is to try to improve your health by eating better and moving more, not by just losing weight.”