Lifestyle Interventions to Stem the Tide of Type 2 Diabetes

Abstract

Worldwide, the number of persons with diabetes and those who are at risk for diabetes is increasing at an alarming rate, largely driven by the rising prevalence of obesity and inactivity. Of concern in the United States are the approximately 86 million people who have prediabetes and one in three people with metabolic syndrome (Prevalence of metabolic syndrome among adults 20 years of age and over, by sex, age, race and ethnicity, and body mass index: United States, 2003–2006, Hyattsville, 2009). These individuals are at high risk for conversion to type 2 diabetes and for cardiovascular disease if lifestyle prevention strategies are not implemented. After years of rises in the incidence of diabetes, one positive finding has been the reporting of a leveling off in the prevalence from 2009 to 2014 in the 45–64 years age group, although an upward trend is still evident in older age groups (http://www.cdc.gov/diabetes/statistics/prev/national/figbyage.htm).

Preventing obesity is a high priority for the prevention of type 2 diabetes as many individuals are overweight or obese at the onset. However, the disease can also be diagnosed in nonobese individuals, while many obese people never develop it. Therefore, it is likely that genetic predisposition and lifestyle choices are important factors in the development of type 2 diabetes. Cereal fiber and magnesium, both components of whole grains, and fruit and green leafy vegetable intakes are consistently associated with lower risk of developing type 2 diabetes (J Nutr 142:1304–1313, 2012; Diabetes Care 34:2116–2225, 2011; BMJ Open 4:e005497, 2014) with a possible protective role for low-fat dairy foods (Am J Clin Nutr 103:1111–1124, 2016). Remaining physically active is important as sedentary time is associated with an increased risk of developing type 2 diabetes (Diabetologia 55:2895–2905, 2012). These risk factors, both non-modifiable (genetics and aging) and modifiable (central obesity, sedentary lifestyle, and diet), have been identified as contributing to insulin resistance, a common factor in the development of diabetes and cardiovascular disease. However, elevated plasma free fatty acids (lipotoxicity) may also be a common denominator and this is generally associated with obesity and, in particular, intra-abdominal obesity. Measurement of waist circumference may help identify individuals at risk. Large clinical trials have demonstrated the role of nutrition therapy including both modest weight loss and increased physical activity in the prevention or delay of type 2 diabetes (N Engl J Med 344:1343–50, 2001; N Engl J Med 346:393–403, 2002; Diabetes Res Clin Pract 2005;67:152–162; Diabetologia 2006;49:289–297).