Over the last 20 years, there has been a frightening increase in the number of Americans that are obese or overweight.  Data from the National Health and Nutrition Examination Survey (NHANES), has tracked the rise in obese and overweight adults since 1999.   Using BMI, or Body mass Index, the survey found that 32% of men and 35% of women were classified as obese; having BMI’s exceeding 30.  BMI is an inexact measure and may actually underestimate the number of people at risk for adverse health outcomes such as cardiovascular disease, diabetes metabolic syndrome and certain cancers.  Some studies suggest that half of the people with a normal BMI (less than 25) may have an elevated body fat percentage.  Confirming this trend is a recent study by the Centers for Disease Control that estimated the body fat percentage of a typical American woman to be 40% and the typical American man at 28% based on a six year analysis of data.[1]  These body fat measurements are significantly higher that what are considered ideal.

During that same time period we have witnessed an alarming increase in the number of individuals diagnosed with type 2 diabetes.  During these past two decades, the diabetes-related death rate climbed by 45% in contrast to declining death rates for cardiovascular disease and cancer.  An estimated 57 million Americans are risk for diabetes with another 24 million  adults and children are already diagnosed with the disease.[2]  Of all of the medical conditions directly linked to obesity, diabetes appears to be most closely linked.  Even as science searches for more clues about the causes of diabetes and medications to prevent it, the vast majority of new cases of the disease in older adults could be prevented by following a modestly healthier lifestyle, according to research led by scientists at the Harvard School of Public Health (HSPH).   The findings highlight that diabetes really is a lifestyle disease and is largely preventable, by modifying five lifestyle factors:  physical activity, diet, smoking habits, alcohol use, and amount of body fat.[3]  Although this study was conducted on adults over age 65, several studies have similarly linked these factors with diabetes risk on an individual basis.

The cost to our healthcare system is staggering: $147 billion was spent in 2009 on diabetes and $174 billion on obesity related medical care.  For an individual diagnosed with diabetes, their average medical expenditures are 2.3 times greater than those without the disease.  Type 2 diabetes is the most common form of the disease.  It was traditionally know as “adult onset diabetes” but the recent obesity epidemic and increasingly sedentary lifestyle has resulted in increasingly younger individuals being diagnosed.

Tracking blood sugar has traditionally been the standard test to detect risk for diabetes.  Recently a better diagnostic indicator of the risk for developing diabetes was recommended as a routine screening test by a committee of international experts at the American Diabetes Association’s 69th Scientific Sessions in 2009.  This test, called the hemoglobin A1C (HbA1C) assay, measures the average blood sugar reading for the previous 3 months.   Even more important than just measuring the risk for diabetes, measurement of HbA1C more accurately identifies individuals at increased risk for adverse clinical outcomes, such as cardiovascular disease, stroke and all cause mortality than fasting glucose measurements.[4]  When there are excess sugars in the blood, the sugar can attach to many of the body’s proteins and enzymes in a process called glycation.  Those glycated proteins interfere with normal cellular functions and eventually lead to widespread damage in nearly every organ of the body.

Measuring and managing blood sugar levels alone is, however, not the end game.  In type 2 diabetes, and many of its complications, insulin resistance plays a crucial role.  With chronically elevated blood sugar, your body produces more and more insulin in an attempt to deal with the excess sugars.  Over time, the insulin receptors become less responsive to the effects of insulin.  This in turn allows blood glucose to continue to rise until the diagnosis of diabetes is made.  But simply undertaking pharmacologic strategies to lower blood glucose without addressing insulin sensitivity can lead to an increased risk of death from cardiovascular disease.[5]  Insulin resistance is associated with increased LDL cholesterol, increased triglycerides and lower HDL cholesterol.[6]  The best way to manage type 2 diabetes and pre-diabetes is to improve the body’s sensitivity to insulin.

Physical activity and weight loss (or more accurately fat loss) helps the body respond better to insulin.  By losing body fat, especially abdominal fat, and being more physically active, people with insulin resistance or pre-diabetes may avoid developing type 2 diabetes.  Staying physically active can also help prevent serious diabetes complications and even reverse type 2 diabetes.

Obesity facts:[7]

  • Approximately 300,000 deaths each year in the United States may be attributable to obesity.
  • Overweight and obesity are associated with heart disease, certain types of cancer, type 2 diabetes, stroke, arthritis, breathing problems and psychological disorders, such as depression.
  • 40% of adults in the United States do not participate in any leisure-time physical activity.
  • Less than 1/3 of adults engage in the recommended amounts of physical activity

Diabetes facts:[8]

  • 67% of diabetics die prematurely from heart disease or stroke
  • 60% to 70% have nerve damage leading to other health concerns such as sexual dysfunction, feet and hand pain, impaired digestion
  • Ten times higher rate of amputations
  • Leading cause of blindness and kidney failure

Adopting a healthier lifestyle could prevent the majority of type 2 diabetes cases.  It isn’t just coincidental that the same healthy lifestyle modifications could prevent more than 80% of cardiovascular disease cases and virtually curtail the obesity epidemic.  It is a commitment and a forward looking approach to living.  How you choose to live now will directly impact how you feel and function in the decades to come.  Start living better.

[1] Li C. Ford E. et al.  Estimates of body composition with dual-energy x-ray absorptiometry in adults.  Am J Clin Nutr 90: 1457-1465, 2009. First published October 7, 2009; doi:10.3945/ajcn.2009.28141

[2] Centers for Disease Control and Prevention, http://www.cdc.gov/media/pressrel/2008/r080624.htm

[3] Mozaffarian D, Kamineni A, et al. Lifestyle Risk Factors and New-Onset Diabetes Mellitus in Older Adults: The Cardiovascular Health Study Arch Intern Med. 2009;169(8):798-807

[4] Selvin E, Steffes MW, Zhu H, Matsushita K, Wagenknecht L, Pankow J, Coresh J, Brancati FL. Glycated Hemoglobin, Diabetes, and Cardiovascular Risk in Nondiabetic Adults. New England Journal of Medicine, 2010; 362 (9): 800

[5] Jenny-Avital E. R., Luan F. L., Nguyen K., et al. Intensive Glucose control in type 2 diabetes. N Engl J Med 2008; 359:1519-1521, Oct 2, 2008.

[6] Knopp R, Retzlapp B, Fish B, et al. Effects of insulin resistance and obesity on lipoproteins and sensitivity to egg feedings. Arteriosclerosis, Thrombosis, and Vascular Biology. 2003;23:1437-1443.

[7] www.surgeongeneral.gov

[8] http://www.cdc.gov/diabetes/statistics/complications_national.htm