A 2005 report in the New England Journal of Medicine warned that rising obesity rates could reverse two centuries of increasing life expectancy in the United States. Longevity researcher S. Jay Olshansky predicted that unless trends changed, the average lifespan could fall by two to five years within a few decades.

Nearly twenty years later, the concern is no longer theoretical.
U.S. life expectancy has declined—and obesity is one of several contributing factors.

Life Expectancy Has Fallen Since 2014

For most of modern history, Americans lived longer each generation. That trend flattened around 2010 and reversed after 2014. According to the CDC:

  • U.S. life expectancy peaked at 78.9 years in 2014

  • It fell to 76.4 years in 2021 (a drop of ~2.5 years)

  • It remains below pre-2014 levels

Although the biggest immediate drivers of the drop were COVID-19, drug overdoses, and chronic disease, researchers note that obesity and metabolic disease have weakened baseline health in younger and middle-aged adults—amplifying the downward trend.

This matches what Olshansky predicted: younger generations experiencing more chronic disease at earlier ages, reducing long-term survival.

Childhood Obesity Has Increased Since the Original Article

Your original numbers were:

  • 15% of school-age children obese

  • Childhood obesity doubled in 25 years

  • 30% overweight

Current numbers (CDC 2017–2020):

  • 19.7% of U.S. children ages 2–19 are obese

  • That’s 14.7 million children and teens

  • Severe obesity continues to rise fastest

These chronic issues—insulin resistance, fatty liver, early hypertension—now appear in children as young as 8–10, which was rare in 2005.

Screen Time, Sedentary Living, and Food Marketing: Still True, Now Worse

The amount of time children spend viewing media (TV, video games, computer use) parallels the increase in the number of overweight children, according to a report issued by the Kaiser Family Foundation (Publication Number: 7030 Publish Date: 2004-02-24). Things have gotten worse since the 2004 report.

  • Children now average 7.5 hours/day of combined screen time

  • Food marketing to children remains dominated by high-sugar, high-fat, ultra-processed products

  • Heavy screen time is strongly linked to obesity risk, poor sleep, and metabolic problems

 

Obesity and Cancer:  

In 2005, these cancers were linked to obesity:

  • Breast (postmenopausal)

  • Colon

  • Endometrium

  • Kidney (renal cell)

  • Esophageal adenocarcinoma

Current research has expanded the list of cancers linked to excess body fat:

  • Pancreatic cancer

  • Gallbladder cancer

  • Ovarian cancer

  • Multiple myeloma

  • Liver cancer

  • Meningioma

  • Thyroid cancer (some studies)

Bringing It Together: How to Reconcile the 2005 Article With Today’s Reality

Since this original report was published in 2005, U.S. life expectancy has begun to decline—a trend not seen in modern history. Although multiple factors contribute (including chronic disease, metabolic dysfunction, and social determinants of health), rising obesity rates—especially in children—are recognized as a major long-term driver. In many ways, the concerns raised in the 2005 NEJM article have already materialized, underscoring the importance of nutrition, movement, and healthy environments for today’s children.