The Scientists Who Built the Modern Snack

The Scientists Who Built the Modern Snack

From Fork U with Dr. Terry Simpson by Terry Simpson

June 11, 2026 · 14 min · Episode 131

About this episode

This episode discusses a landmark study on the effects of ultra-processed foods on calorie intake and obesity.

How We Eat Most of us think we know what we eat. However, nutrition researchers have learned a frustrating lesson over the years: asking people what they ate yesterday is often less accurate than anyone would like. Although food diaries and surveys can provide useful information, memories are imperfect, snacks are easily forgotten, and portion sizes tend to grow smaller in retrospect. Consequently, some of the most important nutrition research takes place in a setting that is both expensive and surprisingly simple—a metabolic ward, where every meal is prepared, every serving is weighed, and every leftover bite is measured. That approach is exactly what researcher Kevin Hall and his colleagues used in a landmark study at the NIH. Participants were given two different diets, one based largely on ultra-processed foods and another built around minimally processed foods. Importantly, the volunteers could eat as much as they wanted. Nobody instructed them to count calories, restrict portions, or lose weight. Nevertheless, participants consumed about 500 more calories per day when eating the ultra-processed diet. The same people, living in the same environment, produced dramatically…

People in this episode

Host: Terry Simpson

Topics covered

  • nutrition research
  • ultra-processed foods
  • calorie intake
  • obesity
  • metabolic ward

Keywords

  • nutrition
  • calories
  • ultra-processed foods
  • obesity
  • metabolic ward
  • diet
  • food research

Mentioned in this episode

Organizations: NIH

More episodes of Fork U with Dr. Terry Simpson

Explore listener stats, chart rankings, contacts and more on the Fork U with Dr. Terry Simpson podcast page.