Effect of Ultra Processed Versus Unprocessed Diets on Energy Intake

Overconsumption of foods that result from extensive industrial processing is believed to
contribute to the development of obesity. Ultra-processed foods now represent most of the
calories consumed in America and their contribution to overall diet has increased in parallel
with the rise in the prevalence of obesity over the past several decades. While such
correlations are suggestive, the effect of industrial processing per se, independent of
dietary macronutrient composition, on ad libitum energy intake has not been carefully
investigated. Therefore, we will conduct a feeding study in 20 adult men and women to
investigate the differences in ad libitum energy intake resulting from consuming two test
diets for a pair of 2-week periods in a randomized, crossover design during a single 4-week
period. The test diets presented to participants will be matched for calories, macronutrient
composition, sugar, fiber, and sodium, but one diet will be composed of ultra-processed foods
whereas the other diet will be unprocessed foods.

- INCLUSION CRITERIA:

1. Adults age 18-50 years, male and female

2. Weight stable (< +/- 5 % over past 6 months)

4. Body mass index (BMI) greater than or equal to 18 kg/m^2

5. Willing to cease their habitual caffeine intake during the study, beginning one
week prior to inpatient admission

6. Written informed consent

7. Willing to eat the food provided in the study

8. Able to complete daily bouts of stationary cycling at a moderate rate and intensity
with a HR equal to or greater than 0.3x(220-age-HR(rest))+HR(rest) but not exceeding
0.4x(220-age-HR(rest))+HR(rest) and no signs of arrhythmia

EXCLUSION CRITERIA:

1. Evidence of metabolic or cardiovascular disease, or disease that may influence
metabolism (e.g. cancer, diabetes, thyroid disease)

2. Taking any prescription medication or other drug that may influence metabolism (e.g.
diet/weight-loss medication, asthma medication, blood pressure medication, psychiatric
medications, corticosteroids, or other medications at the discretion of the PI and/or
study team)

3. Hematocrit < 34% (women only)

4. Hematocrit < 40% (men only)

5. Pregnancy, lactation (women only)

6. Participating in a regular exercise program (> 2h/week of vigorous activity)

7. Caffeine consumption > 300 mg/day

8. Regular use of alcohol (> 2 drinks per day), tobacco (smoking or chewing)
amphetamines, cocaine, heroin, or marijuana over past 6 months

9. Eating disorders or psychological conditions, such as (but not limited to)
claustrophobia, clinical depression, bi-polar disorders, that would be incompatible
with safe and successful participation in this study, as determined by investigators.

--Past or present history of claustrophobia since part of the protocol will involve
being confined to a small room for whole-body indirect calorimetry and being in an MRI
scanner for liver fat measures

10. Implants, devices, or foreign objects implanted in the body that interfere with the
Magnetic Resonance procedures

11. Volunteers with strict dietary concerns (e.g. vegetarian or kosher diet, food
allergies)

12. Volunteers unwilling or unable to give informed consent

13. Non-English speakers due to unavailability of required questionnaires in other
languages.