Low-oxygen nights plus weight loss to improve iron absorption in adults with obesity
Effects of Energy Restriction and Intermittent Hypoxia on Iron Absorption in Obesity
This trial will test whether losing weight on a controlled diet combined with sleeping in a low-oxygen tent at night can increase iron absorption in adults with obesity.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 30 (estimated) |
| Ages | 22 Years to 65 Years |
| Sex | All |
| Sponsor | Pennington Biomedical Research Center Academic / other |
| Locations | 1 site (Baton Rouge, Louisiana) |
| Trial ID | NCT07542873 on ClinicalTrials.gov |
What this trial studies
Adults with obesity are randomized in a double-blind, parallel-arm design to 8 weeks of controlled-feeding energy restriction (-500 kcal/day) while spending 8 hours per night in either a normobaric hypoxia (15% FiO2) or normoxia (21% FiO2) in an in-home tent. The protocol pairs diet-induced reduction in inflammation with nightly low-oxygen exposure to stimulate erythropoiesis and suppress hepcidin, a regulator that limits iron absorption. Outcomes include measures of dietary iron absorption and biomarkers of iron metabolism and inflammation. The trial builds on prior evidence that hypoxia can increase iron availability but applies it specifically to the context of weight loss in people with obesity.
Who should consider this trial
Good fit: Ideal candidates are adults with obesity (BMI 30.0–39.9 kg/m2) who live in the Baton Rouge area, were born at low altitude, are willing to follow an 8-week controlled diet, and can sleep 8 consecutive hours nightly in a supplied hypoxic tent while avoiding tobacco and certain medications.
Not a fit: People outside the BMI range, those with medical conditions or medications that affect oxygen delivery or erythropoiesis, residents or recent travelers to high altitude, or those unable to use the home tent are unlikely to benefit or be eligible.
Why it matters
Potential benefit: If successful, this approach could raise iron absorption and improve iron status in people with obesity without relying solely on high-dose supplements.
How similar studies have performed: Low-oxygen exposure has been shown in other settings to increase erythropoiesis and iron absorption, but combining intermittent normobaric hypoxia with diet-induced weight loss in obesity is a novel application.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: * Obese (BMI between 30-39.9 kg/m2) * Born at altitudes below 2,100 meters (\~7,000 feet) * Currently residing in Baton Rouge, Louisiana or surrounding area * Not taking any medication(s) that interfere with oxygen delivery/transport for 4 weeks prior to and throughout the entire study (e.g., includes sedatives, sleeping aids, tranquilizers and/or any medication that depresses ventilation, diuretics, alpha and beta blockers). * Willing to refrain from smoking, vaping, chewing tobacco, and dietary supplement use throughout the entire study. * Willing to have a hypoxic tent set-up in their home and spend 8 consecutive hours per night in the tent for 8 weeks Exclusion Criteria: * Living in areas that are more than 1,200 m (\~4,000 feet), or have traveled to areas that are more than 1,200 m for five days or more within the last 2 months * Cardiovascular abnormalities, gastrointestinal disorders, or any condition that interferes with oxygen delivery/transport (e.g., kidney disease, cardiovascular disease, etc.) * Oxygen saturation \< 95% while awake or oxygen saturation dips below 88% for a total of ≥ 10 min overnight in normoxic conditions * Evidence of apnea or other sleeping disorders * Evidence of prior high-altitude pulmonary edema (HAPE) or high-altitude cerebral edema (HACE) diagnosis * Diagnosis or family history of sickle cell anemia/trait * Hematocrit \<42% for males, \<36% for females * Hemoglobin \<13 g/dL for males, \<12 g/dL for females * Blood donation within 8 weeks of beginning the study * Present condition of alcoholism, anabolic steroids, or other substance abuse issues * Women who are pregnant, lactating, planning to become pregnant, or who have had an irregular menstrual cycle in the past 6 mo. * Weight gain or loss \> 10% of body weight during the past 6 months * Adults unable to consent
Where this trial is running
Baton Rouge, Louisiana
- Pennington Biomedical Research Center — Baton Rouge, Louisiana, United States (Recruiting)
Study contacts
- Principal investigator: Camila Weschenfelder, PhD — Pennington Biomedical Research Center
- Study coordinator: Recruitment Core
- Email: clinicaltrials@pbrc.edu
- Phone: 225-763-3000
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.