Improved Iron Status, but Not Protein Source, Is Related to Appetite, Satiety, and Mood in Women of Reproductive Age With Iron Deficiency: A Randomized Controlled Trial.

2026-06
The Journal of nutrition 156(6)
- Stephen R Hennigar
- Katelyn M Miller
- Robert D Murphy
- Amy Braymer
- Christy L Mayet
- Frank L Greenway
- Susan N Cheung
- Camila Weschenfelder
- Claire E Berryman

PubMed: 42061720
DOI: 10.1016/j.tjnut.2026.101559

Study Design

Type: Randomized Controlled Trial (RCT)
Population: 52 nonpregnant WRA (24 ± 7 y; BMI: 22.9 ± 3.0 kg/m2) with ID (serum ferritin: 13.7 ± 6.0 μg/L)
Methods: randomized, double-blind, parallel-arm study; consumed an iron supplement with a lunch meal containing either 4 oz. of beef (Animal) or Beyond Meat (Plant) once a day for 8 weeks
Blinding: Double-blind
Duration: 8 weeks
Funding: Unclear

Background

Iron deficiency (ID) is associated with decreased appetite and altered mood, which can contribute to feelings of early satiety and reduced overall well-being. Few studies have examined differences in appetite, satiety, and mood between meals containing animal meat and plant-based meat, or whether improving iron status in those with ID improves these outcomes.

Objectives

The objective of this study was to determine appetite, satiety, and mood after consumption of a meal containing animal meat or plant-based meat at baseline and after consuming the meal with an iron supplement once a day for 8 weeks in women of reproductive age (WRA) with ID.

Methods

In this randomized, double-blind, parallel-arm study, 52 nonpregnant WRA (24 ± 7 y; BMI: 22.9 ± 3.0 kg/m²) with ID (serum ferritin: 13.7 ± 6.0 μg/L) consumed an iron supplement with a lunch meal containing either 4 oz. of beef (Animal) or Beyond Meat (Plant) once a day for 8 weeks. Meals were calorically matched but differed in macro- and micronutrient composition due to the inherent differences between protein sources. For this secondary analysis, at baseline and endpoint, fasted participants consumed a standardized lunch meal containing beef or plant-based meat and rated appetite (fullness, hunger, desire to eat, and prospective consumption) using 100 mm visual analog scales. A composite satiety score was calculated. The Profile of Mood States questionnaire was assessed at baseline and endpoint.

Results

Indicators of iron status and anemia improved after 8 weeks (P < 0.05 for all) but did not differ between Animal and Plant. Hunger and desire to eat decreased, and fullness and composite satiety score increased after the meal (P-time < 0.0001 for all). Measures of appetite, satiety, and mood did not differ between Plant and Animal at baseline or endpoint. Changes in transferrin saturation (r = 0.4, P < 0.01) and hemoglobin (r = 0.3, P = 0.04) and hematocrit (r = 0.3, P = 0.03) were positively associated with changes in prospective food consumption, and changes in transferrin saturation were negatively associated with satiety (r = -0.3, P = 0.02). Changes in transferrin saturation (r = 0.3, P = 0.03) and hematocrit (r = 0.3, P = 0.05) were positively associated with change in anger/hostility.

Conclusions

These findings indicate that improvements in iron status, but not differences in protein source, affect appetite, satiety, and mood in WRA with ID. This trial was registered at Clinicaltrials.gov as NCT04793906.

Research Insights

Iron→Improved Fullness
Hunger and desire to eat decreased, and fullness and composite satiety score increased after the meal (P-time < 0.0001 for all).
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Improved Iron Status
Indicators of iron status and anemia improved after 8 weeks (P < 0.05 for all) but did not differ between Animal and Plant.
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Improved Satiety Score
Hunger and desire to eat decreased, and fullness and composite satiety score increased after the meal (P-time < 0.0001 for all).
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Increased Anger/Hostility
Changes in transferrin saturation (r = 0.3, P = 0.03) and hematocrit (r = 0.3, P = 0.05) were positively associated with change in anger/hostility.
Effect
Harmful
Effect size
Small
Dose
once a day for 8 weeks
Iron→Increased Hemoglobin Levels
changes in transferrin saturation (r = 0.4, P < 0.01) and hemoglobin (r = 0.3, P = 0.04) and hematocrit (r = 0.3, P = 0.03) were positively associated with changes in prospective food consumption
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Increased Prospective Food Consumption
changes in transferrin saturation (r = 0.4, P < 0.01) and hemoglobin (r = 0.3, P = 0.04) and hematocrit (r = 0.3, P = 0.03) were positively associated with changes in prospective food consumption
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Reduced Appetite
Hunger and desire to eat decreased, and fullness and composite satiety score increased after the meal (P-time < 0.0001 for all).
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Reduced Hematocrit
changes in transferrin saturation (r = 0.4, P < 0.01) and hemoglobin (r = 0.3, P = 0.04) and hematocrit (r = 0.3, P = 0.03) were positively associated with changes in prospective food consumption
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Reduced Hunger
Hunger and desire to eat decreased, and fullness and composite satiety score increased after the meal (P-time < 0.0001 for all).
Effect
Beneficial
Effect size
Small
Dose
once a day for 8 weeks
Iron→Reduced Satiety
changes in transferrin saturation were negatively associated with satiety (r = -0.3, P = 0.02)
Effect
Neutral
Effect size
Small
Dose
once a day for 8 weeks