(P31-24-26) High-Dose Strawberry Consumption Reduces Inflammatory Biomarkers and Increases Serum Iron in Women With Obesity: A Crossover Study

Objectives: To evaluate the acute and short-term effects of high-dose strawberry intake on inflammatory signaling and iron biomarkers in reproductive-aged women with obesity.

Methods: In a two-period crossover study, 15 women with obesity (19–45 y) consumed a low-dose beverage (24 g freeze-dried strawberry [FDS] powder/day) for 1 week, followed by a 2-week washout, then a high-dose beverage (72 g FDS powder/day) for 1 week. This abstract reports the high-dose phase. Fasting blood samples were collected 2 h pre- and post-intake on Day 1 and Day 7 of each period. Acute effects were assessed by within-day comparisons; short-term effects by Day 1 vs. Day 7 pre-intake values. Inflammatory biomarkers included interleukins (IL-6, IL-8, IL-18), tumor necrosis factor-alpha (TNF-α), C-reactive protein (CRP), serum amyloid A (SAA), and soluble TNF receptors (sTNFRI, sTNFRII). Iron markers included serum iron, ferritin, soluble transferrin receptor (sTfR), and percent transferrin saturation (%TS). Paired t-tests were conducted on log-transformed data.

Results: Day 7 acute reductions were observed for IL-8, TNF-α, sTNFRI, and sTNFRII (geometric means [95% CI]): IL-8 3.17 [2.74–3.65] vs. 2.81 [2.44–3.22], P=0.007; TNF-α 0.86 [0.58–1.29] vs. 0.79 [0.52–1.20], P=0.044; sTNFRI 94.5 [78.9–113.3] vs. 67.3 [48.3–93.7], P=0.040; sTNFRII 1.24 [1.14–1.34] vs. 1.13 [1.02–1.25], P< 0.001 (all pg/mL). On Day 1, only IL-18 changed acutely (468.5 [384.0–571.5] vs. 504.6 [412.1–617.9], P=0.008). CRP, SAA, and IL-6 did not differ at any timepoint. Serum iron (µg/dL) increased on both days (Day 1: 77.7 [65.1–92.7] vs. 89.9 [74.7–108.3], P=0.013; Day 7: 70.8 [53.3–94.2] vs. 82.7 [62.8–108.9], P=0.007). Acute increases in sTfR occurred on Day 1 (18.2 [15.9–20.9] vs. 18.8 [16.4–21.7], P=0.003) and in %TS on Day 7 (18.9 [14.0–25.4] vs. 21.6 [15.6–29.8], P=0.02). Ferritin, sTfR, and %TS showed no short-term differences.

Conclusions: Findings suggest that high-dose strawberry beverage consumption may elicit acute anti-inflammatory responses after 7 days of exposure and acutely increased serum iron, highlighting potential roles for strawberry-derived bioactives in modulating inflammation and iron status in women with obesity. Further analyses will compare the effects of high and low doses.

Funding Sources: Internal funding from the School of Public Health at Indiana University Bloomington