Luteolin.
A closer look at
immune signaling.

Population and design: 185 adults with persistent post-COVID smell impairment; 130 intervention, 55 control. Randomized, participant- and assessor-blinded study, with limitations in allocation and assessment schedules.

Dose and duration: 700 mg PEA + 70 mg luteolin, co-ultramicronized, once daily for 90 days. Both groups performed structured olfactory training.

Results: 120/130 active-group participants versus 23/55 controls had any TDI score increase. Nine active participants worsened and one was unchanged. Between-group endpoint TDI scores favored the combination (p<0.00001).

What remains uncertain: The effect of luteolin alone, the role of PEA and training, durability beyond 90 days and results with different delivery systems. No inflammatory biomarkers were measured. No adverse effects were identified.

Source details: Full text verified. Control baseline TDI is inconsistent between Table 1 (18.3) and results prose (18.2), so no calculated mean-change graph uses it.

Population and design: 250 recruited; 202 completed all three follow-ups and were analyzed. Four arms: training plus control, once-daily blend, twice-daily blend, and once-daily blend plus training. Attrition was 19.2% and differed between arms.

Dose and duration: Each sachet contained 700 mg PEA + 70 mg luteolin. Once or twice daily for 90 days, depending on arm. This study used the identification subtest, not the full TDI battery.

Results: Reported mean identification scores at baseline and day 90: control + training 6.5 to 9.0; once-daily blend 9.1 to 12.0; twice-daily blend 9.6 to 12.1; blend + training 8.2 to 12.8. Baseline differences complicate raw comparisons.

Numerical limitation: The text reports 76 combined-arm completers, but its responder statement gives 50 people and 89.2%, consistent with a different denominator. The combined-arm demographic table also differs from the narrative. This unresolved reporting inconsistency prevents a reliable responder chart.

Interpretation: This supports further study of the specific combination with training, not isolated luteolin. Participants could not be blinded to doing training. No adverse events were reported among study completers.

Population and design: Ten male Gulf War veterans contributed to the luteolin primary symptom analysis. Twenty-one men were analyzed across the report’s separate botanical experiments; eleven contributed luteolin pain/fatigue outcomes.

Dose and duration: One month baseline, one month placebo, one month 200 mg/day, then one month 400 mg/day. Luteolin was split between morning and evening doses. Lower dose always preceded higher dose.

Results: Mean 0–100 symptom severity: baseline 31.2, placebo 25.3, low dose 26.0, high dose 24.6. Neither low dose (p=0.718) nor high dose (p=0.492) was significantly better than placebo. Pain and fatigue also did not improve over placebo.

Limits: Small screening study, fixed phase order, possible carryover and a nonvalidated single-item symptom measure. It does not rule out all other uses, but it is direct evidence against assuming broad symptom relief at these doses.

Safety: Mild-to-moderate events occurred in the broader study. Luteolin phases included reports of diarrhea, reflux and flushing. Small numbers prevent precise adverse-event rates.

Population and design: Five men with low- or intermediate-risk prostate cancer under active surveillance. Single-arm phase I study with safety as the primary endpoint.

Dose and duration: 50 mg oral luteolin daily for 180 days. Blood tests and safety assessments at one, three and six months; repeat prostate biopsy after treatment.

Results: Two men had a negative repeat biopsy, one had stable findings and two had disease progression followed by surgery. PSA and PSA density did not change significantly. No symptomatic adverse events were found.

Interpretation: A negative biopsy does not prove a tumor was eliminated, and no untreated comparator was included. This is not evidence to use luteolin to treat cancer or replace active surveillance. Five people cannot establish general or long-term safety.

Source detail: Full text verified. Abstract and Table 1 disagree on some baseline age and PSA summaries; those disputed values are not used here.

Population and design: 50 children aged 4–10 with autism enrolled; 40 completed a 26-week open-label study. Assessments at baseline, week 18 and week 26.

Formulation and dose: Each oil-based capsule contained luteolin 100 mg, quercetin 70 mg and rutin 30 mg. One capsule per 10 kg body weight per day. This is a study exposure, not a pediatric dosing recommendation.

Results: Reported gains in Vineland age-equivalent scores: communication 8.43 months, daily living 7.17 months and social domain 8 months (p<0.005). These are test-score equivalents, not a claim that development accelerated by those amounts.

Limits and safety: Maturation, concurrent support, expectations and dropout can contribute to change without placebo control. Transient increased irritability occurred in 27/50 children for 1–8 weeks. Findings cannot be assigned to luteolin alone or used to recommend unsupervised supplementation in children.

Source access: Primary abstract verified. A later cytokine report from this trial is not counted as an independent efficacy study.