Effect of Fish Oil and Vitamin C on Exercise-Induced Bronchoconstriction and Airway Inflammation in Asthma

Comparative and Additive Effects of Fish Oil and Ascorbic Acid Supplementation on Exercise-Induced Bronchoconstriction and Airway Inflammation in Asthma

Status

Completed

Phases

Phase 1

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT01057615

Enrollment

Registered

2010-01-27

Start date

2010-03-31

Completion date

2010-12-31

Last updated

2011-01-31

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Asthma

Keywords

Asthma, Exercise-Induced Bronchoconstriction, Inflammation, Airway, Fish Oil, Ascorbic Acid

Brief summary

Combining fish oil and vitamin C supplementation will provide a greater anti-inflammatory effect against developing exercise-induced bronchoconstriction (EIB) than either nutritional supplement alone.

Detailed description

The aim of this study is to extend previous findings that nutritional supplementation or dietary modification can ameliorate exercise-induced bronchoconstriction. It has been shown in separate studies that fish oil and ascorbic acid (vitamin C) individually protect against EIB by improving pulmonary function and reducing airway inflammation. The main aim of this study is to determine the comparative and additive effects of fish oil and ascorbic acid supplementation on EIB and airway inflammation in asthmatic individuals.

Interventions

DIETARY_SUPPLEMENTFish Oil

10 fish oil (3.2g EPA + 2.0g DHA) capsules per day for 3 weeks

DIETARY_SUPPLEMENTAscorbic Acid

2 pharmaceutical grade ascorbic acid (1500mg) capsules per day for 3 weeks

DIETARY_SUPPLEMENTFish Oil Placebo

10 placebo fish oil (soy bean oil) capsules per day for 3 weeks

DIETARY_SUPPLEMENTAscorbic Acid Placebo

2 placebo ascorbic acid (sucrose) capsules per day for 3 weeks

Study design

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Masking

DOUBLE (Subject, Investigator)

Eligibility

Sex/Gender

ALL

Age

18 Years to 40 Years

Healthy volunteers

Inclusion criteria

* Diagnosis of asthma, based on medication use as well as history and symptoms as outlined in the NHLBI Guidelines for the Diagnosis and Management of Asthma * Diagnosis of EIB, based on ≥10% fall in post-challenge FEV1, a measure of lung function, after dry air eucapnic voluntary hyperventilation (EVH), a simulated exercise challenge * Not currently taking asthma maintenance medication or physician approval to discontinue current asthma medication for the duration of the study * Not currently taking any fish oil or ascorbic acid supplements above the level recommended for adequate intake (if currently taking supplements, can participate if the subject stops taking the supplements for 2 weeks before starting the study and throughout the study) * Agree to limit fish consumption to 1 fish meal per week throughout the study * Agree to avoid vitamin C-rich foods throughout the study

Exclusion criteria

* Resting FEV1 (the amount of air blown out in the first second of a forced exhalation) \<60% of predicted when off medication * Pregnancy * History of cardiovascular disease, including hyperlipidemia (high cholesterol) and hypertension (high blood pressure) * History of bleeding disorders or delayed clotting time * History of diabetes * History of seizures * Allergy to fish oil or ascorbic acid (vitamin C)

Design outcomes

Primary

Measure	Time frame
Pulmonary Function	8 weeks

Secondary

Measure	Time frame
Exhaled nitric oxide to measure airway inflammation	8 weeks

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026