Assessing the Presence of Casomorphins in Human Plasma After Dairy Ingestion
Study Details
Study Description
Brief Summary
This purpose of this study is to perform a pilot investigation to determine if opioid peptides such as casomorphin can be detected in human plasma after cheese ingestion.
| Condition or Disease | Intervention/Treatment | Phase |
|---|---|---|
|
Early Phase 1 |
Detailed Description
Cheese is one of the most commonly craved foods, suggesting the possibility of opiate activity, as has been demonstrated with other craved foods, particularly chocolate. Like other dairy products, cheese contains casein, which is the major protein in cow's milk. This is unlike human milk, in which the primary protein is whey. Casein includes αs1-, αs2-, β- , and κ-casein, with αs1 and β forms predominating. Human and bovine casein molecules are cleaved during digestion to release opioid peptides that are believed to have biological properties relevant to infant physiology and behavior. Specifically, β-casein is cleaved to form β-casomorphins. Like other opiate agonists, β-casomorphins prolong gastrointestinal transit time and have an antidiarrheal effect.
Casomorphin receptor binding has been demonstrated in opiate receptor assays and bioassays. Duodenal aspirates from human volunteers given cow's milk have demonstrated the presence of several casomorphins, particularly β-casomorphin-7. Few studies have assessed the presence or action of casomorphins in humans. The ability of casein-derived opioid peptides to pass into the bloodstream is not well characterized, and is the subject of the present study.
Study Design
Arms and Interventions
| Arm | Intervention/Treatment |
|---|---|
| Experimental: A Cheese |
Behavioral: cheese ingestion
On study day 1, approximately half of the participants will consume a breakfast of fruits and vegetables, whereas the other half of participants will consume a meal consisting of 9 oz. of cheese.
Blood samples will be collected from participants immediately prior to consumption of the meals, and then again at regular intervals for up to 8 hours following the meals.
At least 3 days later, participants will return for study Day 2. The participants will receive the second meal. Blood samples will then be collected immediately prior to consumption of the test meal and for up to 8 hours after the meal.
|
| Placebo Comparator: B Fruits and vegetables |
Behavioral: cheese ingestion
On study day 1, approximately half of the participants will consume a breakfast of fruits and vegetables, whereas the other half of participants will consume a meal consisting of 9 oz. of cheese.
Blood samples will be collected from participants immediately prior to consumption of the meals, and then again at regular intervals for up to 8 hours following the meals.
At least 3 days later, participants will return for study Day 2. The participants will receive the second meal. Blood samples will then be collected immediately prior to consumption of the test meal and for up to 8 hours after the meal.
|
Outcome Measures
Primary Outcome Measures
- casomorphin quantification [Measurements will be collected on designated studys within 12-hour time frame]
Eligibility Criteria
Criteria
Inclusion Criteria:
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Age greater than 18 years
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Male or female
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Either self-described as having a strong liking for cheese, or have been following a vegan diet for a least the previous six months.
Exclusion Criteria:
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Unstable medical status
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Physical condition affecting eating behavior, digestion, or intestinal absorption
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Dairy allergy or lactose intolerance
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Pregnancy
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History of severe mental illness
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Smoking during the past six months
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Alcohol consumption of more than two drinks per day
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History of substance abuse or dependency followed by any current use
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Inordinate fear of blood draws
Contacts and Locations
Locations
| Site | City | State | Country | Postal Code | |
|---|---|---|---|---|---|
| 1 | Physicians Committee for Responsible Medicine | Washington, DC | District of Columbia | United States | 20016-4131 |
Sponsors and Collaborators
- Physicians Committee for Responsible Medicine
Investigators
- Principal Investigator: Neal Barnard, MD, Physicians Committee for Responsible Medicine
- Study Director: Hope R Ferdowsian, MD, MPH, Washington Center for Clinical Research
Study Documents (Full-Text)
None provided.More Information
Additional Information:
Publications
- Brantl V, Teschemacher H, Bläsig J, Henschen A, Lottspeich F. Opioid activities of beta-casomorphins. Life Sci. 1981 Apr 27;28(17):1903-9.
- Drewnowski A, Krahn DD, Demitrack MA, Nairn K, Gosnell BA. Taste responses and preferences for sweet high-fat foods: evidence for opioid involvement. Physiol Behav. 1992 Feb;51(2):371-9.
- Meisel H, FitzGerald RJ. Opioid peptides encrypted in intact milk protein sequences. Br J Nutr. 2000 Nov;84 Suppl 1:S27-31. Review.
- Shah NP. Effects of milk-derived bioactives: an overview. Br J Nutr. 2000 Nov;84 Suppl 1:S3-10. Review.
- Svedberg J, de Haas J, Leimenstoll G, Paul F, Teschemacher H. Demonstration of beta-casomorphin immunoreactive materials in in vitro digests of bovine milk and in small intestine contents after bovine milk ingestion in adult humans. Peptides. 1985 Sep-Oct;6(5):825-30.
- WCCR-01