Good Nutrition Nutrition and Nutrients

Nutrition Notes

Peptides Derived From Food Proteins

Pieces of milk and wheat proteins (peptides) that mimic the body's endorphins were described by Zioudro, Streaty and Klee as "exorphins" in 1979. Hydrolyzed wheat gluten, for example, was found to prolong intestinal transit time and this effect was reversed by concomitant administration of naloxone, a narcotic-blocking drug. Digests of milk proteins are also opioid peptides. Deficiencies in the bowel production of regulatory addictive peptides, such as endorphins, would likely be associated with cravings and compulsions to increase food ingestion.

There are gut-regulatory peptides feeding back to brain control centers to form the brain-gut axis. The information flow between the gut and brain is critical in regulating eating behaviors and weight control. Milk and wheat proteins yield active peptides, substances may be numerous in the digestive tract after a meal. The absorption of larger peptides may be irregular, with variable symptom production after meals, making the interpretation of milk and wheat disease difficult. Other foods are likely to yield similar peptides.

A 29 year old pharmacist wrote to me: “When I drink milk or any dairy products I get dizzy, have loss of concentration, reduced memory recall and excessive drowsiness with prolonged deep sleep. I am not experiencing any digestive disturbance. I tried lactaid and it didn't work as my problem is with the CNS not with the GI Tract. The symptoms started as a child and whenever I drank milk I would become dizzy and sleepy with loss of concentration. At nineteen I began drinking milk in larger quantities and realized that it was affecting my concentration and my studies in school. When I stopped the intake of milk, I found an improvement in memory and concentration.”

From our basic understanding of protein digestion, we should predict that there will be regular traffic of peptide information passing from food digests into the body. Ingestion of normal food may result in information-molecules streaming into our bloodstream from stomach or small intestine with all the impact of narcotic drugs.

A "Gluten Stimulatory Peptide" was described with narcotic (opiate) antagonist properties. It has been suggested that gluten hydrolysates, digests of wheat protein, have mixed opiate agonist-antagonist activity and, like two drugs with mixed narcotic activating and blocking actions (nalorphine and cyclazocine), produce dysphoria and even psychotic symptoms. Loukas and colleagues have derived the structure of cow's milk-derived exorphins. The following two peptides carry information by finding and binding to brain receptors which ordinarily respond to endorphins. The message is go to sleep, feel bad, but go back for more.

Arg-Tyr-Leu-Gly-Tyr-Leu-Glu (digested from alpha casein)

Tyr-Pro-Phe-Pro-Gly (digested from beta casein)

Dohan’s theory that gluten-derived peptides cause schizophrenia has been advanced by several researchers.

Reichelt et al isolated bovine casomorphin 1-8 immunoreactive peptides from the urine and dialysis fluid of schizophrenics and autistics.
Casomorphin accumulates in the blood, spinal fluid and urine in post-partum psychosis.

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