We’ve lately been having a lot of discussions about the hypothalamic/pituitary hormone, oxytocin, that, when boosted by consuming our L. reuteri yogurt, yields potent age-reversing and other health effects. Let’s now discuss another hormone that, while also originating in the pituitary, plays an entirely different role: prolactin.
Just as its name suggests, prolactin is the pituitary hormone that prepares the human breast for lactation, i.e., milk production to nourish an infant during breastfeeding. In other words, many of the effects of prolactin are unique to the breastfeeding period, a crucial phenomenon in successfully raising a child. (Human breast milk and breastfeeding are fascinating and critical for the infant that yields, for instance, probiotic microbes, prebiotic fibers, hormones, and other factors that shape the development and lifelong health and behavior of the child.) Outside of the breastfeeding period, humans—both women and men—are meant to have low circulating levels of this hormone.
Funny thing: The gliadin protein of wheat and related grains, upon the partial digestion that humans are capable of (given our inability to fully digest this protein), yields a protein fragment, or peptide, called the B5 pentapeptide, i.e, a peptide that is five amino acids in length. The B5 pentapeptide has the unique ability to provoke release of prolactin that, yes, is one of the reasons why people—men and women—have larger breasts when they habitually consume wheat and related grains, what I have labeled the “Dolly Parton Effect.” While these wheat/grain effects apply to everyone, regardless of whether or not celiac disease is present, we know that children with celiac disease commonly experience up to 500% higher levels of prolactin compared to kids without celiac disease, a phenomenon that normalizes within several months of banishing all gluten-containing sources in the diet. (This B5 pentapeptide effect is blocked by administration of the opiate-blocking drug, naloxone, consistent with the B5 pentapeptides opioid characteristics.)
A few fun facts about prolactin:
- People with type 2 diabetes have 350% higher blood levels of prolactin
- Higher prolactin levels contribute to numerous autoimmune diseases including systemic sclerosis, multiple sclerosis, Hashimoto’s thyroiditis, anti-phospholipid antibody syndrome and others. The higher levels of prolactin in females explains why women are more prone to autoimmune diseases than males.
- Sustained higher levels of prolactin lead to osteoporosis due to increased bone “turnover” consistent with prolactin’s role in mobilizing calcium from bone to produce breast milk
- Higher prolactin levels may be associated with cognitive impairment
- Higher prolactin levels play a role in psychotic illness
I believe that you can begin to appreciate that, outside of breastfeeding period, having abnormally high levels of prolactin is probably not a good thing.
The hormonal disruptions of wheat/grain consumption are further magnified by the accumulation of visceral abdominal fat that, among its broad collection of adverse health effects, is also associated with increased activity of the aromatase enzyme that converts testosterone to estrogen in males, increases estrogen in females. In women, the increase in aromatase activity occurs in both visceral fat as well as breast tissue, a situation that increases potential for breast cancer. And being overweight or obese further increases prolactin blood levels.
By following the Wheat Belly lifestyle, people remove the source of the B5 pentapeptide and other exorphins (gliadin-derived opioid peptides) while also enjoying dramatic reduction in visceral fat. As a result, prolactin levels decline, abnormally high estrogen levels drop, testosterone levels in men go up. Among the results: a reduction in breast size in both men and women. Some women lament the loss of breast size, but bear in mind that abnormal breast tissue stimulation by estrogens increases risk for breast cancer; reducing such abnormal breast tissue stimulation is a healthy effect that is protective.
Truly healthy foods should not exert hormonally disruptive effects. These are among the perverse effects of trying to make something that was unsuited as human food—the seeds of grasses, “grains”—into food, regardless of whether it is organic, sprouted, fair-trade, or endorsed by the USDA or Academy of Nutrition and Dietetics.