WDDTY loves nothing more than a bandwagon, and if one bogus treatment won’t do there’s bound to be another along any minute.
If your vitamin levels check out but you are still depressed, think twice about dairy and wheat. Nutritionists have discovered morphine-like substances called ‘exorphins’ -derived from the incomplete digestion of proteins in cereal grains and dairy products-which may be a possible cause of depression.
Stop right there. Nutritionists have discovered nothing, other than how to fleece the credulous.
Scientists and dieticians, however, have indeed discovered this, but the devil is in the detail, as we shall see in a moment.
The evidence reveals five distinct exorphins in the pepsin digests of gluten, and eight other exorphins in the pepsin digests of milk.
J Biol Chem, 1979; 254: 2446-9, cutting edge research form the bottom of WDDTY’s clipping drawer there.
Peptides with opioid activity are found in pepsin hydrolysates of wheat gluten and alpha-casein. The opioid activity of these peptides was demonstrated by use of the following bioassays: 1) naloxone-reversible inhibition of adenylate cyclase in homogenates of neuroblastoma X-glioma hybrid cells; 2) naloxone-reversible inhibition of electrically stimulated contractions of the mouse vas deferens; 3) displacement of [3H]dihydromorphine and [3H-Tyr, dAla2]met-enkephalin amide from rat brain membranes. Substances which stimulate adenylate cyclase and increase the contractions of the mouse vas deferens but do not bind to opiate receptors are also isolated from gluten hydrolysates. It is suggested that peptides derived from some food proteins may be of physiological importance.
This paper is by now mainly quoted in the alternative journals, it seems, but the finding is unsurprising.
These foods can also inhibit the takeup of nutrients like B12. Exorphins act like depressants, and it’s now thought that the immune reactions that arise from eating these foods include a number of psychiatric symptoms, even simple ‘brain fog’.
Well done, linking both stories to try to provide support for the Brave Maverick Doctor, Joseph Chandy.
Depression has also been linked to allergies and coeliac disease, where the inner lining of the small intestine (the mucosa) is damaged after eating gluten-containing grains like wheat, rye, oats and barley.”‘ According to a recent review, as many one-third of adult coeliacs suffers from various vitamin deficiencies and neurological changes, including depression.
AmJ Gastroenterol, 1999; 94: 839–43:
Untreated celiac disease can lead to serious behavioral disorders. We describe three adult patients with undiagnosed or untreated celiac disease without particular intestinal signs, causing persistent depressive symptoms in three of the parents of our pediatric patients.
See the important bit? These are coeliac patients.
lranJ Neurol,2012; 11: 59–64:
Celiac disease or gluten sensitivity may initially present as one or more neurological signs and/or symptoms. On the other hand, it may be associated with or complicated by neurological manifestations. Neurological presentations are rare in children but as many as 36% of adult patients present with neurological changes. With severe malnutrition after progression of celiac disease, different vitamin deficiencies may develop. Such problems can in turn overlap with previous neurological abnormalities including ataxia, epilepsy, neuropathy, dementia, and cognitive disorders. In this study, we aimed to review the neurological aspects of celiac disease. Early diagnosis and treatment could prevent related disability in patients with celiac disease.
So, not only does this undermine your proposed causal link between vitamin B12 and depression (vitamin deficiencies are very common in coeliac patients due to malabsorption), but they fail to establish any link outside of coeliac disease.
The correct advice is not to arbitrarily cut out gluten, but to see your doctor and find out if you an undiagnosed coeliac. Adult diagnosis is now very common and estimates range from under half a percent to around one percent of the population. Get a TTGA test, not a quack diet, because non-coeliac gluten sensitivity may well not exist.