How alfalfa sprouts cause autoimmunity
A long line of intriguing research in humans, primates and rodents4-33 demonstrates that alfalfa sprouts, seeds and supplements may cause an autoimmune disease known as systemic lupus erythematosus (SLE), particularly when consumed in excessive quantity. The classical explanation is that alfalfa contains an amino acid called L-canavanine which is thought to cause SLE via dysregulation of T and B lymphocytes in the immune system.6, 13, 14, 16, 18, 19, 30, 31, 33
However, this explanation may not fully explain why alfalfa sprouts, seeds and supplements cause autoimmunity.20 With the increasing realization that a leaky gut represents a fundamental environmental factor that underlies autoimmunity,1-3 then any food which has the potential to increase intestinal permeability may be suspect in autoimmune diseases.
Below is a table showing the saponin content of various foods. Note alfalfa sprouts tops the list.
One of the few raw legumes that we eat in the typical western diet are alfalfa sprouts. In vegetarian diets, they are standards in meatless sandwiches and vegetable salads. Alfalfa sprouts, seeds and supplements are potent sources of saponins23-28 which increase intestinal permeability. Most people eat alfalfa sprouts irregularly, so the potential adverse health effects of sporadic alfalfa consumption are probably of minor consequence, except for people suffering from autoimmune disease.
As a contemporary Paleo dieter, we should learn from the wisdom of our ancestral diet: a diet that rarely or never consisted of legumes.
Cordially,
Loren Cordain, Ph.D., Professor Emeritus
References
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