Tuesday, January 12, 2010

Paleo Diet Q & A - 12 January 2010

Dear Readers,

Here's today's edition of Paleo Diet Q & A.

Q: Have you had any results in curbing the symptoms of Crohn's Disease with the Paleo Diet. As I am a sufferer, I would love to know.

Thank you,

A: Dear Shannon,

Indeed, inflammatory bowel disease (Ulcerative Colitis & Crohn's Disease) patients usually do very well with The Paleo Diet, as nutrients are one of the main environmental triggers of this condition.

Crohn's disease is an autoimmune disease where the immune system mounts an attack against its own tissues, in this case the cells lining the intestine.

For an autoimmune disease to occur we need a genetic predisposition and an environmental trigger. The genetic predisposition depends on genes coding for the HLA system. On the other side, one of the environmental triggers may be nutrition, besides infections, geography (vitamin D deficiency), physical trauma or vaccination.

One of the key points in this process is increased intestinal permeability. This means that the gut barrier allows increased passage of bacterial or food proteins (antigens) into peripheral circulation, skipping a process known as oral tolerance. Once antigens get in contact with the immune system located in the gut associated lymphoid tissue, they may elicit a T-cell mediated immune response against those antigens.

If the molecular structure of the dietary or bacterial antigens is similar to that of the HLA system (part of the immune system presenting cells machinery), chances are that a cross reaction between foreign antigens and self antigens (produced by T-cells) occur. This is termed molecular mimicry and leads to self injury by the adaptive immune system.

Hence, decreasing intestinal permeability is one of the treatment targets. There are several nutrients known to increase intestinal permeability that you may want to avoid, at least until symptoms subside. Here you have a list of them and the noxious substance in parentheses:

  • Cereal grains (lectins and gliadin)
  • Legumes, including soya and peanuts (lectins and saponins)
  • Tomato (tomato lectin and alpha-tomatin)
  • Potato (lectins and saponins)
  • Chili (capsaicin)
  • Quillaja (foaming substance)
  • Quinoa (saponins)
  • Egg white (lisozyme)
  • Alfalfa sprouts (saponins)
  • Amaranth (saponins)
  • Alcohol
Moreover, some nutrients exert an adjuvant-like activity (they stimulate the immune system), which is something you don't want to if you are suffering from an autoimmune disease. Nutrients containing adjuvants:
  • Quillaja extract, found in root beer
  • Tomato alpha-tomatine
Dairy products and vegetable oils also have deleterious effects upon your immune system.

I hope this helps.

Q: Good Morning,

I've recently started on the Paleo Diet. I've read through your site and others to make sure I'm going about it the right way. What a revelation! It's fantastic in its simplicity.

My concern is that when I was about 18 I developed an allergy to fish. I have no idea how this happened. I ate two or three nights a week growing up at home. Curiously, this allergy seems to only apply to scaled fish, as I can still eat shellfish. I am 23 years old.

When I eat fish I get terrible heartburn/indigestion, and the last time I tried it, about two years ago, my face started swelling and itching. I saw an allergist who told me to avoid fish because of the potential of a very serious reaction.

What do you recommend I do? It seems like eating seafood is a big part of the Paleo Diet. I'm happy to eat shellfish, but aside from shrimp it's often prohibitively expensive. Obviously I'm not going to eat fish unless I can "outgrow" the allergy. I was once allergic to eggs, but I've gotten over that now.


A: Dear Harrison,

From an evolutionary standpoint fish allergy is nonsense, as it has been part of the human nutrition since, probably, 2-2.5 million years ago.

Allergy is an exaggerated reaction of the body's immune system against foreign proteins, where the body's common mucosal immune system (located in the gut, nose, eyes, lungs, etc) increases the production of cell (eosinophils) and/or antibody (IgE) mediated immune response. This leads to histamine release throughout the CMIS and signs and symptoms related to allergy, such as inflammation, redness, itching, sneezing, or anaphylactic shock if acute vasodilatation occurs.

But how or why do fish proteins trigger an allergy reaction?
  1. An early exposure to food proteins, lets say before 3-6 months of life, when the gut associated lymphoid tissue is immature increases the risk of allergy later in life.

  2. An increased intestinal permeability allows food proteins to pass through the gut barrier and skip M-cells mediated oral tolerance, inducing hyper-sensitivity to those proteins.

  3. In the last years a wide body of scientific papers has shed light to what is known as the "hygiene hypothesis". A correlative association has been shown between increased use of antibiotics and vaccines and inflammatory conditions such as multiple sclerosis, type 1 diabetes and allergy, during the last 50 years. Human beings are less exposed to microorganisms, such as intestinal bacteria, than they used to. This leads to lack of immune regulation mediated, in part, by gut and environmental microorganisms.
How can the Paleo Diet help you?

Of course we can not address point 1 but we can do something regarding points 2 and 3.

The Paleo Diet is free of some food known to increase intestinal permeability such as cereal grains, legumes (soya and peanuts), alcohol, tomato, potato, quinoa, amaranth, egg white, alfalfa sprouts and root beer (quillaja extract). By eliminating those foods and eating a diet based on lean meats, shellfish, vegetables, fruits and nuts your intestinal permeability will decrease and your immune system will be less challenged by those food proteins (fish) and perhaps we can restore immune tolerance to a normal food as fish. For more information about intestinal permeability and nutrition we recommend you to check out our published newsletters section.

Regarding point 3 we suggest you to take a probiotic supplement (6-9 billion/day) for several months.

Other supplements that can help you improve intestinal permeability:
  • Pre-biotic 2-4grs/day
  • L-glutamine 0.2grs/kg body weight one month, then 0.1gr/kg
  • Zinc 25mg/day
  • Vitamin D 2000 IU
  • Omega-3 fatty acids EPA+DHA=2.6grs/day
I hope this is useful.


  1. Posted on behalf of Harrison:


    Thank you so much for this information! This is very useful. Indeed, I think I'll stick to this diet for a few months and then try fish again, with some antihistamine and an epinephrine nearby, just in case. You guys are doing a good thing. Keep up the good fight!


  2. When Dr. Cordain calculates, for the hunter-gatherers diet, an animal to plant foods ratio of 65:35, what these figures refer to: weight, volume, calories?

    Also, what is his current advice regarding the number and timing of daily meals? I ask this because I've recently read Ori Hofmekler's The Warrior Diet suggesting only one daily meal at evening, and recalled having read something like this in The Paleo Diet Newsletter some time ago.

  3. When the Paleo diet was first published, it said that seafood was not consumed by Paleolithic hunter-gatherers.

    Do you now think that seafood was consumed during the Paleolithic era?

  4. Could you comment on alcohol and how it is a problem if one has auto-immune issues and vitamin B12 absorption. Is it possible to continue to have a little (like 4 oz wine a day) or should it be cut out altogether?


  5. Of course if someone just ate sugar red meat and milk they could still abuse this approach but it provides a good commonsense starting point for what is healthy and what isn't.


The Paleo Diet Team invites you to leave comments or post questions to our blog. We receive a great amount of feedback, but we are not able to always answer personally. We read all comments, and we are very interested in hearing your thoughts, learning about your experiences, and understanding what questions you have. Note that we review all comments before publishing them on the blog. Comments posted that do not contain questions or comments related to paleo nutrition, or those that point to web sites that do not provide content that would be deemed helpful to our readers, will be rejected.

Thank you.
The Paleo Diet Team