By Kelley Herring
Autoimmune disease has become an epidemic, with some conditions three to five times more common today than just a few decades ago. And while, there is still much to learn about this growing health threat, we do know that most cases of autoimmunity develop as a result of three key factors:
- Genetic predisposition
- Environmental trigger and
- Leaky gut.
This “autoimmune triad” is widely accepted in the functional medicine community. However, we have only recently begun to understand the specific triggers and genetics that put you at risk.
In today’s article, we explore a group of genes (HLA-B27), which are associated with autoimmune disease… and how these genes are impacted by starch in the diet. We also reveal why a low-starch diet may ease symptoms or even help to “reverse” autoimmunity.
What is HLA-B27?
You probably already know that your genetics provide robust information about your personal risk factors for disease.
Human leukocyte antigen, or HLA, is a set of genes related to your immune system. “Leukocytes” are white blood cells, and “antigens” are proteins on the surface of cells. In essence, HLA tells your body which proteins should be present on the surface of your immune cells.
HLA is polymorphic gene – or a gene with many “faces”. This means there can be many possible variations (known as haplotypes) of the same gene. One of these haplotypes is HLA-B27.
While relatively uncommon, HLA-B27 impacts about eight percent of Caucasians, nine percent of Chinese, four percent of North Africans, and less than one percent of Japanese.i
Several autoimmune diseases have been associated with HLA-B27. The most common of these is ankylosing spondylitis (AS). Chrohn’s disease, inflammatory bowel disease, ulcerative colitis, uveitis and rheumatoid arthritis are also associated.iiiii
Molecular Mimicry: When the Immune System Misfires
Your immune system has an amazing “memory” – with the ability to recognize pathogens it encountered decades ago. Your immune system is also highly specific when selecting compounds to attack and neutralize. However, it’s not perfect. And sometimes it can confuse one thing for another.
For example, proteins in coffee beans, milk, oats, corn, rice and other foods may “appear” similar to gluten.iv This is because they contain a short, specific amino acid sequence that is also found in gluten.
In those sensitive to gluten, this similarity can trigger the immune system to register the food as an invader and mount an attack. When the immune system confuses one food for another, this is called cross-reactivity.
But this immunologic confusion doesn’t just happen with foods…
It can also happen with bacteria and other protein-containing substances. For example, Proteus bacteria have an amino acid sequence that resembles type-6 collagen. This is why people with the HLA-DR1/4 haplotype who have been infected with Proteus often develop rheumatoid arthritis – a debilitating condition where the immune system attacks the joints and other parts of the body where collagen is present.v
When your body confuses your own tissues with an invader and mounts an immune attack, this is called molecular mimicry.
Similarly, Klebsiella bacteria have molecular sequences that resemble HLA-B27.vi In this scenario, the immune system produces antibodies against Klebsiella to clear it from the body. But thanks to molecular mimicry, these antibodies may also inadvertently bind to HLA-B27.
And that’s exactly what researchers have found happens with ankylosing spondylitis (AS)!
In fact, stool samples show that people with AS have a greater abundance of Klebsiella bacteria than those without AS.vii What’s more, these patients also had higher levels of anti-Klebsiella antibodies in their blood.viii
How a Low Starch Diet Can Help Autoimmunity
As you know, the foods you eat impact your microbiome – the collective set of organisms in and on your body. And as you’ve just discovered, it can sometimes be the bacteria which reside in our body that can trigger the immune system to attack our own cells.
Gram-negative Klebsiella thrive on starch and as more starch is available in the diet, these bacteria rapidly multiply.ix In fact, a randomized control trial (RCT) – the gold standard for scientific studies – compared the Klebsiella levels in people divided into two dietary groups:
A low-starch diet was also found to reduced total serum IgA in AS patients, indicating lower immune activity and autoimmune attack.xii What’s more, most of these patients also reported an improvement in symptoms and, in some cases, full remission.
Is a Low Starch Diet Right for You?
While a blood test is the only 100 percent accurate way to determine if you have HLA-B27 genetic variant, you can find out your likelihood with your 23andMe (v5) or Ancestry DNA by looking at rs4349859:
A/G: high likelihood of carrying 1 copy of HLA-B27
Foods with high levels of starch include peas, corn, potatoes, beans, rice, bananas, plantains, prunes, raisins and figs. And of course, any made with grains, including bread, pasta, cereal and other processed baked goods.
Low-Starch Diet: Meal Plan Ideas
If you’re interested to try a low starch diet, here are some quick and delicious meal ideas to get you started:
Pastured Eggs and Sugar-Free Bacon
Sugar-Free Breakfast Sausage and Avocado
Grass-Fed Burgers in Butterhead Lettuce Wraps with Avocado Mayo
Bison Steak with Arugula Salad
Garlicky Shrimp Scampi with Zoodles and Olives
Pastured Pork Chops with Braised Red Cabbage and Fennel
Do you suffer from autoimmune disease? If so, have you tried a low-starch diet? What was your experience?
Read more of Kelley Herring’s health & wellness articles on our Discover Blog.
Kelley Herring is the author of the brand new book Keto Breads – which includes more information you need to know about why it is so important to avoid wheat and grains in your diet, plus how to use healthy replacements for these foods to create all the breads you love… without the gluten, carbs and health-harming effects. Click here to learn more about Keto Breads…
Sources & References
i Khan MA.HLA-B27 and its subtypes in world populations.Curr Opin Rheumatol. 1995 Jul;7(4):263-9.
ii Sheehan NJ. The ramifications of HLA-B27. J R Soc Med. 2004;97(1):10–14. doi:10.1258/jrsm.97.1.10
iii Lin P, Bach M, Asquith M, et al. HLA-B27 and human β2-microglobulin affect the gut microbiota of transgenic rats. PLoS One. 2014;9(8):e105684. Published 2014 Aug 20. doi:10.1371/journal.pone.0105684
iv Vojdani A, Kharrazian D, Mukherjee PS. The prevalence of antibodies against wheat and milk proteins in blood donors and their contribution to neuroimmune reactivities. Nutrients. 2013;6(1):15–36. Published 2013 Dec 19. doi:10.3390/nu6010015
v Ebringer A1, Rashid T.Rheumatoid arthritis is caused by Proteus: the molecular mimicry theory and Karl Popper.Front Biosci (Elite Ed). 2009 Jun 1;1:577-86.
vi Schwimmbeck PL, Yu DT, Oldstone MB. Autoantibodies to HLA B27 in the sera of HLA B27 patients with ankylosing spondylitis and Reiter’s syndrome. Molecular mimicry with Klebsiella pneumoniae as potential mechanism of autoimmune disease. J Exp Med. 1987;166(1):173–181. doi:10.1084/jem.166.1.173
vii Cowling P, Ebringer R, Cawdell D, Ishii M, Ebringer A.C-reactive protein, ESR, and klebsiella in ankylosing spondylitis.Ann Rheum Dis. 1980 Feb;39(1):45-9.
viii Ebringer A1, Cox NL, Abuljadayel I, Ghuloom M, Khalafpour S, Ptaszynska T, Shodjai-Moradi F, Wilson C.Klebsiella antibodies in ankylosing spondylitis and Proteus antibodies in rheumatoid arthritis.Br J Rheumatol. 1988;27 Suppl 2:72-85.
ix Pugsley AP, Chapon C, Schwartz M. Extracellular pullulanase of Klebsiella pneumoniae is a lipoprotein. J Bacteriol. 1986;166(3):1083–1088. doi:10.1128/jb.166.3.1083-1088.1986
x Martin RM, Bachman MA. Colonization, Infection, and the Accessory Genome of Klebsiella pneumoniae. Front Cell Infect Microbiol. 2018;8:4. Published 2018 Jan 22. doi:10.3389/fcimb.2018.00004
xi Ebringer A1, Wilson C.The use of a low starch diet in the treatment of patients suffering from ankylosing spondylitis.Clin Rheumatol. 1996 Jan;15 Suppl 1:62-66.
xii Ebringer A1, Wilson C.The use of a low starch diet in the treatment of patients suffering from ankylosing spondylitis.Clin Rheumatol. 1996 Jan;15 Suppl 1:62-66.
xiii Evans DM, Spencer CC, Pointon JJ, et al. Interaction between ERAP1 and HLA-B27 in ankylosing spondylitis implicates peptide handling in the mechanism for HLA-B27 in disease susceptibility [published correction appears in Nat Genet. 2011 Sep;43(9):919. Opperman, Udo [corrected to Oppermann, Udo]; Moutsianis, Loukas [corrected to Moutsianas, Loukas]]. Nat Genet. 2011;43(8):761–767. Published 2011 Jul 10. doi:10.1038/ng.873