Scientific Articles


On this page you will find some scientific articles written by our doctors.  If they are published the journal will be cited. Some articles are a little more sophisticated in their language than what we include in our typical blog posts and are therefore included here as well.


Can We Finally Stop Arguing About the Existence of Gluten Sensitivity? Yes!

The argument over the existence of gluten sensitivity as a legitimate condition was finally laid to rest recently in a landmark opinion article published February 2012 in BioMed Central. Titled “Spectrum of gluten-related disorders: consensus on new nomenclature and classification”, the authors make up a veritable ‘who’s who’ of the most respected doctors in the gluten research world.

The team of fifteen came together October 2011 in London to hash out a consensus of nomenclature and create a paradigm for treatment as it concerned the three major varieties of gluten intolerance: wheat allergy, celiac disease and gluten sensitivity.

It has never been argued that true wheat allergies exist, and a test that’s accurate for the diagnosis has been around for a long time – namely an IgE blood test and skin scratch test.

Similarly, celiac disease has also never been refuted as a disease, but the criteria for a positive diagnosis has been the subject of hot debate of late as more evidence has emerged that classic celiac disease with concomitant small intestine destruction and positive intestinal biopsy is not necessarily always present with the disease, especially when digestive complaints are at a minimum. The new paradigm created in this paper embraces, correctly in my estimation, the fact that an intestinal biopsy does not HAVE to be positive for a diagnosis of celiac disease to occur.

Lastly, gluten sensitivity is officially defined as a reaction to gluten that is not a true allergy, nor one that has the autoimmune characteristics of celiac disease, namely tissue destruction of the small intestine. The classic celiac blood tests, tTG and EMA are markers of such destruction, so the authors state that these tests would also be negative in a patient suffering from gluten sensitivity. I concur.

I was also happy to see that the authors mentioned that the blood test that measured anti-gliadin antibodies (AGA) might also found to be positive with the native gluten immune –reaction associated with gluten sensitivity. While they haven’t embraced the AGA test as a conclusive test, they at least mention that it could be a marker. This is a big step in the field that has, up to this point, categorically stated there is absolutely no lab test available to measure gluten sensitivity.

Further, it was mentioned that the symptoms associated with gluten sensitivity could readily overlap those seen with celiac or wheat allergy patients and those symptoms would resolve with a gluten-free diet. The authors correctly point out that many symptoms associated with gluten sensitivity are extraintestinal in nature – meaning that they are found outside the digestive tract.

This should hopefully give support to those many people who are denied testing because they don’t fit the criteria of classic celiac disease due to their absent digestive complaints. Specifically eczema or skin rash, headaches, foggy thinking, fatigue, depression, anemia and bone or joint pain were noted as common symptoms of gluten sensitivity.

The vast increase of gluten-free food and beverages on the market, to the tune of a 28% compound annual growth between 2004 to 2011, with no signs of slowing in 2012, was assumed by the authors to imply that people far beyond those diagnosed with celiac disease were purchasing these products.

I disagree with the following statement: “The rest of the market is filled either by people who undertake the diet as occasional consumers (no medical necessity) or by individuals affected by maladies that have been claimed to be affected by gluten exposure, including autism spectrum disorder, attention deficit hyperactivity disorder, multiple sclerosis and irritable bowel syndrome, but for which there is no evidence of the effectiveness of the diet.”

Why do I disagree? Simply because there is ample research (plus my own clinical experience) that directly opposes it. Here are the facts:

  1. Later in this same report the authors state: “whereas the implementation of a gluten free diet seems to improve the behavior of a subset of children with autism spectrum disorders (ASD)” [Note: The references they use to support this statement are listed below under references 1 and 2 and Dr Fasano and Dr Sapone, authors of this study, are also listed as authors in this supporting literature.]. I’m not sure how both statements can be made in the same article as they seem to obviously negate each other, unless they mean by ‘effectiveness of the diet’ that a gluten free diet needed to impact greater than a subset of the children afflicted with autism – estimated to be about 20%.


In 2010 Dr Fasano was interviewed by the group “Austism Speaks” and they posted that interview on their blog. Regarding a gluten-free diet and autism spectrum disorder (ASD), this is what Dr Fasano had to say:

“Given the fact that ASD is a complex and heterogeneous condition, it is instrumental to stratify children affected by autism to identify subgroups that can benefit of specific therapeutic interventions, like a gluten free diet.  Therefore, it would be highly desirable to develop specific biomarkers to help identify who would benefit the most by implementing specific interventions, including the gluten free diet.  Therefore, the strict avoidance of gluten-containing grains is the best approach to avoid these inflammatory processes that can be responsible of specific clinical outcomes, including ASD, in a subgroup of individuals genetically at risk to react to gluten.”

In October 2011, I personally shared the stage with Dr Fasano in Indianapolis at a gluten intolerance conference for the lay public of that area. In his lecture he stated that while autism and celiac disease concordance (occurring at the same time) is only 2-3%, for those who had celiac disease, 95% were cured of their autism symptoms with a gluten-free diet. Even more importantly, he went on to state that he found that 20% of autistic kids are actually gluten sensitive and have a leaky gut – that was likely the subset to which he was referring above.

I think you’ll agree that there does seem to be some strong evidence that a gluten free diet can be effective in treating children with autism spectrum disorder.

Clinically, I have seen very good success with a gluten-free diet in autistic as well children suffering from ADHD.

2. In BMC Neurology 2011, in an article titled “Prevalence of celiac disease in multiple sclerosis”, the authors stated and I quote: “We have found an increased prevalence of celiac disease in 8 of the 72 multiple sclerosis patients (11.1%) and also in their first-degree relatives (32%). Therefore, increased efforts aimed at the early detection and dietary treatment of celiac disease, among antibody-positive multiple sclerosis patients, are advisable.”   Obviously with an incidence of celiac disease in the general population of 1%, finding it in multiple sclerosis patients at a prevalence of 11% is worth noting. It is well known that gluten affects the nervous system and it is also well documented that autoimmune diseases tend to occur together – celiac and MS are both autoimmune diseases.

    Clnically, I personally have seen improvement in multiple sclerosis in my patients who have undertaken a gluten-free diet.

    3. In the American Journal of Gastroenterology March 2011, a study titled “Gluten causes gastrointestinal symptoms in subjects without celiac disease: a double-blind randomized placebo-controlled trial” was published. Their purpose was to determine if patients with IBS (irritable bowel syndrome), but without confirmed celiac disease, legitimately improved on a gluten-free diet. The individuals in the study were already using a gluten-free diet to control their IBS symptoms, but they did not have celiac disease and the authors wished to confirm if they ‘really’ were better gluten-free when a double-blind placebo study was undertaken.

    [Note: double-blind randomized placebo-controlled studies are considered the ‘gold standard’ when it comes to research. This study met those criteria.]

    Of the 34 patients who completed the study 56% of them carried the genes for celiac disease. This is compatible with other studies showing about 50% of those with gluten sensitivity do carry those genes despite not having the disease. The patients were very compliant. 68% of those being fed gluten (unbeknownst to them since it was a double-blind placebo study) reported that they felt worse. They were found to be significantly worse within 1 week of beginning the gluten-containing diet. Symptoms such as pain, bloating, fatigue and stool consistency all worsened. The control group not receiving gluten did not suffer these symptoms.

    The authors concluded that non-celiac gluten sensitivity may very well be a legitimate condition, although they admitted that they didn’t fully understand the mechanism behind it. [Note: they are not alone and that is why more research needs to be done.]

    In my personal 20+ years of clinical experience, there are few cases of IBS that I and my fellow clinic doctors have treated who were not helped with a gluten-free diet. Typically the elimination of gluten from the diet resolved most if not all symptoms. Therefore, looking at the study above, I think it is safe to say that a gluten-free diet has shown ample effectiveness when it comes to IBS.

    Hopefully I have defended the reason for my disagreements with ample research support. However, those disagreements are not the important take-away.  What I feel is most important and valuable is that this report revealed the following:

    • It fully embraced gluten sensitivity as a legitimate condition
    • It acknowledged the AGA test as a potential marker for gluten sensitivity
    • It stated that gluten sensitivity often accompanies symptoms outside the digestive tract and they range from skin issues, to behavioral, to joint pain and more
    • It points out that an intestinal biopsy does not have to be positive for a diagnosis of celiac disease
    • And lastly, that much more research needs to occur to fully understand the mechanism that underlies gluten sensitivity and appreciate the percentage of the world population affected.

    You can now show this study to your doctor (it is not written for lay people) and this article to your friends. No longer does anyone need to believe that gluten cannot possibly be affecting their health simply because they have negative celiac blood tests or biopsy. With this data you can educate your doctor that gluten sensitivity does not require the devastating digestive symptoms and loss of weight associated with classic celiac disease. Quite the contrary, gluten sensitive patients are frequently without digestive complaints altogether and suffer, rather, from symptoms outside the digestive tract.

    And finally, patients with symptoms from fatigue to schizophrenia, from joint pain to depression, and from seizures to skin problems, can insist on finding out whether their symptoms are caused by an intolerance to gluten. We now know there is a vast array of symptoms and diseases (over 300) associated with gluten intolerance and they are far beyond what many doctors are aware of.

    I hope this was helpful for you. Please share this information with your doctor, your family and friends. It is only through increased awareness that we will begin to diagnose all those patients with celiac disease and gluten sensitivity who remain undiagnosed or misdiagnosed and suffer terrible health consequences as a result.

    I am happy to answer any questions you may have and am delighted to assist you with your health should you require help. Contact me for a free health analysis by calling 408-733-0400.

    To your good health,

    Dr Vikki Petersen, DC, CCN
    Founder of HealthNOW Medical Center
    Co-author of “The Gluten Effect”
    Author of the eBook: “Gluten Intolerance – What you don’t know may be killing you!”



    1. Cascella NG, Kryszak D, Bhatti B, Gregory P, Kelly DL, Mc Evoy JP, Fasano A, Eaton WW: Prevalence of celiac disease and gluten sensitivity in the United States clinical antipsychotic trials of intervention effectiveness study population. Schizophenia Bulletin 2011, 37:94-100.
    2. de Magistris L, Familiari V, Pascotto A, Sapone A, Frolli A, Iardino P, Carteni M, De Rosa M, Francavilla R, Riegler G, Militerni R, Bravaccio C: Alterations of the intestinal barrier in patients with autism spectrum disorders and in their first-degree relatives. Journal of Pediatrics Gastroenterology & Nutrition 2010, 51:418-424
    3. BMC Neurology 2011, 11:31doi:10.1186/1471-2377-11-31
    4. American Journal of Gastroenterology. 2011 Mar;106(3):508-14; quiz 515. Epub 2011 Jan 11.
    5. Anna Sapone, Julio C Bai, Carolina Ciacci, Jernej Dolinsek, Peter HR Green, Marios Hadjivassiliou, Katri Kaukinen, Kamran Rostami, David S Sanders, Michael Schumann, Reiner Ullrich, Danilo Villalta, Umberto Volta, Carlo Catassi, and Alessio Fasano: “Spectrum of gluten-related disorders: consensus on new nomenclature and classification” BioMed Central February 2012.



    How Fast Food Weakens the Immune System

    The immune system of the body is a complex and intricate system designed to defend and repair.  80% of it is located in the gut. This is a significant point to remember.

    When it finds “strange” or “danger” signals present, the immune system reacts. By the same token it also is responsible for repair.  This is why so much damage occurs from drugs that suppress it (immunosuppressive drugs) such as steroids.  With the immune system suppressed, no proper repair occurs, bones weaken, healing is poor and the body is in danger of contracting serious disease.

    Tolerance is the normal response of the immune system to unknown but non-dangerous substances.  Without tolerance we would be allergic to and attacking everything that was new or different in our environment or food.

    Let’s look a little deeper into this: White blood cells are the major cells the body produces to help fight infection. T cells are lymphocytes (or specialized white blood cells) that can attack “bugs” with highly specific mechanisms. They make specific receptors for every possible good and bad guy you encounter. It would be similar to getting fingerprints and a retina scan of an intruder so that you would know very precisely if that intruder tried to enter your home again.

    Innate immunity recognizes what’s foreign and dangerous and can orchestrate a gross level response such as a bleach attack or use of other destructive material. It doesn’t require a previous exposure to the substance to decide whether it’s bad or not.

    Here an analogy would be seeing a strange figure moving in your house and simply throwing acid at it.  It’s not as precise as the fingerprints and retina scan but it gets the job done.

    The first line of defense is our rather crude, innate immunity response. Adaptive immunity is the secondary response and it does require the previous presence of the bad guy (or antigen) to know that an attack is necessary.

    Cells known as dendritic cells are part of the secondary response. They ingest bad guys (called antigens) and present them to white blood cells (lymphocytes) so that they can make the proper substance to destroy them (called antibodies).

    A specific antibody is made to destroy a specific antigen – they are like locks and keys. Dendritic cells decide if the “world” is safe or not and they prime other cells to become activated.

    Dendritic cells respond to an unhealthy diet because they also sample what’s in the gut. Recent research showed that inflammation created after eating typical “fast food” lasted for 3 hours and the response of the body’s immune system to the junk food was similar to what occurred when a pathogenic microbe (such as a bacteria) entered the body. It is considered that chronic overeating and a poor diet could result in permanent increases in pro-inflammatory substances in the body that would in turn create disease such as obesity, heart disease and cancer. We always knew there was a trigger to chronic inflammation, now we know that diet plays a major role.

    Dendritic cells are the supervisors that ensure that lymphocytes don’t attack the body itself but only bad guys. To ensure that happens, the immune system has special cells called T regulatory cells that suppress the body from attacking self and help to retain tolerance. So there is a built-in safety mechanism when all is functioning as designed.

    What if the T regulatory cells are suppressed? You can then develop autoimmune disease because there is nothing stopping the immune system from overreacting. Stress is known to inhibit T regulatory cells while Vitamin D and tai chi optimizes them. Probiotics are anti-inflammatory and they actually help to create more Tregulatory cells, thereby balancing the immune response and preventing inflammation.  Take note: this is a VERY good thing!

    While transient inflammation is normal when the body is battling infections or toxins or repairing from a trauma, chronic inflammation signals a loss of tolerance and is a precursor to many leading causes of death.  Further, localized inflammation can create a systemic inflammatory response. Look at gum disease, a local inflammation that increases one’s risk of heart disease.

    Sometimes when inflammation is occurring in the body NSAID drugs are prescribed.  NSAID stands for non-steroidal anti-inflammatory drugs. This category includes drugs such as aspirin, motrin, ibuprofen, and naproxen. You may find it interesting that while these drugs temporarily reduce inflammation, over time they create a leaky gut, immune system stress, and actually create increased inflammation! They cause the exact problem they’re supposed to be treating. (Such a phenomena is not unusual with drugs – read the fine print of side effects and you’ll find this to be a common issue.)

    It turns out that the immune system doesn’t just react to bacteria, viruses and cancer cells.  A poor diet can cause it to become activated, as does a food sensitivity such as gluten. Unfortunately its responses can be quite dramatic, resulting in damage to the gut lining and thereby creating a leaky gut.  The liability of a leaky gut is the mobilization of toxins from within the gut (endotoxins), now being found in the blood stream. This creates a large stress upon the immune system and chronic inflammation can result.

    Whether the immune system is over-responsive or accurate in how it responds to a threat has much to do with the health and integrity of the small intestine. We know that NSAID drugs, aspirin, steroids, stress and food reactions can create destruction and leakiness.  Similarly we know that excess sugar and unhealthy fast food diminishes the immune system’s healthy response abilities for 3 to 4 hours. On the positive side we know that a diet high in anti-oxidants, Vitamin D, tai chi and probiotics are all extremely positive in strengthening and causing an appropriate response from the immune system.

    If I now commented that food and lifestyle are” information” that you feed your immune system would that make sense? Making poor dietary and lifestyle choices and wondering why the body doesn’t feel good is akin to dropping a hammer on your foot and wondering where the pain is coming from!

    The immune system is smart but it can get overwhelmed and confused with the wrong input and stressors.  It can be normalized, but we must start by assisting it where it lives: the gut!

    Dr Vikki Petersen
    Founder of HealthNOW Medical Center
    Co-author of “The Gluten Effect”

    Published in IAACN INSIGHT.  Volume 12, Number 2

    (Official Publications of the International and American Associations of Clinical Nutritionists)

    Case History: Elliot B.

    •42 year old male
    •Weight: 268 lb.  Height: 5′ 10 ½”
    •BP 140/90

    Main Complaint:

    •IBS – symptoms for 20 years but diagnosed 5 years ago and getting worse.
    •BM: 7 – 8 times/day.  Diarrhea, mostly liquid.
    •1 to 2 x/mo will pass blood with bowel movements if has more movements than usual.
    •Bloating, gas and heartburn.
    •Abdominal pain and gurgling.

    Secondary Complaints:

    •Extremely depressed.
    •Very irritable and anxious.
    •Loud noises bother him; he’s startled easily and easily upset.
    •Severe claustrophobia.  Never had the problem 20 years ago – can’t get into a car w/ others unless he’s driving.
    •Can’t drive anywhere unless he knows exactly where the bathrooms are.
    •Sums up his problem as debilitating.  Had to quit his job and become a consultant so that he could work from home.
    •He can’t do any hobbies or desired activities.
    •When family went on vacation he would stay in his room.
    •Won’t go outside the house much – gets worried about leaving home.

    History / Family History

    •Had gas pains as a child and thinks he’s always been lactose intolerant.
    •Feels good at 200 lb but currently weighs 268lb; recently gained 20 lb.
    •Drug use: abused drugs in 1980s; underwent rehab for cocaine.
    •Sister who is anorexic and also has drug abuse history.

    Current Medical Diagnosis

    2.Obesity (BMI 37)

    Diet Diary

    •Breakfast – fast food
    •Lunch – subway sandwich or tacos – fast food
    •Dinner – fast food or chicken, rice and veggies (at home)
    •Snacks – pretzels, cookies, fruit, crackers
    •Needs coffee to get going in the morning
    •Drinks 3 litres of diet soda/day.


    •Lexapro 10 mg/day.  4 years ago was on Paxil, it stopped working so switched to Lexapro.
    •Lorazapan for anxiety as needed for 5 years.
    •Ativan – as needed


    •Discover the source of the bowel irritation.  Rule out food reactions and infections.
    •After removing any irritants, heal the bowels.
    •Evaluate adrenal function.
    •Educate on healthy diet.

    Lab Tests:

    •Stool analysis
    •Adrenal profile – salivary testing
    •Comprehensive blood analysis – fasting
    •Gluten test – blood and saliva

    Results of laboratory tests:

    •H. pylori, Clostridium Difficile toxin A and moderate Proteus species were identified.
    •Stage II adrenal fatigue with low afternoon cortisol, low DHEA and very high cortisol : DHEA ratio.
    •Cholesterol – 216
    •Direct LDL – 150 (high)
    •Total Fe binding capacity – 401 (high)
    •Cortisol (blood)- 4.85 ( very low)
    •Hemoglobin A1C – 6.10 (high)
    •Gliadin – borderline in saliva, negative in blood


    •Modified Elimination Diet – eliminating the most common food allergies from the diet for 10 days followed by a reintroduction.
    •Lifestyle and dietary management.
    •Antibiotic therapy to treat H. pylori and C. Difficile infections followed by probiotics.
    •Supplements to support adrenal function, enzymes, B12 injections and sublingual B12 on days not receiving injections.

    Current Status:

    Best communicated from a report written by the patient after being on the program for 90 days:

    IBS ruled my life.  I could not go anywhere where I was not absolutely sure that there was a close bathroom.  I tried to take over the counter and prescription diarrhea medicine, but it would only last a few hours.  Because of my symptoms, I was also on depression medication on a daily basis to “help” me deal with the anxiety that was caused by my IBS.  I also suffered from extreme claustrophobia, and could not travel in my car without stopping to go to the bathroom every 20 minutes or so.  I would say on a good day I had 6-7 bowel movements and on a bad day 8-9 – every day.  I have had IBS for the last 20 years, but this bad, only for the last 2-3 years.

    I could not go skiing, running or walking outdoors.  Traveling was a nightmare for me and my family.  I was always stressed about when I would have to next go to the restroom.

    I remember at our first meeting Dr Petersen told me that she could help me, not with arrogance, but with confidence.  She showed me pictures of what my insides probably looked like, but explained it in an easy to understand, matter of fact way.  Dr Petersen told me I would have to give up eating like I was (eating myself to death, or a certain heart attack), but I could do it gradually.

    I was given a diet that included none of the things I had been eating or drinking.  It included giving up caffeine and gluten and sugar and aspartame.  I had come to the clinic willing to try anything and I knew it would be hard but nothing could have prepared me for the withdrawal from caffeine and sugar.  I thought that during the first week I was getting sicker, but I made it through.  No real progress on my IBS, but I felt different.  We went through blood tests and saliva tests and stool samples.  It turned out I had 2 infections in my intestines that were not letting me digest food.  The antibiotics at first made me feel even worse, but I was in this for the long haul.  I knew I was on the right track because soon I started to feel better.  Maybe the IBS was not cured yet, but I had more good days than bad, and I felt better emotionally and physically than I had in a long time.  About one week after I finished the antibiotics, I began to lead a normal life.  I was only going to the bathroom 3-4 times a day, and the experience was much better.  Two weeks later, I had a few days in a row with only 2-3 bowel movements per day.  In three days, I had what would have been one of my bad days, but with no anxiety or discomfort.

    The side benefit of my gluten free diet is that I am off of my “maintenance anxiety drug”.  This did not happen because my new doctors told me not to take it, I just forgot to about two weeks ago, and have not had the need for it.  Today I got in a car w/ 4 other men and I wasn’t doing the driving.  It suddenly dawned on me that I would never have done that before.  The anxiety would have prevented me.

    I have also lost 18 pounds, which was not why I came here, but is a definite benefit.

    It is very difficult to explain the pain and suffering that I went through and that I put my family through with my panic attacks and IBS.  I am lucky that they supported me and did not leave me.  I feel that I can start to be the person that I am meant to be.  My life gets better every day.  Maybe everyone is not as sensitive to gluten as I am, but for me it is poison.  It is easy to pass up gluten with the great results I am seeing.  I asked Dr Petersen if it was just the caffeine that made me so irritable.  The doctor explained that for some people gluten is neurotoxic.  This was definitely the case for me and understanding that makes it easy to stay on a gluten free diet.  I also realized that all of the food that made me sick has gluten in it….bagels, bread, pizza, pasta, sandwiches……I was killing myself while trying to eat healthy.  When I had a salad with bread and croutons, it defeated the purpose.

    Anyway…that is my story so far.  I feel better everyday.  I can not thank the Drs Petersen enough for helping me change my life.


    Elliot B.

    Case study submitted by: Drs Vikki and Rick Petersen, DC, CCN.
    HealthNOW Medical Center
    1309 S. Mary Ave., Suite 100
    Sunnyvale, CA 94087

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