This morning, I had a conversation with Dr. Randy Tobler on his radio show "Vital Signs", on 97.1 FM News Talk in St Louis. Dr. Tobler is an obstetrician-gynecologist with an interest in nutrition, fitness and reproductive endocrinology from a holistic perspective. He asked me to appear on his show after he discovered my blog and found that we have some things in common, including an interest in evolutionary/ancestral health. We talked about the history of the American diet, the health of non-industrial cultures, what fats are healthiest, and the difference between pastured and conventional meat/dairy-- we took a few questions from listeners-- it was fun.
The show is available as a podcast here (3/26 show), although as far as I can tell, you need iTunes to listen to it. My section of the show starts around 8:20.
To everyone who arrived here after hearing me on the air this morning: welcome! Here are a few posts to give you a feel for what I do here at Whole Health Source:
The Coronary Heart Disease Epidemic
US Weight, Lifestyle and Diet Trends, 1970-2007
Butter vs. Margarine Showdown
Preventing and Reversing Tooth Decay
The Kitavans: Wisdom from the Pacific Islands
Potatoes and Human Health, Part I, Part II and Part III
Traditional Preparation Methods Improve Grains' Nutritional Value
Real Food XI: Sourdough Buckwheat Crepes
Glucose Tolerance in Non-industrial Cultures
Tropical Plant Fats: Palm Oil
It's Time to Let Go of the Glycemic Index
Sabtu, 26 Maret 2011
Rabu, 23 Maret 2011
Safflower Oil Study
A few people have sent me a new study claiming to demonstrate that half a tablespoon of safflower oil a day improves insulin sensitivity, increases HDL and decreases inflammation in diabetics (1). Let me explain why this study does not show what it claims.
It all comes down to a little thing called a control group, which is the basis for comparison that you use to determine if your intervention had an effect. This study didn't have one for the safflower group. What it had was two intervention groups, one given 6.4g conjugated linoleic acid (CLA; 50% c9t11 and 50% t10c12-CLA) per day, and one given 8g safflower oil. I have to guess that this study was originally designed to test the effects of the CLA, with the safflower oil group as the control group, and that the interpretation of the data changed after the results came in. Otherwise, I don't understand why they would conduct a study like this without a control group.
Anyway, they found that the safflower oil group did better than the CLA group over 16 weeks, showing a higher insulin sensitivity, higher HDL, lower HbA1c (a marker of average blood glucose levels) and lower CRP (a marker of inflammation). But they also found that the safflower group improved slightly compared to baseline, therefore they decided to attribute the difference to a beneficial effect of safflower oil. The problem is that without a control (placebo) group for comparison, there's no way to know if the improvement would have occurred regardless of treatment, due to the season changing, more regular check-ups at the doctor's office due to participating in a study, or countless other unforeseen factors. A control group is essential for the accurate interpretation of results, which is why drug studies always have placebo groups.
What we can say is that the safflower oil group fared better than the CLA group, because there was a difference between the two. However, what I think really happened is that the CLA supplement was harmful and the small dose of safflower oil had no effect. Why? Because the t10c12 isomer of CLA, which was half their pill, has already been shown by previous well-controlled studies to reduce insulin sensitivity, decrease HDL and increase inflammatory markers at a similar dose and for a similar duration (2, 3). The safflower oil group only looked good by comparison. We can add this study to the "research bloopers" file.
It's worth noting that naturally occurring CLA mixtures, similar to those found in pastured dairy and ruminant fat, have not been shown to cause metabolic problems such as those caused by isolated t10c12 CLA.
It all comes down to a little thing called a control group, which is the basis for comparison that you use to determine if your intervention had an effect. This study didn't have one for the safflower group. What it had was two intervention groups, one given 6.4g conjugated linoleic acid (CLA; 50% c9t11 and 50% t10c12-CLA) per day, and one given 8g safflower oil. I have to guess that this study was originally designed to test the effects of the CLA, with the safflower oil group as the control group, and that the interpretation of the data changed after the results came in. Otherwise, I don't understand why they would conduct a study like this without a control group.
Anyway, they found that the safflower oil group did better than the CLA group over 16 weeks, showing a higher insulin sensitivity, higher HDL, lower HbA1c (a marker of average blood glucose levels) and lower CRP (a marker of inflammation). But they also found that the safflower group improved slightly compared to baseline, therefore they decided to attribute the difference to a beneficial effect of safflower oil. The problem is that without a control (placebo) group for comparison, there's no way to know if the improvement would have occurred regardless of treatment, due to the season changing, more regular check-ups at the doctor's office due to participating in a study, or countless other unforeseen factors. A control group is essential for the accurate interpretation of results, which is why drug studies always have placebo groups.
What we can say is that the safflower oil group fared better than the CLA group, because there was a difference between the two. However, what I think really happened is that the CLA supplement was harmful and the small dose of safflower oil had no effect. Why? Because the t10c12 isomer of CLA, which was half their pill, has already been shown by previous well-controlled studies to reduce insulin sensitivity, decrease HDL and increase inflammatory markers at a similar dose and for a similar duration (2, 3). The safflower oil group only looked good by comparison. We can add this study to the "research bloopers" file.
It's worth noting that naturally occurring CLA mixtures, similar to those found in pastured dairy and ruminant fat, have not been shown to cause metabolic problems such as those caused by isolated t10c12 CLA.
Sabtu, 19 Maret 2011
BELIMUMAB: A NEW DRUG FOR LUPUS
The US Food and Drug Administration (FDA) has approved the use of belimumab (Benlysta, Human Genome Sciences and GlaxoSmithKline) in combination with standard therapies to treat active autoantibody-positive systematic lupus erythematosus.
This is the first lupus drug to be approved since 1955, when the FDA approved hydroxychloroquine (Plaquenil) and corticosteroids. In 1948, aspirin was approved to treat lupus.
Belimumab is a B-lymphocyte stimulator protein inhibitor that is thought to decrease the amount of abnormal B cells, which is hypothesized to be a mechanism of action in lupus.
The safety and effectiveness of belimumab was demonstrated in 2 clinical trials that randomized a total of 1684 patients to receive either belimumab or placebo in combination with standard therapy. Treatment with belimumab plus standard therapy reduced disease activity and possibly decreased the number of severe flares and steroid use.
Patients with active lupus that involved the kidneys or central nervous system and those who were previously treated with a B-cell-targeted therapy or intravenous cyclophosphamide were excluded from participating in the trials.
Study participants of African American or African descent did not significantly respond to belimumab. Additional studies will be conducted to definitively determine the safety and efficacy of belimumab in this population.
Common adverse effects reported with belimumab include nausea, diarrhea, fever, and infusion-site reactions. It is suggested that patients be treated with an antihistamine prior to a belimumab infusion.
A greater number of deaths and serious infections were reported in patients treated with belimumab than in those treated with placebo. Live vaccines should not be administered during treatment with belimumab.
It is estimated that lupus afflicts up to 1.5 million Americans, and it disproportionately affects black women.
This is the first lupus drug to be approved since 1955, when the FDA approved hydroxychloroquine (Plaquenil) and corticosteroids. In 1948, aspirin was approved to treat lupus.
Belimumab is a B-lymphocyte stimulator protein inhibitor that is thought to decrease the amount of abnormal B cells, which is hypothesized to be a mechanism of action in lupus.
The safety and effectiveness of belimumab was demonstrated in 2 clinical trials that randomized a total of 1684 patients to receive either belimumab or placebo in combination with standard therapy. Treatment with belimumab plus standard therapy reduced disease activity and possibly decreased the number of severe flares and steroid use.
Patients with active lupus that involved the kidneys or central nervous system and those who were previously treated with a B-cell-targeted therapy or intravenous cyclophosphamide were excluded from participating in the trials.
Study participants of African American or African descent did not significantly respond to belimumab. Additional studies will be conducted to definitively determine the safety and efficacy of belimumab in this population.
Common adverse effects reported with belimumab include nausea, diarrhea, fever, and infusion-site reactions. It is suggested that patients be treated with an antihistamine prior to a belimumab infusion.
A greater number of deaths and serious infections were reported in patients treated with belimumab than in those treated with placebo. Live vaccines should not be administered during treatment with belimumab.
It is estimated that lupus afflicts up to 1.5 million Americans, and it disproportionately affects black women.
Jumat, 18 Maret 2011
New Ancestral Diet Review Paper
Pedro Carrera-Bastos and his colleagues Maelan Fontes-Villalba, James H. O'Keefe, Staffan Lindeberg and Loren Cordain have published an excellent new review article titled "The Western Diet and Lifestyle and Diseases of Civilization" (1). The paper reviews the health consequences of transitioning from a traditional to a modern Western diet and lifestyle. Pedro is a knowledgeable and tireless advocate of ancestral, primarily paleolithic-style nutrition, and it has been my privilege to correspond with him regularly. His new paper is the best review of the underlying causes of the "diseases of civilization" that I've encountered. Here's the abstract:
I gave Pedro my comments on the manuscript as he was editing it, and he was kind enough to include me in the acknowledgments.
It is increasingly recognized that certain fundamental changes in diet and lifestyle that occurred after the Neolithic Revolution, and especially after the Industrial Revolution and the Modern Age, are too recent, on an evolutionary time scale, for the human genome to have completely adapted. This mismatch between our ancient physiology and the western diet and lifestyle underlies many so-called diseases of civilization, including coronary heart disease, obesity, hypertension, type 2 diabetes, epithelial cell cancers, autoimmune disease, and osteoporosis, which are rare or virtually absent in hunter–gatherers and other non-westernized populations. It is therefore proposed that the adoption of diet and lifestyle that mimic the beneficial characteristics of the preagricultural environment is an effective strategy to reduce the risk of chronic degenerative diseases.At 343 references, the paper is an excellent resource for anyone with an academic interest in ancestral health, and in that sense it reminds me of Staffan Lindeberg's book Food and Western Disease. One of the things I like most about the paper is that it acknowledges the significant genetic adaptation to agriculture and pastoralism that has occurred in populations that have been practicing it for thousands of years. It hypothesizes that the main detrimental change was not the adoption of agriculture, but the more recent industrialization of the food system. I agree.
I gave Pedro my comments on the manuscript as he was editing it, and he was kind enough to include me in the acknowledgments.
Kamis, 17 Maret 2011
REDUCING CHEMORADIOTHERAPY SAFE FOR SOMERABDOMYOSARCOMAS
NEW YORK (Reuters Health) Mar 03 - Reducing the use of radiotherapy and eliminating cyclophosphamide has been found safe and effective in some patients with newly diagnosed, low-risk embryonal rhabdomyosarcoma (ERMS).
The findings are the latest from The Intergroup Rhabdomyosarcoma Study Group (IRSG), and were published online February 28th in the Journal of Clinical Oncology.
In previous studies the same researchers who conducted this study found that patients with localized, grossly resected, or gross residual (orbital only) ERMS had 5-year failure-free survival rates of 83% and overall survival rates of 95%. That was using specially designed protocols for low-risk patients established by the IRSG. Those regimens included vincristine and dactinomycin with or without cyclophosphamide and radiation therapy.
The aim of the present study was to see if it was feasible, in a similar cohort of patients, to decrease toxicity by reducing radiotherapy doses and eliminating cyclophosphamide in patients at lowest risk.
The researchers stratified 342 patients by risk. The lower risk group (n=264) included embryonal ectomesenchymoma or ERMS patients categorized as stage 1 group I/IIA, stage 1 group III orbit, or stage 2 group I.
The higher risk group (n=78) included patients with stage 1 group IIB/C, stage I group III nonorbit, stage 2 group II, or stage 3 group I/II ERMS.
The researchers' specific objectives were three-fold:
1. To estimate failure-free survival rates of patients in subgroup A after vincristine and dactinomycin chemotherapy for 45 weeks, plus radiation therapy for patients with residual tumor;
2. To estimate failure-free survival rates of patients in subgroup B after vincristine and dactinomycin plus cyclophosphamide for 45 weeks, plus radiation therapy for patients with residual tumors;
3. And to ascertain local control and failure-free survival rates in three selected groups of patients given radiation therapy doses 5-10 Gy lower than in previous studies: 36 Gy for stage 1 group IIA, 45 Gy for stage 1 group III N0 orbit, and 36 Gy for stages 2/3 group IIA patients.
Estimated 5-year failure-free survival rates were 89% for patients in the lower risk group, and 85% for the higher risk group, after median follow-up of 5.1 years.
For patients with stage 1 group IIA tumors (n=62), estimated 5-year failure-free survival rates were 81%. For patients with group III orbit tumors (n=77), estimated 5-year failure-free survival was 86%.
The study group says 5-year failure-free survival and overall survival were similar to that observed in IRS-III patients, including those that were treated with reduced doses of radiation. Failure-free survival and overall survival were lower, however, than comparable IRS-IV patients that received vincristine and dactinomycin plus cyclophosphamide. Five-year failure-free survival rates were similar among the lower risk and higher risk patients.
Rhabdomyosarcoma is the most common type of soft-tissue sarcoma in children. The annual incidence of the disease in the U.S. is 4.5 cases per 1 million children younger than 14 years. About 250 new cases are diagnosed each year, nearly two thirds being embryonal rhabdomyosarcomas.
The findings are the latest from The Intergroup Rhabdomyosarcoma Study Group (IRSG), and were published online February 28th in the Journal of Clinical Oncology.
In previous studies the same researchers who conducted this study found that patients with localized, grossly resected, or gross residual (orbital only) ERMS had 5-year failure-free survival rates of 83% and overall survival rates of 95%. That was using specially designed protocols for low-risk patients established by the IRSG. Those regimens included vincristine and dactinomycin with or without cyclophosphamide and radiation therapy.
The aim of the present study was to see if it was feasible, in a similar cohort of patients, to decrease toxicity by reducing radiotherapy doses and eliminating cyclophosphamide in patients at lowest risk.
The researchers stratified 342 patients by risk. The lower risk group (n=264) included embryonal ectomesenchymoma or ERMS patients categorized as stage 1 group I/IIA, stage 1 group III orbit, or stage 2 group I.
The higher risk group (n=78) included patients with stage 1 group IIB/C, stage I group III nonorbit, stage 2 group II, or stage 3 group I/II ERMS.
The researchers' specific objectives were three-fold:
1. To estimate failure-free survival rates of patients in subgroup A after vincristine and dactinomycin chemotherapy for 45 weeks, plus radiation therapy for patients with residual tumor;
2. To estimate failure-free survival rates of patients in subgroup B after vincristine and dactinomycin plus cyclophosphamide for 45 weeks, plus radiation therapy for patients with residual tumors;
3. And to ascertain local control and failure-free survival rates in three selected groups of patients given radiation therapy doses 5-10 Gy lower than in previous studies: 36 Gy for stage 1 group IIA, 45 Gy for stage 1 group III N0 orbit, and 36 Gy for stages 2/3 group IIA patients.
Estimated 5-year failure-free survival rates were 89% for patients in the lower risk group, and 85% for the higher risk group, after median follow-up of 5.1 years.
For patients with stage 1 group IIA tumors (n=62), estimated 5-year failure-free survival rates were 81%. For patients with group III orbit tumors (n=77), estimated 5-year failure-free survival was 86%.
The study group says 5-year failure-free survival and overall survival were similar to that observed in IRS-III patients, including those that were treated with reduced doses of radiation. Failure-free survival and overall survival were lower, however, than comparable IRS-IV patients that received vincristine and dactinomycin plus cyclophosphamide. Five-year failure-free survival rates were similar among the lower risk and higher risk patients.
Rhabdomyosarcoma is the most common type of soft-tissue sarcoma in children. The annual incidence of the disease in the U.S. is 4.5 cases per 1 million children younger than 14 years. About 250 new cases are diagnosed each year, nearly two thirds being embryonal rhabdomyosarcomas.
Senin, 14 Maret 2011
Gluten-Free January Survey Data, Part II: Health Effects of a Gluten-Free Diet
GFJ participants chose between three diet styles: a simple gluten-free diet; a "paleo light" diet diet that eliminated sugar and industrial seed (vegetable) oils in addition to gluten; and a "paleo full monty" diet that only included categories of food that would have been available to our pre-agricultural ancestors. The data in this post represent the simple gluten-free diet group, and do not represent the other two, which I'll analyze separately.
To get the data I'll be presenting below, first I excluded participants who stated on the survey that they did not adhere to the diet. Next, I excluded participants who were gluten-free before January, because they would presumably not have experienced a change from continuing to avoid gluten. That left us with 53 participants.
For each of these graphs, the vertical axis represents the number of participants in each category. They won't necessarily add up to 53, for several reasons. The most common reason is that for the questions asking about changes in health conditions, I didn't include responses from people who didn't have the condition in question at baseline because there was nothing to change.
Question #1: What is your overall opinion of the effect of gluten free January on you?
Participants had a very positive experience with the gluten-free diet. Not one person reported a negative overall experience.
Question #2: Did you note a weight change at the end of gluten free January?
And here are the data for people who described themselves as overweight at baseline:
Two-thirds of people who were overweight at baseline lost weight, and only one person out of 37 gained weight. That is striking. A number of people didn't weigh themselves, which is why the numbers only add up to 37.
Question #3: Before January 2011, did you have a problem with intestinal transit (frequent constipation or diarrhea)? If so, did your symptoms change during the month of January?
Responses are heavily weighted toward improvement, although there were a few instances where transit worsened. Transit problems are one of the most common manifestations of gluten sensitivity.
Question #4: Before January 2011, did you have frequent digestive discomfort (pain, bloating, etc.)? If so, did your symptoms change during the month of January?
Digestive discomfort was common, and the gluten-free diet improved it in nearly everyone who had it at baseline. I find this really impressive.
Question #5: Before January 2011, did you have acid reflux? If so, did your symptoms change during the month of January?
Acid reflux responded well to a gluten-free diet.
Question #6: Before January 2011, did you have a problem with tiredness/lethargy? If so, did your symptoms change during the month of January?
Lethargy was common and generally improved in people who avoided gluten. This doesn't surprise me at all. The recent controlled gluten study in irritable bowel syndrome patients found that lethargy was the most reliable consequence of eating gluten that they measured (1, 2). That has also been my personal experience.
Question #7: Before January 2011, did you have a problem with anxiety? If so, did your symptoms change during the month of January?
Anxiety tended to improve in most participants who started with it.
Question #8: Before January 2011, did you have a problem with an autoimmune or inflammatory condition? If so, did your symptoms change during the month of January?
Autoimmune and inflammatory conditions tended to improve in the gluten-free group, although one person experienced a worsening of symptoms.
Question #9: If you ate gluten again or did a gluten challenge after gluten free January, what was the effect?
Just under half of participants experienced moderate or significant negative symptoms when they re-introduced gluten at the end of the month. Two people felt better after re-introducing gluten.
Conclusion
I find these results striking. Participants overwhelmingly improved in every health category we measured. Although the data may have been somewhat biased due to the 53% response rate, it's indisputable that a large number of participants, probably the majority, benefited from avoiding gluten for a month. At some point, we're going to compile some of the comments people left in the survey, which were overwhelmingly positive. Here's a typical comment in response to the question " In your own words, how would you describe your January 2011 experience" (used with permission):
To get the data I'll be presenting below, first I excluded participants who stated on the survey that they did not adhere to the diet. Next, I excluded participants who were gluten-free before January, because they would presumably not have experienced a change from continuing to avoid gluten. That left us with 53 participants.
For each of these graphs, the vertical axis represents the number of participants in each category. They won't necessarily add up to 53, for several reasons. The most common reason is that for the questions asking about changes in health conditions, I didn't include responses from people who didn't have the condition in question at baseline because there was nothing to change.
Question #1: What is your overall opinion of the effect of gluten free January on you?
Participants had a very positive experience with the gluten-free diet. Not one person reported a negative overall experience.Question #2: Did you note a weight change at the end of gluten free January?
And here are the data for people who described themselves as overweight at baseline:
Two-thirds of people who were overweight at baseline lost weight, and only one person out of 37 gained weight. That is striking. A number of people didn't weigh themselves, which is why the numbers only add up to 37.Question #3: Before January 2011, did you have a problem with intestinal transit (frequent constipation or diarrhea)? If so, did your symptoms change during the month of January?
Responses are heavily weighted toward improvement, although there were a few instances where transit worsened. Transit problems are one of the most common manifestations of gluten sensitivity.
Question #4: Before January 2011, did you have frequent digestive discomfort (pain, bloating, etc.)? If so, did your symptoms change during the month of January?
Digestive discomfort was common, and the gluten-free diet improved it in nearly everyone who had it at baseline. I find this really impressive.
Question #5: Before January 2011, did you have acid reflux? If so, did your symptoms change during the month of January?
Acid reflux responded well to a gluten-free diet.Question #6: Before January 2011, did you have a problem with tiredness/lethargy? If so, did your symptoms change during the month of January?
Lethargy was common and generally improved in people who avoided gluten. This doesn't surprise me at all. The recent controlled gluten study in irritable bowel syndrome patients found that lethargy was the most reliable consequence of eating gluten that they measured (1, 2). That has also been my personal experience.Question #7: Before January 2011, did you have a problem with anxiety? If so, did your symptoms change during the month of January?
Anxiety tended to improve in most participants who started with it.Question #8: Before January 2011, did you have a problem with an autoimmune or inflammatory condition? If so, did your symptoms change during the month of January?
Autoimmune and inflammatory conditions tended to improve in the gluten-free group, although one person experienced a worsening of symptoms. Question #9: If you ate gluten again or did a gluten challenge after gluten free January, what was the effect?
Just under half of participants experienced moderate or significant negative symptoms when they re-introduced gluten at the end of the month. Two people felt better after re-introducing gluten.Conclusion
I find these results striking. Participants overwhelmingly improved in every health category we measured. Although the data may have been somewhat biased due to the 53% response rate, it's indisputable that a large number of participants, probably the majority, benefited from avoiding gluten for a month. At some point, we're going to compile some of the comments people left in the survey, which were overwhelmingly positive. Here's a typical comment in response to the question " In your own words, how would you describe your January 2011 experience" (used with permission):
Amazing! I would recommend the experiment to anyone. I felt completely more alert, and less bloated. When I ate some gluten at the close of the experiment, I felt gross, bloated, and lethargic.I think it's worth mentioning that some participants also eliminated other starches, particularly refined starches. Judging by the comments, the diet was probably lower in carbohydrate for a number of participants. We may try to assess that next year.
Kamis, 10 Maret 2011
Gluten-Free January Survey Data, Part I: Demographics and Limitations
Thanks to Matt Lentzner for organizing Gluten-Free January, and everyone who participated and completed the survey, we have a nice data set illustrating what happens when a group of people stop eating gluten for a month. Janine Jagger, Matt and I have been busy analyzing the data, and I'm ready to begin sharing our findings.
GFJ had over 500 participants, 527 of which received the survey and 279 of which completed the survey at the end of the month. Of those who received the survey, 53 percent completed it. I think these are respectable numbers for a survey of this nature, and it reflects the conscientious nature of the people who participated in GFJ.
Demographics
Although respondents were primarily from the United States, I'm happy to say that the data represent 18 different nationalities:
Respondents represented a diversity of ages, the largest group being 30-39 years old, with similar numbers in the 20-29 and 40-49 year groups.
Respondents were just under 2/3 women.
Respondents represented a variety of weights, but the sample was biased toward lean people, in comparison with the general population. There were not many obese participants.
Overall, I was pleased to see that the demographics were quite diverse, particularly in the age and gender categories.
Limitations
There are a few caveats to keep in mind when interpreting the survey results:
GFJ had over 500 participants, 527 of which received the survey and 279 of which completed the survey at the end of the month. Of those who received the survey, 53 percent completed it. I think these are respectable numbers for a survey of this nature, and it reflects the conscientious nature of the people who participated in GFJ.
Demographics
Although respondents were primarily from the United States, I'm happy to say that the data represent 18 different nationalities:
Respondents represented a diversity of ages, the largest group being 30-39 years old, with similar numbers in the 20-29 and 40-49 year groups.
Respondents were just under 2/3 women.
Respondents represented a variety of weights, but the sample was biased toward lean people, in comparison with the general population. There were not many obese participants.
Overall, I was pleased to see that the demographics were quite diverse, particularly in the age and gender categories.Limitations
There are a few caveats to keep in mind when interpreting the survey results:
- GFJ participants do not represent a random cross-section of the population at large. They represent primarily health-conscious individuals who were motivated enough to make a substantial dietary change. In addition, many of the people who participated probably did so because they already suspected they had a problem with gluten.
- The survey response rate was 53%. Although I think that's a reasonable number considering the circumstances, it leaves open the possibility that survey responders differ from non-responders. It's conceivable that participants with better adherence and better outcomes were more likely to complete the survey than those who did not adhere to the diet or had neutral or unfavorable outcomes, despite our efforts to encourage everyone to complete the survey regardless of adherence or outcome. So the results could be biased toward positive outcomes, meaning that we will need to see a strong effect for it to be believable.
- This was a non-blinded diet trial without a control group. There's no way to know how much of the effect was due to avoiding gluten per se, how much was due to overall changes in diet patterns, and how much was a placebo effect.
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