Again, not wanting to jump the gun, in 2015 before I made “official” recommendations, I decided to conduct a survey of Hashimoto’s patients. I wanted to know how many people felt better with which dietary protocol, how many people felt worse, and how many people were able to reduce their thyroid antibodies with a dietary protocol. Although I am a big believer in the patient experience and I always recommend trusting your own body as a guide as to what is working best for you, I decided to include a reduction in antibodies as an objective measure.
Objective measures, such as a reduction in thyroid antibodies, are the types of evidence scientists and doctors prefer to track to determine the severity of a condition and whether the improvements seen by patients are measurable and “real.” Generally speaking, the higher the number of thyroid antibodies, the more aggressive the attack on the thyroid gland, so seeing a reduction in thyroid antibodies is a potential indication that the condition is becoming less aggressive.
Over two thousand people answered the survey, and the results were astounding: over 70 percent of respondents reported improvements based on six nutritional modifications. (You can see more on the specific results in the accompanying table.) The big diet winner for most people with Hashimoto’s was the gluten-free diet! Eighty-eight percent of people felt better gluten free, and up to 33 percent saw a reduction in thyroid antibodies with the removal of gluten.
Furthermore, 81 percent of people reported feeling better following a grain-free and Paleo diet. Additionally, 79 percent of people felt better off dairy, and another 63 percent felt better off soy. Eating a diet that was blood-sugar balanced helped 76 percent of people feel better. Less than 5 percent of people reported feeling worse with these types of dietary regimens. Furthermore, more than 25 percent of people reported reducing their thyroid antibodies with a diet based on food-sensitivity tests, the autoimmune Paleo diet, and the soy-free, gluten-free, grain-free, Paleo, and Low FODMAP (fermentable oligo-, di-, and monosaccharides and polyols) approaches.
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2015 SURVEY OF 2,232 PEOPLE WITH HASHIMOTO’S
DIET TYPE
FELT BETTER
FELT WORSE
REDUCED THYROID ANTIBODIES
Based on food-sensitivity test results
62%
4.2%
43%
Autoimmune Paleo Diet
75%
4%
38%
Soy free
63%
1.2%
34%
Gluten free
88%
0.73%
33%
Grain free
81%
0.74%
28%
Paleo
81%
3.2%
27%
Low FODMAP
39%
0%
27%
Vegan
30%
28%
23%
Low Glycemic Index
76%
2.3%
22%
Dairy free
79%
1.5%
20%
Egg free
47%
3%
19%
Nightshade free
48%
2%
14%
Red meat avoidance
40%
14%
8%
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Although I conducted this survey with a likely biased group (most survey takers were my educated readers), I was pleased that a new research study came out in 2016 that echoed very similar results—and the results were seen in as little as three weeks!
GROWING SCIENTIFIC SUPPORT
In the 2016 study, 180 people with Hashimoto’s were randomized to receive either the study diet or a standard low-calorie diet. Ultimately 108 patients followed the study diet, and 72 patients served as the control group. Those in the control group ate a low-calorie diet without any food restrictions or guidelines. Thyroid antibodies (TPO antibodies, TG antibodies, and antimicrosomal antibodies), TSH, free T3, and free T4 as well as body weight, mass, and composition were measured before the start of the study and after the study ended three weeks later in both the study group and the control group.
After just twenty-one days, all the patients in the study group showed a significant decrease in the levels of thyroid antibodies, which are known to indicate how aggressive the attack is on the thyroid gland. This means that their condition was getting better! The antibodies decreased as follows:
TG antibodies dropped by 40 percent (−40 percent, P<−0.013).
TPO antibodies dropped by 44 percent (−44 percent, P< 0.029).
Antimicrosomal antibodies dropped by 57 percent (−57 percent, P< 0.000).
I consider a drop of 10 percent or more in antibodies an improvement, and you can see the numbers above show decreases of 40, 44, and 57 percent—these were amazing results to see!
In contrast, the people following the “normal diet” saw an increase in thyroid antibody markers. This means that their condition was worsening:
TG antibodies increased by 9 percent (+9 percent, P<0.017).
TPO antibodies increased by 16 percent (+16 percent, P<0.004).
Antimicrosomal antibodies increased by 30 percent (+30 percent, P<0.028).
After twenty-one days, those following the study diet also showed a slight decrease in body weight, body mass index, and lost fat mass: “With regard to the body parameters measured in patients who followed this diet, reduction in body weight (−5 percent, P<0.000) and body mass index (−4 percent, P<0.000) were observed.”
I’m guessing you probably want to know about the diet, right?! It consisted of 12 to 15 percent carbohydrates, 50 to 60 percent protein, and 25 to 30 percent fat (compare this to the standard Western diet, which contains 50 percent carbohydrates, 15 percent protein, and 35 percent fat). Additional specifics:
Veggie rich: Patients were told to eat vegetables, including large leafy greens (but to exclude goitrogens, foods that can interfere with thyroid function).
Included meats: Patients were told to eat only lean parts of red and white meat and were also allowed to eat fish.
Excluded goitrogens: The goitrogens that patients were told to eliminate were “cruciferous [vegetables] of the (Brassicaceae) family (rapeseed or canola, cabbage, turnip, watercress, arugula, radish, horseradish), milk, soy, spinach, millet, tapioca, and lettuce, including certain food additives (e.g., nitrates used for fish and meat preservation).”
Additional exclusions: Other items excluded were eggs, legumes, dairy products, bread, pasta, fruit, and rice.
I was really excited to see that a diet very similar to what I’ve been recommending since 2012 now had research to back it up! There were a couple notable differences between this diet and my Root Cause Dietary Approach to Hashimoto’s.
In the Root Cause Approach, not all goitrogens are created equal. A goitrogen is a name for any substance that has the potential to interfere with thyroid function. The tricky part is that not all of them work in the same way. I like to look at research studies and clinical outcomes before I determine if a food is on the “No” list for Hashimoto’s. There are certain goitrogenic mechanisms that make me cautious right off the bat, such as the inhibition of either the thyroid peroxidase enzyme or the thyroid hormone release. I do recommend avoiding certain goitrogens that do this, including milk, soy, and iodine excess.
I also look at the scientific and clinical evidence showing that a substance may be harmful to the thyroid. Research studies have documented that canola (made from rapeseed) and nitrates found in processed foods have direct toxic effects on the thyroid gland. However, the evidence of harm from other goitrogens such as cruciferous vegetables (broccoli, cabbage, turnips, and the like) is lacking.
The goitrogen categorization of crucifers is due to the fact that they contain substances known as glucosinolates. Glucosinolates, when consumed in large quantities, can
prevent the absorption of iodine into the thyroid gland. This could be a major issue in someone who has iodine deficiency–induced hypothyroidism (iodine deficiency used to be a top cause of hypothyroidism in the 1950s). However, most people with Hashimoto’s today do not have an iodine deficiency, and most cruciferous vegetables do not have enough glucosinolates to induce iodine deficiency.
In my experience, most cruciferous vegetables are well tolerated and offer health benefits for most people with Hashimoto’s. They help the body detoxify, especially when cooked, fermented, or lightly steamed. Even in their raw state, I have not seen issues with cruciferous vegetables in most clients, with the exception of those with small intestinal bacterial overgrowth (SIBO) (because crucifers are high in FODMAPs, which aggravate SIBO) and in those with CBS genetic mutation (due to the high sulfur content of crucifers). If I have a client with concerns about iodine deficiency and crucifers, I recommend steaming, cooking, or fermenting the vegetables. This alone will be enough to break down the small amount of glucosinolates contained in them.
In the Root Cause Approach, there’s no set carb/protein/fat ratio. I don’t recommend a set of macronutrient percentages for everyone. Instead, I often have people play around with their ratios of carbs to protein to fat to find what fits them best. Some people (especially if they’re more active) benefit from more protein. Others benefit from more fat, such as those with brain fog, pain, and depression. Some may even benefit from ketosis (the use of fat instead of carbs as fuel). The bottom line is that you have to adjust the diet to your needs, and your needs may change!
There were some limitations to the 2016 research study. Based on the way it was conducted, it’s difficult to tell whether the carb restriction, goitrogen restriction, avoiding highly reactive foods (gluten, dairy, soy, eggs), or all of the above played a role in improving patient outcomes.
I also wish that the control group was an actual control group (the control group should have kept eating their “normal” diet) and that “low-calorie” was defined. How low are we talking? Some low-calorie diets specify a total of 800 calories, some 1,500. Obviously, there’s a big difference between the two!
Last, I would love to see a study that isolated a low-carb diet versus allergen avoidance and goitrogens. This would offer even greater clarity on what specific modifications were most successful. I would especially like the myth of goitrogen avoidance put to bed, because it’s a common misconception in Hashimoto’s circles that these are all bad, all the time, and this is simply not true.
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TOO MUCH IODINE?
Scientists have long known that iodine is a crucial nutrient for thyroid health. In fact, iodine deficiency is the primary reason for hypothyroidism worldwide. In an effort to reduce the incidence of hypothyroidism, public-health officials began adding iodine to the salt supplies in many industrialized countries. However, this effort backfired, as iodine turned out to be a narrow therapeutic index nutrient, or a “Goldilocks nutrient.” A deficiency of iodine created hypothyroidism due to a lack of building materials for thyroid hormone, but an excess of it also created hypothyroidism, but through a different mechanism. Today, iodine excess is recognized as a risk factor for developing Hashimoto’s!
This has to do with the way that iodine is processed in the body. Iodine from foods and supplements is processed by the thyroid gland so that the body can properly use it. During this process, hydrogen peroxide, a free radical, is released. In cases when the body has adequate levels of selenium and it is used properly, the selenium neutralizes the hydrogen peroxide. However, in cases of iodine excess, excess hydrogen peroxide can cause oxidative damage to the thyroid gland.
The use of iodine supplementation in autoimmune thyroid disease is a controversial topic, and in my experience iodine needs to be dosed appropriately to provide benefit and prevent harm. Some research has shown that low-dose daily supplementation when combined with thyroid hormone therapy can improve outcomes and reduce thyroid antibody levels. I’ve found that for most people with Hashimoto’s, low-dose iodine supplements (such as in the range of 150–220 mcg, found in multivitamins and prenatal vitamins) are usually safe and potentially helpful.
However, I have received countless messages from people with Hashimoto’s who have tried high-dose iodine (above 500 mcg per day from supplements, seaweed, kelp, or spirulina). Researchers and my readers have reported that these high doses can lead to adverse reactions such as reduced thyroid hormone levels, increased thyroid antibodies, an exacerbation of thyroid symptoms, and even an accelerated destruction of thyroid tissue! Even those who may initially feel “more energetic” while taking a high-dose iodine supplement are often left feeling much worse after some time—this is because the bump in energy is often a result of the destruction of thyroid tissue, which dumps thyroid hormone into circulation!
Certainly I won’t deny that some people with Hashimoto’s have been helped by high-dose iodine. However most feel that the risks outweigh the benefits for people with Hashimoto’s, and I caution people against the use of high-dose iodine. Out of my Root Cause readers who were surveyed, 356 tried high-dose iodine. Out of that group, 25 percent said that high-dose iodine made them feel better, 28 percent said that it made them feel worse, and 46 percent saw no difference in how they felt (although this doesn’t mean that their thyroid markers weren’t affected). The takeaway from this survey is that more people felt worse on high-dose iodine than felt better.
In those who have been exposed to high doses, I may even recommend short-term iodine restriction. Research has shown that a low-iodine diet has been helpful in reducing the autoimmune attack on the thyroid gland and in normalizing thyroid function in people with iodine-induced Hashimoto’s. In my survey, iodine restriction made 31.7 percent feel better and 7 percent feel worse. In this case, a person would temporarily restrict iodine to less than 100 mcg per day for a period of one to three months (the thyroid gland needs approximately 52 mcg per day of iodine, which you’re likely getting if you take thyroid hormone medications). I’m including iodine in the nutrient analysis of the recipes in this book for those who wish to monitor their iodine intake.
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There are a handful of other common myths and questions I hear about food, the thyroid, and Hashimoto’s that I will be addressing throughout this book, as in many cases misunderstood facts can lead to missed opportunities for healing.
SHOULD YOU BE VEGAN OR VEGETARIAN WITH HASHIMOTO’S?
Another question I hear often is whether I recommend a vegan or vegetarian diet for Hashimoto’s. Although research by Seventh-day Adventists suggests that a vegan diet may be protective against thyroid disorders, I have not found the vegan diet to be especially helpful for most of my clients with Hashimoto’s. The research was based on a questionnaire that was deployed to 97,000 Seventh-day Adventist Church members asking them about their dietary habits and health conditions. The study reported that people who followed a vegan diet were less likely to develop hypothyroidism compared to those on the Standard American Diet (a diet high in meat, fat, dairy, refined carbohydrates, and salt). In contrast, people who followed a lacto-ovo vegetarian diet were more likely to develop hypothyroidism compared to those on the Standard American Diet. It’s possible that the reduction in hypothyroidism seen in the vegan diet was due to excluding dairy and eggs, which are two common reactive foods in people with Hashimoto’s.
I’ve also actively sought out success stories from various places to find Hashimoto’s remission stories. Time and time again, I’ve been led to cases of vegan Hashimoto’s remission stories, only to find that, upon deeper investigation, the person continues to struggle with symptoms such as low body temperatures, depression, brittle hair, irritable bowel syndrome, dry, pale skin, and numerous other symptoms correlated with Hashimoto’s.
Another study cited by proponents of the vegan diet noted the connection between antibodies formed to the thyroid and antibodies formed to Neu5Gc, a protein found in mammalian meats like
lamb, pork, and beef. This study, published in 2014, reported that the majority of people with Hashimoto’s present with antibodies to Neu5Gc. However, the study did not attempt to demonstrate if exclusion of mammalian meat made any difference in Hashimoto’s outcomes. In practice, most of my clinical experience points to the fact that people actually improve with the inclusion of mammalian meat.
In surveying my readers, out of 595 people who tried to avoid red meat, 40 percent reported that avoiding red meat made them feel better, while 14 percent reported that avoiding red meat made them feel worse. Only 8 percent saw a reduction in thyroid antibodies with avoidance of red meat.
Clinically, I had not seen a lot of success in people with Hashimoto’s who followed a vegan diet, a vegetarian diet, or a red meat–restricted diet. Additionally, some former vegans have been able to get their Hashimoto’s into remission by transitioning to a Paleo-like diet. In surveying my readers, similar results were reported. Although 30 percent of people felt better while following a vegan diet, 28 percent of people with Hashimoto’s felt worse with this type of diet! In contrast to the gluten-free diet, which has become my gold standard for Hashimoto’s, 88 percent of people with Hashimoto’s feel better gluten free, while less than 1 percent feel worse!
Notably, the vegan diet did show a reduction in thyroid antibodies. As I mentioned, my hypothesis is that the antibody reduction resulted from the exclusion of dairy and eggs, two common reactive foods for people with Hashimoto’s.
Hashimoto’s Food Pharmacology Page 5