Imagine that all the cars in your neighborhood run poorly because nobody bothers to tune-up their autos. I show you how to tune your car and, lo and behold, 80% of the cars now run great. But 20% of cars still run poorly because their transmissions are bad. In other words, tuning the engine works when that’s the only problem with the car; if something else is wrong, then you car will not run properly.
So it goes with eliminating wheat from the diet. It works for the majority of people: substantial weight loss and shrinking waist size; reduced blood sugar and blood pressure; relief from arthritis, leg edema, acid reflux, irritable bowel syndrome symptoms, etc. But some people complain that, despite saying goodbye to all things wheat, they still have problems. Obviously, as big a problem as modern wheat is, there are other causes for health conditions besides wheat consumption. There are infections, injuries, sensitivities to other foods, inherited conditions, etc. While wheat exposure is a cause for an incredible amount of human suffering, it is not the only cause.
How about weight loss? If all things wheat are eliminated, most people can expect substantial weight loss. Some people will also need to reduce exposure to other carbohydrates, especially if a lot of body weight needs to be lost and/or pre-diabetic or diabetic patterns are established. We cannot say “eliminate wheat and eat all the ice cream and candy you want.”
Then there are people who do all that and still cannot lose weight. This is when it’s time to give serious consideration to thyroid dysfunction.
By “thyroid dysfunction” I am referring to various degrees of hypothyroidism, i.e., low thyroid hormone levels. (I’m going to ignore hyperthyroidism, since this is much less common and does not impose any limitation on weight loss.) This is a big issue, so I’m going to cover it as a check list, a series of bullet points that you can run down to cover as much territory as possible. There are three blood tests that everyone should have assessed to even start thinking about thyroid dysfunction: TSH (thyroid stimulating hormone), free T3, and free T4. Optionally, a reverse T3 and thyroid antibodies (to identify thyroid inflammation/autoimmunity) can also be helpful. You do not need all the other nonsense often run, such as total T3 and FTI; these are outdated and often misleading.
Important issues to consider in deciding whether hypothyroidism is contributing to stalled weight:
Hypothyroid symptoms–Beyond stalled weight loss, the most common symptoms of low thyroid hormone status include cold hands and feet; low energy; mental “fog;” increased loss of hair and eyebrows; constipation; leg edema.
Low first a.m. oral temperature–While not validated in clinical trials, anecdotally an oral temperature immediately upon awakening can help you decide whether a thyroid question is present or not. Using a digital thermometer, take your oral temperature immediately upon arising. If it is consistently below 97.3 degrees F, then hypothyroidism is likely; the lower the temperature, the more likely and severe the thyroid dysfunction. However, note that disruptions of cortisol can do the same. (Contrary to some older discussions from the 1960s, axillary temperature should not be used due to excessive variation.)
Iodine deficiency–Though it’s not even on most people’s radar, iodine deficiency is a common and underdiagnosed cause for inadequate thyroid hormone production. The thyroid requires iodine to manufacture thyroid hormones, T3 and T4, the “3″ and “4″ referring to the number of iodine atoms per thyroid hormone molecule. Iodine deficiency was a huge public health issue up to the last half of the 20th century, pretty much solved by the introduction of iodized salt. Now that salt overexposure in some populations has been fingered as a potential health problem, the FDA and other “official” providers of health advice tell us to reduce salt and sodium. But what about the iodine? Everyone forgot about the iodine.
Many people, including physicians, assume that iodine intake from diet is sufficient. Nope. Even the NHANES data have uncovered substantial deficiency in some demographic groups, such as women of childbearing age, using their relatively lax definition of iodine deficiency. I’m seeing iodine deficiency and even goiters (enlarged thyroid glands due to iodine deficiency) frequently. Beyond having a goiter, a low free T4 and highish TSH (e.g., 3.5 mIU) is suggestive of iodine deficiency.
Iodine is not optional; it is necessary for health, including breast health, oral/gastrointestinal health, and the health of a developing fetus. The RDA for non-lactating adults is 150 mcg per day, the quantity required to not have a goiter, but not necessarily ideal thyroid health. I’ve therefore been advising 500-1000 mcg per day from an iodine supplement, such as kelp tablets (dried seaweed), available at health food stores (not pharmacies). The only adverse effects of iodine arise in people who have inflammatory thyroid disease, such as Hashimoto’s thyroiditis, unsuspected thyroid nodules, or longstanding and severe iodine deficiency. In most cases, very low doses of iodine, e.g., 100 mcg per day, can be introduced and increased gradually over months. (Ideally, this would be undertaken by your healthcare provider, but good luck finding one knowledgeable about iodine.)
For most people, restoration of iodine usually develops over 3-6 months.
Ideal TSH–Notice I didn’t say “normal” or “reference range” TSH. I look for ideal TSH. Contrary to the values often cited as “normal” or “reference range” on laboratory values, ideal TSH is in the range of 1.5 mIU or less. This is the level at which thyroid dysfunction no longer contributes to stalled weight loss, as well as distortions of lipid (“cholesterol”) values and cardiovascular risk. The higher the TSH above 1.5, the greater the hypothyroidism.
Ideal free T3 and free T4–The upper half of the “reference range” quoted by your laboratory can serve as a reliable guide to desirable or ideal levels of these thyroid hormones. In particular, low free T3 levels are becoming a common problem and a frequent cause of stalled weight loss. It is not clear why T3 levels are impaired, but potential explanations include disturbed circadian variation of cortisol levels and exposure to organochemicals such as perchlorates (residues of synthetic fertilizer in your produce and water) and others. Unfortunately, the endocrinology community (which is woefully unhelpful with thyroid issues except in the most severe cases) sooner prescribe antidepressants than treat low T3 levels, which they regard as a non-issue. (I had low T3 personally with normal TSH and free T4, along with flagrant symptoms of hypothyroidism and a body temperature of 94.6 F, all corrected with thyroid hormones that included T3.)
Reverse T3–Less commonly, some people develop a T3 thyroid hormone mimic, reverse T3, or rT3, that blocks the activity of T3 in the body. In this situation, it is worth more seriously considering disrupted circadian cortisol variation and using higher doses of T3 thyroid hormone to overcome the blockade.
Should prescription thyroid hormone replacement be chosen, most people do best by including the T3 thyroid hormone, liothyronine, along with T4, levothyroxine. They can be taken separately and as a single tablet in desiccated thyroid gland preparations like Armour thyroid and Naturethroid. Alternatively, if you already take a T4 preparation like Synthroid or levothyroxine but have stalled weight loss or persistent symptoms of hypothyroidism, then adding T3 nearly always solves the problem.
Unfortunately, the biggest hurdle in obtaining helpful feedback on your thyroid is usually your doctor, who will declare your thyroid status normal usually by just looking only at TSH and seeing whether it is in the “reference range” quoted by the laboratory–if he/she even bothers to check it at all. Lately, the naturopath community has been very helpful to many people in my area eager to have their thyroid status intelligently assessed. As a last resort, you can purchase fingerstick test kits to obtain thyroid measures, such as the ZRT test kits we make available in my Track Your Plaque heart disease prevention program.
Once properly corrected, the majority of people enjoy resumption of weight loss, not to mention feel happier, more energetic, with improved overall health, including reduced cardiovascular risk. Add that to the health and weight benefits of wheat elimination, and you can make substantial strides in regaining ideal health.




William Davis, MD, is a preventive cardiologist whose unique approach to diet allows him to advocate reversal, not just prevention, of heart disease.
He is the founder of the 

Dear Dr. Davis – I am a 37 yr old female who had a partial thyroidectomy 18 months ago. It took me 9 months to convince my doctor to put me on a thyroid replacement (levothyroxine) even though I was exhibiting clear hypo symptoms and went up 2 clothing sizes in a very short period after my surgery. In January of this year, after reading Wheat Belly, I saw some progress losing 10 pounds and one clothing size in about a month, but then I seemed to crash. Right back to the slugishness, dizziness, weight gain, no energy and now I’ve gained back all the weight and am right back where I started. My endocrinologist just bumped up my levothyroxine dose to 3.75 mcg, but I’m still not feeling any better. Also, they are really only focused on my TSH levels and keeping it just under 3. I don’t care for my endocrinologist – don’t think she listens, or is in tune with any of the recent thyroid care guidelines. I am intrigued by the information in your blog about thyroid (especially the T3 supplementation and keeping TSH levels closer to 1.5), but don’t think my endo would even remotely listen to it. I live in the Milwaukee area and was wondering if you had any recommendations for a Milwaukee area doctor who is more on your plane of thinking when it comes to thyroid treatment? I’d be grateful for any suggestions! Thanks! Angie H.
Hi, Angie–
Good news: the solution is incredibly simple. It means just paying attention to your T3 status, not just T4 (levothyroxine).
Bad news: Endocrinologists are the Monsanto of healthcare. If you want insight into thyroid and endocrine disorders, the last specialist to consult is an endocrinologists, experts at nothing more than booby trapping and impairing health.
Functional medicine docs or naturopaths are your most confident solutions. Dr. Glenn Toth in Waukesha, Dr. Carol Brown in Oak Creek, Dr. Deb Muth in Delafield, and Dr. Michelle Nickels in Brookfield are among your best bets.
Dr Davis,
I appreciate your book confirming my thought on the wheat industry, also Endo MD’s as the Monsanto of medicine. I have Hasimoto’s autoimmune thyroid aswell asantibosies for Grave’s disease. In addition I was recent;y diagnosed with a severeform of Celiac disease and a positive MTHFR mutation. I take methylfolate
and am intrigued by your findings. The big issue I have is I am a gluten-free vegan with high antibodies to casein. I need advise on wheat free,grain free but beans and legumesare typically my source of protein in addition to green vegetables. Will this impede the weight loss? Incidentally, my Endo doesn’t treat TSH unless it’s greater then 5!!! I thankfully see a Functional Medicine MD who is planning to prescribe Armour
after my biopsies of nodules are complete in June. Please advise on the vegan protein source and weight loss.
Hi, Patti–
You will have to compromise by maximizing protein intake from the legumes. Of course, nuts, seeds, including chia, need to play a prominent role. Because you are so limited, non-GMO soy consumed in modest portions, I believe, is a good thing.
Thanks Dr Davis for the additional advise. One more question, how do you feel about fish as a protein source? Having the restrictions that I do, I have revisited the re-addition of seafood as an additional protein source. At one point in your book you mentioned different effects of dairy, some having a lesser “animal protein” infamm.response, especially aged cheeses due to the fermentation process. As well the need to avoid the other dairy – milk, cream cheese, cottage cheese, etc. for the opposite reason. Would that apply even with antibodies present to casein, as in my case? Does fermentation effect the lactose or casein/whey effect? Your book has been a real treat, .Lots of info, not overly simplistic yet concise and factual. I am an ICU/Trauma nurse so I appreciate your writings, it restores a small amount of my faith in the healthcare industry. Being employed at a large, cardiac -centered medical campus in Cleveland, the conventional food pyramid is STILL used.
Dr. Davis, I have not yet gotten around to reading your book, but cut out wheat (only) for the past week and feel a lot of puffiness, mental fatigue and “constantly having to go” is gone. I am about to have a physical and would like to raise the topic of thyroid issues (which run in my family) – an alternative practitioner put me on huge(!) doses of iodine a while back. I don’t want to go back to him, as I very much question some other decisions he has made. Can you recommend someone to see in Tennessee?
Thank you, and thank you for your very thought-provoking book (next on my reading list)!