How the thyroid effects your weight correction


Most people who convert to low carb experience fantastic health and weight correction. There are however those that find weight correction difficult even when approaching low carb correctly. 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.

Important issues to consider in deciding whether hypothyroidism is contributing to stalled weight or other health problems:

  • Hypothyroid symptoms–Beyond stalled weight loss, the most common symptoms of low thyroid hormone status include cold hands and feet; low energy; mental “fog;” loss of hair and eyebrows; constipation; leg edema.
  • Low first a.m. oral temperature–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 36.2 degrees , 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.
  • Iodine deficiency–Though it’s not even on most people’s radar, iodine deficiency is a common and under-diagnosed 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.

Many people, including physicians, assume that iodine intake from diet is sufficient. Nope. Even the national federally-funded NHANES data have uncovered substantial deficiency in some demographic groups, such as women of childbearing age, using a 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. 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., 50-100 mcg per day, can be introduced and increased gradually over months after wheat/grain elimination and vitamin D has been restored (factors that allow autoimmune thyroid inflammation to recede) . 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 with gradual relief from hypothyroid symptoms (but only if iodine deficiency is the cause). Using a good source of both Vit D and iodine would be cod liver oil and or Moringa daily. 

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. Consistent low carb without iodine and selenium from fish etc has been seen to elevate TSH. This is one of the reasons I recommend the 7th day spike or carb refeed.

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), triclosan in your antibacterial hand soap and hand sanitizer, 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. Its an issue than can be corrected.

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 as well as getting early sun and eating breakfast soon after waking.

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. 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.