Taking thyroid hormone at bedtime raises levels better BUT...

A study just published in the Archives of Internal Medicine presents evidence that taking levothyroxine (T4, thyroid hormone) before bed raises levels more effectively. But it also illustrates the important practical point that it still doesn't help most patients to feel better anyway (because of the autoimmune dynamics of most hypothyroid cases). The authors state:

"There is consensus that levothyroxine should be taken in the morning on an empty stomach. A pilot study showed that levothyroxine intake at bedtime significantly decreased thyrotropin levels and increased free thyroxine and total triiodothyronine levels...To ascertain if levothyroxine intake at bedtime instead of in the morning improves thyroid hormone levels, a randomized double-blind crossover trial was performed."

Patients at Maasstad Hospital Rotterdam in the Netherlands took a capsule in the morning and at bedtime. One was levothyroxine and the other placebo. After three months the capsules were 'reversed'. The authors followed thyroid hormone levels, creatinine, lipids, body mass index, heart rate, and quality of life. What did the data show?

"Ninety patients completed the trial and were available for analysis. Compared with morning intake, direct treatment effects when levothyroxine was taken at bedtime were a decrease in thyrotropin [TSH, due to increase thyroxine] level of 1.25 mIU/L, an increase in free thyroxine level of 0.07 ng/dL, and an increase in total triiodothyronine level of 6.5 ng/dL."

BUT...

"Secondary outcomes, including quality-of-life questionnaires (36-Item Short Form Health Survey, Hospital Anxiety and Depression Scale, 20-Item Multidimensional Fatigue Inventory, and a symptoms questionnaire), showed no significant changes between morning vs bedtime intake of levothyroxine."

The authors concluded:

"Levothyroxine taken at bedtime significantly improved thyroid hormone levels. Quality-of-life variables and plasma lipid levels showed no significant changes with bedtime vs morning intake."

Why? Because most hypothyroid in developed countries is autoimmune in nature. The background inflammatory activity impairs thyroid receptor function and upregulation of the relevant genes. For those interested in the functional medicine approach to thyroid conditions see Dr. Kharrazian's Why Do I Still Have Thyroid Symptoms under Useful Links on the right.