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When given a hormone that stimulates the thyroid, sick elderly patients with low T3 produce more T3 than expected and less T4, which helps normalize the balance between these hormones — indicating...
In sick elderly patients, a related thyroid hormone called reverse T3 is often higher than normal, but this increase doesn't always happen when T3 is low — meaning other factors besides reverse T3...
In older adults who are sick and hospitalized but have normal thyroid function, the active thyroid hormone T3 is lower than in healthy younger people, while the inactive precursor T4 is higher,...
People who started taking thyroid hormone medication more than a year after having half their thyroid removed still had a 73% lower risk of dying than those who never took it, indicating that even...
People who had their entire thyroid removed for a non-cancerous condition and took thyroid hormone medication afterward had no higher risk of dying than the average person in Sweden.
People who had half their thyroid removed for a non-cancerous condition and did not take thyroid hormone medication afterward were 31% more likely to die than the average person in Sweden during the...
Among people who had part of their thyroid removed for a non-cancerous growth, those who took higher daily doses of thyroid hormone medication had a lower risk of dying during follow-up, with each...
People who had part of their thyroid removed for a non-cancerous growth and did not take thyroid hormone medication afterward were 65% more likely to die during the follow-up period than those who...
When thyroxine is injected into the fluid around a human fetus, the fetus takes it up into its bloodstream, leading to detectable changes in thyroid hormone levels. This finding is from the abstract...
Even when a fetus is exposed to high levels of thyroxine through amniotic fluid injection, the newborn's thyroid-stimulating hormone still rises after birth, suggesting the fetal thyroid system does...
When thyroxine is injected into the amniotic fluid surrounding a human fetus, the fetus converts some of it into reverse T3, but not into active T3 hormone, indicating a specific pattern of thyroid...
Even though T3 improves resting heart energy in hypothyroid sheep, it does not help the heart maintain energy levels when it's working harder, such as during stress or exercise.
In sheep with normal thyroid function, a dose of T3 hormone does not change the heart's energy state, indicating that the hormone only improves energy efficiency when the body is already low in...
T3 improves heart energy efficiency in hypothyroid sheep not by changing how mitochondria swap ADP and ATP, but likely by altering which fuel sources the heart uses, such as increasing fat burning...
T3 hormone does not directly improve how heart cells swap ADP for ATP at the mitochondrial membrane, even in animals with low thyroid hormone levels, ruling out this mechanism for its observed energy...
In sheep with underactive thyroids, a single dose of T3 hormone rapidly improves the heart's energy efficiency by increasing stored energy molecules and reducing a key energy-use signal, without...
In rats with artificially high thyroid hormone levels, the heart mitochondria increase one key antioxidant enzyme (superoxide dismutase) but do not change another (catalase), indicating a targeted...
In rats with artificially high thyroid hormone levels, the mitochondria in heart cells become less efficient at converting oxygen use into energy, requiring more time to produce ATP and showing...
In rats with artificially high thyroid hormone levels, heart mitochondria generate more harmful reactive molecules, damage fat molecules in cell membranes, and reduce key antioxidant defenses,...
In rats with artificially high thyroid hormone levels, the mitochondria in heart cells show increased activity in some energy-producing complexes but decreased activity in others, while the total...
Giving rats high doses of thyroid hormone for seven days causes their hearts to grow larger and increases the levels of thyroid hormones in their blood, mimicking a condition known as hyperthyroidism.
In obese mice, giving T3 led to higher levels of T3 and lower levels of T4, suggesting the body reduced its own thyroid hormone production in response. This finding is from the abstract summary -...
In obese mice, giving the thyroid hormone T3 was linked to lower levels of another thyroid hormone (T4), insulin, and blood sugar, while muscle and other lean tissues stayed the same. This finding is...
In a specific strain of obese mice, daily injections of the thyroid hormone T3 for three weeks were linked to higher energy use, warmer body temperature, and less body fat, while muscle and other...