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When food intake is reduced, the body increases an enzyme called D3 in key metabolic tissues, which breaks down the active thyroid hormone, slowing metabolism to conserve energy during periods of low...
Some people inherit a slightly different version of the D2 enzyme that works less efficiently, and this is linked to a higher chance of developing insulin resistance and type 2 diabetes, though not...
When oxygen levels are low, cells produce an enzyme called D3 that shuts down the active form of thyroid hormone, slowing down metabolism to conserve energy and shift toward less oxygen-dependent...
In fat, muscle, and liver cells, the enzyme D2 converts the thyroid hormone T4 into the more active T3 when triggered by signals like cold or insulin. This increases the cells' metabolic rate and...
Even though the body cleared thyroid hormone T4 faster or slower depending on how much the pigs ate, the actual amount of hormone in their blood stayed the same, suggesting the body adjusts how much...
Researchers noticed that how the body processed thyroid hormone T4 changed over time depending on how much the pigs ate, and they suggested this might mean tissues became more or less responsive to...
Unlike T4, the rate at which the body clears the thyroid hormone T3 did not change significantly in pigs regardless of whether they ate a lot or a little over six weeks, indicating T3 metabolism is...
Pigs eating more initially broke down thyroid hormone T4 faster, but after four weeks, pigs eating less broke it down faster instead, showing that how the body handles this hormone changes over time...
Pigs that ate less over six weeks had a lower resting metabolic rate and could tolerate colder temperatures before needing to warm up, while pigs that ate more had a higher resting metabolic rate and...
Levels of the hormone leptin rise in the second half of the menstrual cycle, but this rise does not explain why the body burns slightly more calories at rest during that time, indicating leptin is...
Women taking combined birth control pills do not show a consistent change in the number of calories burned at rest between the active pill days and the placebo days, unlike women who menstruate...
Women who menstruate naturally tend to consume about 13 more grams of fat per day during the second half of their cycle compared to the first half, which may reflect a natural shift in appetite or...
In women who menstruate naturally, levels of the thyroid hormone T3 rise in the second half of the cycle, and this increase is linked to a small rise in the number of calories burned at rest, even...
In women who menstruate naturally, the body burns about 40 to 44 extra calories per day during the second half of the menstrual cycle compared to the first half, likely due to changes in hormone...
People taking synthetic thyroid hormone (T4) for hypothyroidism show a small increase in the amount of active hormone (T3) made from T4 in their tissues, but this increase is not large enough to be...
When people are seriously ill but their thyroid gland is functioning normally, their bodies convert less of the inactive thyroid hormone (T4) into the active form (T3) in tissues outside the thyroid....
In healthy people, most of the active thyroid hormone in the blood comes from the conversion of a precursor hormone in tissues outside the thyroid gland, not from the thyroid gland itself. This...
In adults with type 2 diabetes, most cases of mild thyroid dysfunction are caused by an autoimmune condition (evidenced by anti-TPO antibodies), but having these antibodies does not increase the risk...
In adults with type 2 diabetes, overactive thyroid without symptoms (subclinical thyrotoxicosis) is very uncommon—fewer than 1 in 500 people—and there are too few cases to determine if it affects...
In adults with type 2 diabetes, very low or very high levels of free thyroxine (FT4) are linked to higher death rates, but these findings are based on very few people, so they may not apply to most...
Among adults with type 2 diabetes, those with mildly elevated thyroid-stimulating hormone (TSH) levels tend to have higher blood pressure and reduced kidney function, even after accounting for age...
Among adults with type 2 diabetes, having a mildly elevated thyroid-stimulating hormone (TSH) level above 5.1 mIU/L does not increase the risk of heart attacks, strokes, or death over nearly seven...
After three months of thyroid hormone treatment, children with underactive thyroids see their heart's electrical recovery time improve, but their heart rate variability remains unchanged, indicating...
Children with underactive thyroids do not show measurable changes in their heart's autonomic control, even though their heart's electrical recovery time is delayed, indicating that these two effects...