Sub-clinical hypothyroidism is characterized by a shortage of the hormone thyroxin and often precedes an underactive thyroid. It affects up to 16% of women and 6% of men; it becomes more prevalent with age.
The Newcastle team, led by Dr Jolanta Weaver, has shown that treatment of sub-clinical hypothyroidism with thyroid hormone reduces tiredness, lowers cholesterol and cuts the risk of heart disease by improving the markers of atherosclerosis or hardening of the arteries.
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I have a new excuse now :)