Vet ikke om problemet er høy stoffskifte, men tror det kan være noen farer ved for lavt. Nedenfor finner du noe jeg har klipt og for forskjellige kilder på nettet:

Pasienthåndboka:
Enkelte medisinske miljø anbefaler å starte behandling med tyroksin dersom det påvises antistoffer (anti-TPO). Det tilrås samtidig å være forsiktig med å behandle eldre mennesker, fordi tyroksin kan utløse hjerteproblemer.
Medicine Online:
The long-term effects of untreated hypothyroidism can be profound. Severe, prolonged hypothyroidism can lead to multiple abnormalities within any system of the body including heart, brain, and skin. Untreated hypothyroidism can cause heart disease, osteoporosis or thinning of the bones, and infertility in women. Hypothyroidism slows the heart rate and weakens the heart's contractions. If left untreated for many years, severe hypothyroidism can eventually lead to death.
Science Daily:
Even Mild Thyroid Problems Double Risk Of Heart Condition.
The Cardiovascular Health Study involved over 3,000 adults 65 years and older, who were evaluated to determine if those individuals who had subclinical hypothyroidism had an increased risk of developing heart failure over a twelve-year period. The study shows that individuals who had a TSH level equal or greater than 10 mU/L had a two-fold risk of developing heart failure, compared to those who had normal thyroid levels.