Hypothyroidism, Metabolism and Food Intake

18 newly diagnosed hypothyroid female patients and 18 healthy controls age between 20 and 75 years will be recruited from the out-patients clinic in Herlev and Gentofte Hospital and the general practitioners before start of substitution therapy.

The study is devided in to three identical experimental days of approx. 6 hours. First experimental day placed before T4 treatment is initiated. Second day as soon as Thyroid Stimulating Hormone (TSH) is below 4 milli unit pr liter (mU/l). The Third experimental day after 6 months of T4 therapy.

For 5-7 days before each experimental day, the participants' physical activity energy expenditure (PAEE) will be monitored by an Actiheart® pedometer attached to the skin of the chest.

The last two days before each experimental day, the participants will follow a standardised diet following World Health Organization guidelines on energy requirements and nutrient composition according to gender, age and body weight Shortly after diagnosis patients will undergo a test panel at the first experimental day, where patients arrives fasting.

Visual analog score on satiety and thirst will be filled out continuously. REE will be measured by a CCM-express calorimeter,

• Dual Energy X-ray absorptiometry (DEXA)-scan
• Blood samples will be taken continuously during the experimental day. Gall bladder size will be examined at 6 times during the experimental day using ultra sound.

At the end of the day, patients´ satiety will be examined with an ad libitum meal.

Blood will be analysed for Gastric inhibitory polypeptide (GIP), Glucagon-like Peptide 1 (GLP-1), Glucagon-like Peptide 2 (GLP-2), glucagon, peptide tyrosine tyrosine (PYY), Gastrin, Cholesystokinin (CCK), Insulin, C-peptide, Blood sugar, Cholesterol, Free fatty acids and paracetamol.

Inclusion criteria

• TSH > 10
• Female

Exclusion criteria

• Competing serious disease
• Male
• Not able to understand written and spoken danish
• Pregnancy
• Thyroidectomized patients
• Amiodarone treatment.