A 55-year-old man is evaluated during a routine examination. He feels well other than mild knee pain. He drinks six to eight cans of beer per night. He has no personal history of liver disease, but his older brother was recently diagnosed with hereditary hemochromatosis.

On physical examination, vital signs are normal; BMI is 24. He is tanned on sun-exposed body surfaces. Cardiac examination is normal. Abdominal examination reveals hepatomegaly. Bilateral bony hypertrophy of the knees is noted.

Laboratory studies:

Alanine aminotransferase

70 U/L

Aspartate aminotransferase

160 U/L

Ferritin

592 ng/mL (592 µg/L)

Transferrin saturation

40%

Genetic testing for hemochromatosis reveals heterozygosity for C282Y. Abdominal ultrasound reveals a change in liver echotexture consistent with fatty changes.

Which of the following is the most appropriate treatment?