Galactosemia is a metabolic disorder that some babies are born with. It's caused by problem with the enzymes that break down the sugar galactose. Babies with galactosemia (geh-lak-teh-SEE-mee-uh) have high levels of galactose in their blood.
Lactose is the main type of sugar in milk, milk-based formulas, and breast milk. Lactose is made up of glucose and galactose. That's why babies with galactosemia can't have milk and dairy products.
There are three types of galactosemia, depending on which enzyme doesn't work. The most common and severe type is called classic galactosemia.
What Are the Signs & Symptoms of Galactosemia?
Signs of classic galactosemia usually start in a baby's first week of life. They include:
Untreated galactosemia can lead to liver damage, kidney failure, and intellectual disabilities. So doctors will put babies with galactosemia on a soy formula (which doesn't contain lactose) as soon as possible. Babies must drink soy-based formula instead of breast milk or a cow's milk-based formula. Milk-based "lactose-free" formulas are not recommended.
Kids with classic galactosemia must continue to keep milk and other dairy products out of their diets. Most will need to take calcium supplements.
Children with milder types of galactosemia might be able to have some dairy. That's because the enzymes that break down galactose are partially working.
What Causes Galactosemia?
Galactosemia happens when there's a change (mutation) in the genes that make an enzyme that breaks down galactose. To have galactosemia, a child must inherit two galactosemia genes, one from each parent.
In galactosemia, galactose and its byproducts build up in the blood. This can damage cells and parts of the body.
What Else Should I Know?
Early diagnosis and treatment can help reverse cataracts, aid growth, and improve liver and kidney problems. Even with good dietary treatment, children with galactosemia may have: