You can technically develop ALS at almost any age, but it’s most common between 40 and 70 , with the average age around 55.

Typical age range

  • Most diagnoses happen between ages 40–70.
  • The average age at diagnosis is about 55.
  • ALS becomes more common as people get older, especially into their 60s and 70s.

Can younger people get ALS?

  • ALS can occur in adults of almost any age, including people in their 20s and 30s, though this is uncommon.
  • A very small percentage (about 1%) develop what’s called “juvenile” ALS, with onset before age 25.

Familial vs sporadic ALS

  • Most ALS cases are “sporadic” (no clear family history) and usually start around ages 58–63.
  • “Familial” ALS (runs in families) tends to start earlier, often in the late 40s or early 50s, with onset on average about 5 years younger than sporadic ALS.

If you’re worried about symptoms

If you or someone you know has ongoing muscle weakness, twitching, problems with speaking, swallowing, or walking, it’s important to see a doctor—ideally a neurologist—rather than trying to self-diagnose. Many other, more treatable conditions can cause similar symptoms, so getting checked is the safest next step.

Information gathered from public forums or data available on the internet and portrayed here.