Amyotrophic lateral sclerosis (ALS) is a serious neurodegenerative disease, and in most people we do not know the exact cause; you generally don’t “catch” it like an infection, and in many cases it appears to arise from a mix of genetic susceptibility and other, still-unclear factors.

Quick Scoop: What is ALS?

ALS (also called Lou Gehrig’s disease) is a condition where motor neurons, the nerve cells that control muscles, gradually die off. Over time this leads to:

  • Muscle weakness and wasting.
  • Trouble walking, using hands, speaking, and swallowing.
  • Eventually, breathing muscles are affected.

It is progressive, meaning symptoms steadily worsen over months to years.

“How do you get ALS?” – Causes and Risk

For most people, there is no single clear “cause,” but doctors group ALS roughly like this.

  1. Sporadic ALS (most cases)
    • Makes up the vast majority of ALS diagnoses (often quoted around 90% in medical discussions, though exact percentages vary by source).
    • No known family history.
    • Thought to result from a combination of subtle genetic variants plus environmental or lifestyle factors, but no single trigger has been proven for most people.
  1. Familial ALS (inherited forms)
    • A smaller fraction of cases run in families and are linked to specific gene mutations (for example, SOD1, C9orf72 and others in medical literature).
    • In these families, ALS can be passed down from generation to generation, and relatives may have the option of genetic counseling and testing.
  1. What ALS is not
    • Not known to be contagious; you can’t “catch” ALS from being around someone who has it.
    • Not caused by casual injuries, exercise, or single stressful events, although people often search for a trigger after diagnosis.
    • Not currently linked to one universally accepted environmental cause, even though research continues to look at things like toxins, head trauma, military service, and other exposures.

Because of this, when people ask “how do you get it,” the honest medical answer is usually: for most patients, we don’t fully know yet.

Current Research and “Latest News” Angle

In 2025–2026, a lot of work is going into understanding why ALS happens and how to treat it better.

  • Large research collaborations are collecting data and samples from many people with ALS to search for biological patterns and risk factors.
  • Drug development is active: multiple medicines have been approved in recent years in places like the U.S. and Europe, though none is a cure yet.
  • New lab models and drug combinations are being tested to see if they can slow or change the course of sporadic ALS, the common form without clear family history.

Researchers are specifically trying to untangle:

  • Which genes increase risk and how they interact.
  • What environmental exposures might contribute.
  • Why motor neurons are so vulnerable compared with other nerve cells.

So the “how do you get it?” question is exactly what many big research programs are focused on right now.

If You’re Worried About Yourself

If you or someone close to you is having symptoms (such as unexplained muscle weakness, twitching, or trouble speaking or swallowing), the right next step is not to self-diagnose, but to:

  1. See a primary care doctor or general practitioner.
  2. If needed, they can refer you to a neurologist, ideally one with experience in motor neuron diseases.
  3. Ask about:
    • A full neurological exam.
    • Appropriate tests to rule out more common, treatable causes of similar symptoms.

ALS is rare compared with many other conditions that can cause weakness or tingling, so doctors usually rule out other possibilities first.

Support and Reliable Information

If this topic is personal, it may help to connect with:

  • Reputable ALS information sites with sections on “newly diagnosed” and causes, symptoms, and treatments.
  • Patient and caregiver forums or support communities, where people share experiences and practical advice in a moderated setting.

These can offer both medical information and emotional support, which often matter equally when ALS is part of the conversation.

TL;DR: You don’t typically “get” ALS from a single cause or from another person. Most cases are sporadic, with no clear trigger, and a smaller portion are inherited through specific genes; research in 2025–2026 is heavily focused on figuring out those underlying causes and improving treatments.