Amyotrophic lateral sclerosis (ALS), often referred to as Lou Gehrig’s disease, is a debilitating neurological disorder that gradually damages neurons in the brain and spinal cord. This progressive destruction leads to paralysis, ultimately impairing a person’s ability to breathe.

Currently, there is no known cure for ALS, and the prognosis is grim, with most patients facing a life expectancy of two to five years following diagnosis.

Tragically, Eric Dane, the actor renowned for his portrayal of ‘McSteamy’ on Grey’s Anatomy, succumbed to ALS last week at the age of 53, less than a year after revealing his battle with the disease.

The precise cause of ALS remains elusive, with researchers pointing to a complex interplay of genetic factors, age, environmental exposures, and lifestyle habits as potential contributors.

In a promising development, scientists have identified two lifestyle factors that may lower the risk of developing this fatal condition.

Preliminary findings from a study set to be presented at the 78th Annual Meeting of the American Academy of Neurology in April suggest that early risers and individuals who engage in regular physical activity face a reduced risk of ALS.

The study included 500,000 people and compared early birds to ‘night owls’ – people more productive later in the day. 

It found that productivity earlier in the day was associated with a 20 percent lower risk of ALS compared to people who were night owls. 

Eric Dane is pictured above, right, in Grey’s Anatomy in 2006, and pictured above, left, in October 2025. The actor announced his ALS diagnosis earlier that year

Additionally, the research found a 26 percent lower ALS risk among people who were more physically active compared to those less active. 

Study author Dr Hongfu Li of Zhejiang University in China said: ‘Previous research suggests better sleep and more physical activity may reduce the risk of some neurodegenerative diseases, but results for ALS have been mixed.

‘Our study found a sleep schedule that better matches daylight hours and more physical activity were related to a lower risk of ALS.’

Researchers noted that a causative link was not established between not following these habits and developing ALS, rather results show an association. 

The researchers followed the half a million participants, who had an average age of 57, for 14 years. During this time, 675 people, 0.14 percent, developed ALS.

In the US, about 6,000 new cases of ALS are diagnosed per year, about two per 100,000 people. There are approximately 36,000 people currently living with ALS and 6,000 people die a year from the disease in the US.

Participants completed questionnaires at the start of the study about their sleeping and physical activity habits. 

Researchers then analyzed the habits of people who fell into two sleep chronotypes – a person’s natural preference for waking and sleeping: morning, ‘early bird,’ and evening, ‘night owls.’

Morning chronotypes reported a preference for earlier bedtimes and wake times and had peak productivity earlier in the day.  Evening chronotypes preferred later bedtimes and wake times and had peak productivity later in the day.

Astrophysicist Stephen Hawking, pictured above in 2007, died in 2018 at 76 years old after battling ALS

The preliminary study did not specify exact timings for each chronotype. 

The protective factor of being an early bird existed even after researchers adjusted for age, sex and body mass index. 

They also found that people who slept between six and eight hours a night had a lower risk of ALS than people who got more or less sleep. 

To study the relationship between exercise and ALS risk, researchers used metabolic equivalents (METs). METs compare energy of various activities to energy expended during one hour of inactivity.

For each physical activity participants reported in the study, the METs were multiplied by the frequency and duration; this gave a score of METs-minutes per week. 

Vigorous activities such as running and cycling were classified as eight METs; moderate-intensity activities like carrying light loads and household activities were classified as four METs; and lower-intensity activities such as walking were classified as 3.3 METs. 

The average physical activity level for participants in the study was 2,645 METs-minutes per week.

Researchers found that among those who had more physical activity, 600 MET-minutes or more per week, 386 of 314,170 people developed ALS. Among those who had less, 107 of 70,946 people developed ALS.

After adjusting for age, sex and body mass index, 600 MET-minutes or more per week was associated with a 26 percent lower risk of ALS.

Li said: ‘While more research is needed to further explore these associations, promoting healthy lifestyle behaviors may represent a potential strategy for reducing the risk of ALS.’

Researchers also noted that a study limitation was that 95 percent of participants were white, meaning the results may not translate to other races or ethnicities.