Multiple Sclerosis (MS), an incurable disease that progressively attacks the brain and spinal cord, is reportedly on the rise, particularly among younger demographics. Between 2000 and 2020, the number of MS patients in the UK nearly doubled, from under 100,000 to 190,000, with an annual increase of around six percent. Doctors are observing a concerning trend of more diagnoses in children and teenagers, which, while partly attributable to improved scanning technology and awareness, cannot fully explain the surge, leading experts to pinpoint potential environmental and lifestyle triggers.

Professor Ruth Dobson, a consultant neurologist at Queen Mary University London, emphasizes that while earlier diagnoses and longer patient lifespans contribute, these factors alone do not account for the rising incidence. She suggests that changes in our environment might be responsible and understanding these could lead to prevention strategies. MS occurs when the immune system erroneously attacks myelin, the protective coating around nerves, leading to damage in the brain and spinal cord. It typically develops between ages 20 and 40 and is nearly three times more common in women, for reasons yet unclear. Early symptoms include vision problems, muscle weakness, numbness, fatigue, bladder changes, electric-shock sensations, and dizzy spells, which can fluctuate or worsen over time. While immune-suppressing medication can slow progression, there is no cure. Advanced stages can lead to paralysis, blindness, loss of bladder control, and increased risk of infections, potentially reducing life expectancy by five to ten years.

There are several types of MS. The most common is relapsing-remitting MS (RRMS), characterized by symptom flare-ups followed by periods of remission. This can evolve into secondary progressive MS, where symptoms steadily worsen. Approximately a tenth of patients suffer from primary progressive MS, an aggressive form with continuous worsening symptoms without remission. The reasons for developing one form over another remain unknown.

Recent breakthroughs have shed light on potential causes. The strongest evidence links MS to the Epstein-Barr virus (EBV), a common infection causing glandular fever. Landmark 2022 research found that individuals contracting EBV are at least 32 times more likely to develop MS, as it appears to prime the immune system. Pharmaceutical companies are now developing EBV vaccines in hopes of preventing MS. Another suspected trigger is Vitamin D deficiency. This substance, which behaves like a hormone, helps regulate the immune system and control inflammation. Studies have shown a correlation between low Vitamin D levels and a higher risk of MS, though whether supplements can prevent the disease remains inconclusive, with some research suggesting protection might come from other sunlight factors like UV rays.

Smoking is also strongly linked to MS, potentially doubling the risk by disrupting the immune system in the lungs and weakening the blood-brain barrier, allowing rogue immune cells to inflict damage. However, these three factors – EBV, Vitamin D, and smoking – do not fully explain the recent rise, as EBV infection rates have been stable, sunlight levels consistent, and smoking rates have declined in Britain since 2000.

Researchers are exploring other factors. Childhood obesity, which rose sharply from 11 percent in 1995 to 22 percent today among 8-10 year olds, is a significant concern. Obese children are twice as likely to develop MS later in life, possibly due to the strain excess weight puts on the immune system. Professor Dobson notes a particularly high risk for obese adolescents who also contract glandular fever. The increasing consumption of ultra-processed foods (UPFs) – which constitute over half of British calorie intake – is another area of intense research. While early, evidence suggests that a high UPF diet can impair immune system functioning, potentially raising MS risk.

Perhaps most intriguingly, the rise in vaping is being investigated as a new MS trigger. With 5.4 million vapers in the UK, and usage tripling among 11-17 year olds in the past three years, concerns are mounting. Both smoking and vaping disrupt the immune system. While vaping is considered safer than smoking for lung cancer and COPD, the MS Trust and Professor Dobson suggest it could be equally detrimental to the blood-brain barrier and lung lining cells, thereby increasing MS risk by priming the immune system.

Despite the rise, MS remains relatively rare, affecting fewer than one in 400 people in the UK. Even with a strong family history, the chances of developing it are low. Effective drugs now exist to slow MS, especially if caught early. For those concerned, preventative steps include quitting smoking, adopting a healthy diet low in ultra-processed foods, avoiding vaping, and taking a normal-strength daily Vitamin D supplement if needed. These measures, while not guaranteeing prevention, are suggested by research to help reduce the risk.

Becky Lee's story illustrates the disease's insidious onset. At 21, she experienced dizzy spells, indigestion, and muscle spasms, initially diagnosed as clinically isolated syndrome (CIS) – a condition that often precedes MS. Her symptoms worsened, leading to visual disturbances and left-side weakness. In February 2023, after eight years, Becky was diagnosed with relapsing-remitting MS. She now manages the disease with monthly injections of ofatumumab, acknowledging the unpredictable nature of flare-ups but choosing to focus on living her life as best as possible.