MS doesn’t just affect nerves — it can affect your smile too.

Oral health isn’t usually the first thing people think about when discussing Multiple Sclerosis — but it should be.Research shows that people with MS are more likely to develop gum disease, dry mouth, tooth sensitivity, and difficulty performing daily oral-care routines. Not because of poor habits, but because MS affects the body systems needed for proper oral hygiene: motor control, coordination, saliva production, energy levels, and even inflammation.

This article explains why oral health can become more challenging with MS, the mechanisms behind it, and practical strategies that actually help.

1. MS Affects the Muscles You Use for Brushing & Flossing

Brushing and flossing are surprisingly complex motor tasks — they require steady grip strength, fine coordination, and consistent arm movement.But MS can interfere with:

Muscle weakness is one of the most common — and often most confusing — symptoms of multiple sclerosis. People frequently describe their weakness as unpredictable: feeling strong in the morning but unable to lift a leg, climb stairs, or hold objects just a few hours later. This inconsistency isn’t imagined. It’s neurological.

MS affects the communication system between the brain, spinal cord, and muscles. When those signals are slowed, interrupted, or fatigued, strength changes — sometimes dramatically and without warning.

This article explains why muscle weakness happens in MS, how it typically shows up, and what actually helps based on neuroscience, rehab science, and real patient experience.

Why Muscle Weakness Happens in MS

Muscle weakness in MS is rarely caused by the muscle itself. It is almost always related to how the nervous system communicates with the muscle.

You might notice it first in small ways — you’ll forget a name, lose your train of thought mid-sentence, or take twice as long to process simple instructions. You may tell yourself you’re just tired, but in MS, this feeling often has a name: brain fog.

Brain fog isn’t vague or metaphorical — it’s a neurological symptom. In fact, cognitive changes are so common in MS that 40–70% of people with MS experience measurable cognitive impairment at some point. In relapsing-remitting MS specifically, pooled data show about 32.5% of people meet criteria for impairment across two or more cognitive domains.

Yet, brain fog is often invisible, minimized, or disguised by fatigue, mood, or “just a bad day.” That makes understanding it — and managing it — crucial.

What Is Brain Fog in MS?

In neurological terms, “brain fog” refers to declines or slowdowns across these domains:

Living with MS often means juggling symptoms, fatigue, bladder issues, temperature sensitivity — and sometimes, hydration is the unsung factor influencing it all. Many people with MS avoid drinking enough water to reduce bathroom trips, but dehydration can worsen fatigue, cognition, and overall symptom control. A better approach is to hydrate smartly rather than limit fluids altogether.

✅ Hydration Correlates with Fatigue

• A study of 50 women with MS found that those with low hydration status (urine specific gravity, USG ≥ 1.015) reported higher fatigue scores compared to well-hydrated participants. PubMed

• The authors noted that limiting water intake (often due to bladder dysfunction) may worsen fatigue in MS. PubMed

Most people with MS know that hot weather or exercise can temporarily worsen symptoms. But many are surprised to find that the same thing can happen at night — in bed, under blankets, or even after a mild fever. This is Uhthoff’s phenomenon, and it affects up to 80% of people with MS.

What Is Uhthoff’s Phenomenon?

Uhthoff’s phenomenon is a temporary worsening of MS symptoms when body temperature rises. Even a small increase of 0.5°C (less than 1°F) can slow nerve conduction in demyelinated pathways. At night, body heat can rise from:

• Warm blankets, mattresses, or room temperature

• Hormonal changes (night sweats, menopause, etc.)

Constipation. Bloating. Sudden bowel urgency...These aren't just random issues — they’re common in MS, and they’re rooted in real neurological and immune system changes.

Recent studies show that up to 68% of people with MS experience chronic constipation, while nearly 50% report bloating, gas, or discomfort. These problems aren't caused by poor diet alone. Instead, they often stem from how MS affects the enteric nervous system, the gut–brain axis, and the immune system’s interaction with the microbiome.

MS doesn't stop at the brain and spinal cord. It disrupts communication between multiple systems — and the gut is one of the first to feel it.

The Gut–Brain–Nerve Connection in MS

The gastrointestinal (GI) tract is controlled by the enteric nervous system (ENS) — often called “the second brain.” It contains over 500 million neurons and communicates directly with the CNS through the vagus nerve and spinal pathways.

For many people living with multiple sclerosis (MS), one of the most frustrating and disorienting symptoms is suddenly losing track of what they were saying — forgetting a word mid-sentence, pausing unexpectedly, or feeling their mind “go blank” during a conversation.

This isn’t classic forgetfulness. It’s a neurologically based symptom caused by how MS disrupts brain function.

MS targets the central nervous system (CNS) — particularly the brain and spinal cord — and damages myelin, the protective sheath surrounding nerve fibers. When myelin is lost, electrical signals between brain regions slow down, misfire, or fail to transmit.

If this damage affects areas involved in language production (e.g., Broca’s area), working memory, or processing speed, the brain may struggle to organize and express thoughts in real time. Even when someone knows what they want to say, the signal may “drop” mid-sentence, mid-thought, or mid-word.

These cognitive-linguistic disruptions are commonly linked to:

Leg heaviness is a common yet underrecognized symptom in multiple sclerosis (MS).It’s not always about muscle weakness — many people with MS describe their legs as feeling heavy, hard to lift, or slow to respond, even when strength appears normal.

This sensation is often caused by neurological inefficiency — when damaged nerves make it harder for the brain to communicate with the muscles. The result: walking feels harder, stairs take more effort, and fatigue sets in faster.

Understanding the science behind leg heaviness can help patients and clinicians manage it more effectively — and validate what so many people feel but can’t always explain.

What Is Leg Heaviness?

People with MS often describe their legs as feeling:

Fatigue is one of the most common and disabling symptoms of multiple sclerosis (MS), affecting more than 80% of people with MS at some point during their disease. While physical fatigue is widely recognized, many people experience a less visible but equally debilitating form: cognitive fatigue.

What Is Cognitive Fatigue?

Cognitive fatigue refers to a decline in mental efficiency after sustained cognitive activity. It’s not just about feeling tired — it involves a measurable reduction in attention, processing speed, working memory, and executive function over time.

In MS, this occurs due to demyelination and neuroinflammation in the brain. Damaged myelin slows down or disrupts nerve conduction, forcing the brain to recruit more areas and expend more energy to complete basic cognitive tasks. Functional MRI studies have confirmed that people with MS show increased cortical activation during mental tasks, reflecting this compensatory overwork — which leads to faster mental fatigue.

What It Feels Like