Why do I feel shaky and jittery? Understanding the causes

September 26, 2025 •

5 min read

According to health statistics, millions of people experience episodes of unexplained shakiness and jitteriness. Understanding why do I feel shaky and jittery is the first step toward identifying triggers, managing symptoms, and addressing any potential underlying health concerns with authority and confidence.

Quick Summary

The shaky, jittery feeling can stem from a range of issues, from simple lifestyle factors like caffeine and dehydration to stress, anxiety, or low blood sugar. Occasionally, it signals a more serious medical condition like a thyroid disorder or essential tremor, warranting a closer look at the body's signals.

Key Points

Caffeine and Adrenaline: Too much caffeine stimulates adrenaline, a key cause of jitters and shaky feelings.
Anxiety's Physical Response: Stress triggers the 'fight-or-flight' response, flooding your system with hormones that cause muscle tension and shaking.
Hypoglycemia Warning: Low blood sugar can cause sudden shakiness, a symptom of the brain being deprived of its main energy source.
Lifestyle Factors: Dehydration, lack of sleep, and fatigue can all disrupt nerve function and cause physical shakiness.
Know the Red Flags: Persistent or worsening shakiness, especially with other symptoms, warrants a doctor's evaluation to rule out underlying conditions like thyroid issues or essential tremor.
Actionable Relief: Immediate fixes include deep breathing, grounding techniques, and a healthy snack, while long-term management involves reducing stimulants and managing stress.

Common Culprits Behind Shakiness and Jitters

Many instances of feeling shaky are linked to daily habits and physiological responses that are not serious. Understanding these common causes can help you make simple adjustments to find relief.

Caffeine Overload

Caffeine is a potent stimulant that affects your central nervous system by blocking adenosine receptors, which are responsible for making you feel tired. This can trigger the release of stress hormones like adrenaline, leading to an overstimulated feeling that manifests as jitteriness and shaky hands. Your personal tolerance for caffeine is influenced by genetics, body weight, and metabolism, meaning a small amount for one person could be too much for another.

Stress and Anxiety

When you experience stress or anxiety, your body enters a "fight-or-flight" response. This triggers a surge of adrenaline and cortisol, prepping your muscles for action. This can cause increased heart rate, shallow breathing, and muscle tension, which can feel like uncontrollable shaking or an internal jittery sensation. This response can occur even when there is no immediate physical threat.

Low Blood Sugar (Hypoglycemia)

Your body and brain rely on a steady supply of glucose for energy. When blood sugar levels drop too low, your body reacts with classic hypoglycemia symptoms, including shakiness, sweating, dizziness, and weakness. This is common if you have gone too long without eating, especially for individuals with diabetes, but it can affect anyone. Eating a carb-rich snack can help stabilize blood sugar and alleviate symptoms.

Dehydration and Lack of Sleep

Being dehydrated affects your body's electrolyte balance, which is crucial for muscle and nerve function. This imbalance can manifest as muscle weakness and shakiness. Similarly, a lack of adequate sleep can exhaust your nervous system, impacting your body's reflexes and leaving you feeling unsteady and fatigued.

Medication Side Effects

Certain medications can cause tremors or a feeling of internal restlessness as a side effect. This includes some drugs for asthma, antidepressants, and high blood pressure. If you've started a new medication and noticed an increase in shakiness, it is important to discuss it with your doctor.

When Shakiness Points to a Deeper Issue

While many causes are benign, persistent or severe shakiness can sometimes indicate an underlying medical condition that requires professional attention.

Essential Tremor

Essential tremor is a neurological disorder that causes rhythmic, involuntary shaking. Unlike the resting tremor seen in Parkinson's, essential tremor is most noticeable when you are trying to perform a task, such as reaching for something or writing. It can start mildly and worsen over time, often running in families.

Thyroid Disorders

An overactive thyroid gland, or hyperthyroidism, produces an excess of thyroid hormones that can speed up your body's metabolism. This can lead to a range of symptoms, including fine tremors in the hands, a rapid heart rate, weight loss, and nervousness. A blood test can easily diagnose this condition.

Neurological Conditions

Conditions that affect the nervous system, such as Parkinson's disease or multiple sclerosis (MS), can cause tremors and motor control issues. These are often accompanied by other specific symptoms that help doctors differentiate them from more common causes of shakiness. A Parkinson's tremor, for example, is typically a resting tremor.

Heart Problems

Certain heart rhythm issues or other cardiovascular problems can cause palpitations or an irregular heartbeat, which some people perceive as a jittery feeling in their chest or throughout their body.

Comparison of Common Causes


Feature	Anxiety	Hypoglycemia (Low Blood Sugar)	Caffeine Overload
Onset	Often sudden, triggered by stress or specific thoughts.	Can be sudden, especially if meals are skipped or delayed.	Usually develops soon after consuming a large amount of caffeine.
Associated Symptoms	Rapid heartbeat, shortness of breath, dizziness, sweating, feeling of dread.	Sweating, dizziness, confusion, hunger, irritability, rapid pulse.	Increased heart rate, nervousness, upset stomach, restlessness.
Immediate Action	Grounding techniques (5-4-3-2-1), deep breathing, distraction.	Eat a sugary snack or drink; follow with a balanced meal.	Drink water to flush out system; eat a fiber/protein-rich snack.
Relief Time	Varies, can resolve within minutes to a panic attack's duration.	Can improve within 15-30 minutes of eating carbohydrates.	May last several hours as the body metabolizes the caffeine.

Immediate and Long-Term Strategies for Relief

Dealing with the unsettling sensation of shakiness requires both in-the-moment calming techniques and sustainable lifestyle changes.

Immediate Relief

Practice Deep Breathing: Slow, controlled breaths can help lower your heart rate and calm your nervous system. Try the 4-7-8 method: inhale for 4 seconds, hold for 7, and exhale for 8.
Use Grounding Techniques: Focus on your senses to anchor yourself in the present moment. The 5-4-3-2-1 method (name 5 things you see, 4 you can touch, etc.) is effective for anxiety-induced jitters.
Drink Water and Eat a Snack: If you suspect low blood sugar or dehydration, have a glass of water and a snack containing carbohydrates and protein.
Engage in Light Exercise: A short walk or some gentle stretching can help burn off excess adrenaline and relieve muscle tension.

Long-Term Prevention

Reduce Stimulants: Gradually cut back on caffeine and nicotine, and monitor how your body responds.
Manage Stress: Incorporate relaxation practices like meditation, yoga, or spending time in nature to build resilience against stress.
Ensure Regular Sleep: Prioritize 7-9 hours of quality sleep per night to allow your body and nervous system to rest and reset.
Balanced Diet: Maintain stable blood sugar levels by eating regular, balanced meals and avoiding excessive amounts of sugar.
Consult a Professional: For persistent or severe symptoms, speaking with a doctor can help rule out underlying conditions and create a suitable treatment plan.

In some cases, tremors can be a side effect of medication. For information on specific drugs, you can consult a reliable source. Learn more about medication-induced tremors from MedlinePlus.

Conclusion

Feeling shaky and jittery is a common experience with a wide range of potential causes, from simple lifestyle factors to more complex medical issues. By paying attention to your body's signals and making informed choices about your diet, stress levels, and sleep, you can often find relief. However, if the symptoms are severe, persistent, or accompanied by other concerning signs, it is always best to seek professional medical advice to ensure your well-being.

Frequently Asked Questions

Yes, anxiety is a very common cause of an internal jittery or shaky feeling. The release of adrenaline and cortisol during the fight-or-flight response can create a physical sensation of trembling, even if you don't appear to be shaking externally.

Jitteriness is often a nervous or restless feeling that can be caused by stimulants, stress, or low blood sugar and is usually temporary. A tremor, on the other hand, is a rhythmic, involuntary muscle contraction that causes shaking and can be a symptom of a neurological condition.

Low blood sugar shakiness is often accompanied by sweating, dizziness, confusion, and hunger. Caffeine jitters typically occur shortly after consuming a caffeinated beverage and may also involve a racing heart and restlessness, without the associated hunger or extreme weakness of hypoglycemia.

You should see a doctor if your shakiness is persistent, severe, interferes with daily activities (like writing or eating), or is accompanied by other symptoms like headaches, weakness, or changes in walking. A doctor can help determine the underlying cause.

For low blood sugar, eating a balanced snack with carbohydrates and protein (like an apple with peanut butter) can stabilize glucose levels. For caffeine jitters, foods rich in fiber and protein can slow caffeine absorption. Avoiding excess sugar is also beneficial.

Essential tremor is not life-threatening, but it can become severe enough to interfere with a person's quality of life and daily tasks. It is often progressive and requires a diagnosis from a doctor to manage symptoms.

Immediate remedies include deep breathing exercises to calm the nervous system, drinking water to combat dehydration, eating a quick snack for low blood sugar, or using grounding techniques to distract from anxious thoughts.