From the first sip of water at suhoor to the quiet relief of iftar, Ramadan reshapes your daily rhythm in a deeply personal way. For millions of people around the world, fasting during this holy month is both a spiritual and physical experience. But what exactly happens inside your body when you go without food and drink from dawn to sunset?

Understanding the science behind Ramadan fasting can help you approach the month with awareness, balance, and confidence—while staying mindful of your health.

How Ramadan Fasting Works in the Body

Ramadan fasting involves abstaining from food and drink between dawn (suhoor) and sunset (iftar). Depending on where you live, this can mean fasting for 12 to 18 hours or more.

During these hours, your body shifts from being in a “fed state” to a “fasted state.” This natural metabolic transition affects your energy use, digestion, hormones, and hydration levels. For most healthy adults, the body adapts remarkably well.

The First Few Hours: Using Stored Energy

Glycogen Breakdown Begins

After your last meal at suhoor, your body starts by using glucose from your bloodstream for energy. Within several hours, it begins breaking down glycogen—stored glucose in the liver and muscles.

This process helps maintain stable blood sugar levels. You may feel normal at this stage, especially if your pre-dawn meal included complex carbohydrates like oats, whole grains, or lentils.

Hunger Signals Appear

As blood sugar levels gradually drop, hunger hormones such as ghrelin increase. You might notice stomach growling or mild irritability.

These feelings are normal. In fact, the body often adapts after the first few days, and many people report reduced hunger as Ramadan progresses.

Mid-Fast: Shifting to Fat for Fuel

After about 8–12 hours without food, your body increasingly turns to fat stores for energy. This metabolic shift is similar to what happens in other forms of intermittent fasting.

Fat breakdown produces ketones, which can serve as an alternative fuel source. While this sounds technical, many people simply notice steadier energy and fewer sharp hunger spikes after the initial adjustment period.

For example, someone who felt sluggish on the first day might feel more alert by the fifth or sixth day.

Hydration Changes and Their Effects

Mild Dehydration

Unlike some fasting practices, Ramadan fasting also restricts fluids during daylight hours. This can lead to mild dehydration, especially in hot climates or during longer days.

Common signs include dry mouth, mild headaches, and fatigue. Drinking water consistently between iftar and suhoor helps your body rehydrate effectively.

Electrolyte Balance

Electrolytes like sodium and potassium play an important role in muscle function and fluid balance. If iftar meals are very salty or sugary, you may feel bloated or thirsty the next day.

A balanced approach—water, fruits, vegetables, and moderate salt—supports smoother hydration.

What Happens to Digestion During Ramadan?

Slower Daytime Digestive Activity

Without food entering the stomach during the day, digestive activity slows down. The stomach continues producing acid, but at lower levels compared to when you eat regularly.

Some people worry that fasting might cause an ulcer, but evidence suggests that in healthy individuals, fasting alone does not directly cause a stomach ulcer. However, people who already have conditions like gastritis or a history of ulcer disease may notice discomfort.

Iftar and Digestive Overload

When you break your fast, the digestive system suddenly becomes active again. Eating a very large, heavy meal—especially fried or spicy foods—can lead to bloating, acid reflux, or stomach pain.

Imagine fasting all day and then quickly eating several fried snacks and sugary drinks. It’s not surprising that your stomach may protest.

Simple tip: Start with water and light foods such as dates and soup before moving to a balanced meal.

Ramadan and Stomach Health: What About Ulcer Risk?

The relationship between fasting and ulcer development is often misunderstood.

A stomach ulcer is usually caused by infection with Helicobacter pylori bacteria or long-term use of certain medications like nonsteroidal anti-inflammatory drugs (NSAIDs), according to the Mayo Clinic.

For most healthy individuals, Ramadan fasting does not create an ulcer. However, people who already have peptic ulcer disease may experience symptoms such as burning stomach pain, nausea, or heartburn during prolonged fasting.

If someone has a known ulcer or ongoing stomach issues, it’s important to discuss fasting plans with a healthcare professional before Ramadan begins.

Blood Sugar and Insulin Changes

Improved Insulin Sensitivity (In Some Cases)

Fasting naturally lowers insulin levels during the day. For some people, especially those who are overweight, this can improve insulin sensitivity over time.

However, this effect varies from person to person and depends heavily on overall diet and lifestyle. If iftar and suhoor meals are high in refined sugar and deep-fried foods, potential metabolic benefits may be reduced.

Considerations for Diabetes

People with diabetes need special guidance before fasting. The World Health Organization emphasizes that individuals with chronic medical conditions should consult healthcare providers before making significant dietary changes.

Ramadan fasting can be safe for some individuals with well-managed diabetes, but it requires careful planning and medical supervision.

Weight Changes: Why Results Differ

Some people lose weight during Ramadan. Others gain weight. Why the difference?

Weight changes depend on total calorie intake, food quality, sleep, and activity levels. Fasting during the day does not automatically guarantee weight loss.

For example, someone who eats balanced portions at iftar and stays moderately active may lose a small amount of weight. In contrast, someone who frequently consumes large, high-calorie meals and desserts may gain weight.

The body responds to overall patterns, not just fasting hours.

Energy Levels and Mental Clarity

Initial Fatigue

During the first few days, you may feel tired, especially if your sleep schedule changes. Waking early for suhoor and staying up late for prayers can reduce total sleep time.

This temporary fatigue is often more related to sleep disruption than fasting itself.

Adaptation and Focus

As your body adapts, many people report improved focus and mental clarity. Stable blood sugar levels and reduced constant snacking may contribute to this effect.

However, experiences vary. If you feel persistent dizziness, weakness, or confusion, it’s important to pay attention to your body’s signals.

Hormones and Circadian Rhythm

Ramadan shifts meal timing to nighttime hours, which affects your circadian rhythm—the internal clock that regulates sleep and hormones.

Late-night meals and altered sleep patterns can influence hormones such as cortisol and melatonin. Over time, your body adjusts, but prioritizing consistent sleep between iftar and suhoor helps maintain balance.

A practical example: going to bed at the same time each night, even if it’s later than usual, can reduce next-day grogginess.

Gut Health and Microbiome Changes

Emerging research suggests that intermittent fasting patterns, including Ramadan-style fasting, may influence the gut microbiome—the community of bacteria in your digestive tract.

Balanced meals rich in fiber, fruits, vegetables, and fermented foods can support healthy gut bacteria. On the other hand, frequent high-fat, low-fiber meals may negatively affect digestive comfort.

While research is ongoing, dietary quality remains key.

Heart Health and Blood Pressure

Some studies indicate that Ramadan fasting may have neutral or modestly positive effects on blood pressure and cholesterol in healthy adults.

According to the Cleveland Clinic, heart health is closely linked to diet quality, weight management, and physical activity. Fasting alone is not a cure or risk factor; lifestyle patterns matter most.

Staying hydrated and choosing balanced meals can support cardiovascular health during Ramadan.

When Fasting May Not Be Safe

While fasting is safe for many healthy adults, certain groups should seek medical advice before participating:

• People with uncontrolled diabetes
• Individuals with advanced kidney disease
• Those with active ulcer complications
• Pregnant or breastfeeding women
• People with certain chronic illnesses

The National Health Service advises that individuals with ongoing health conditions consult their doctor if they are unsure about fasting.

Listening to your body and seeking guidance is a responsible and faith-consistent approach.

Practical Tips for a Healthier Ramadan

These general wellness tips may help support your body during fasting:

At Suhoor

• Include protein (eggs, yogurt, beans) for sustained fullness.
• Choose complex carbohydrates for slower energy release.
• Drink enough water.

At Iftar

• Break your fast gently with water and light foods.
• Avoid rushing into very large meals.
• Include vegetables and fiber to support digestion.

Between Meals

• Stay hydrated.
• Prioritize sleep when possible.
• Engage in light physical activity, such as walking.

These habits can reduce digestive discomfort and help prevent issues like acid reflux, even in those concerned about ulcer risk.

A Gentle Perspective on Balance

Ramadan is not just about physical fasting; it’s also about mindfulness, moderation, and spiritual reflection. From a health standpoint, your body is designed to adapt to short-term changes in eating patterns.

For most healthy individuals, Ramadan fasting leads to temporary metabolic shifts—using stored energy, adjusting hormones, and altering digestion. These changes are usually reversible and well tolerated.

However, existing medical conditions such as an ulcer or chronic disease require thoughtful planning and professional guidance.

Conclusion: What Ramadan Really Does to Your Body

Ramadan fasting prompts your body to switch energy sources, regulate hormones differently, and adjust to new hydration and sleep patterns. In healthy adults, these changes are generally safe and manageable.

The experience varies from person to person. Factors like diet quality, hydration, sleep, and underlying health conditions all play a role.

Rather than focusing on fear—such as worrying that fasting will automatically cause an ulcer—it’s more helpful to approach Ramadan with awareness and balance. Nourish your body wisely, respect its limits, and seek medical advice if you have existing health concerns.

With mindful habits, Ramadan can be both a spiritually meaningful and physically sustainable experience.

FAQs

1. Does Ramadan fasting cause an ulcer?

For healthy individuals, fasting alone does not typically cause a stomach ulcer. Most ulcers are linked to bacterial infection or certain medications. However, people with existing ulcer disease may experience symptoms and should consult a healthcare professional.

2. Is it normal to feel tired during Ramadan?

Yes, especially during the first few days. Changes in sleep patterns and meal timing often contribute to fatigue. Energy levels usually stabilize as the body adapts.

3. Can Ramadan help with weight loss?

It can, but it depends on total calorie intake and food choices. Balanced meals and portion control are key factors.

4. How can I reduce digestive discomfort at iftar?

Start with water and light foods, avoid overeating, and limit very spicy or fried items. Eating slowly can also help.

5. Who should not fast during Ramadan?

People with uncontrolled chronic conditions, advanced kidney disease, active ulcer complications, or certain other medical issues should seek medical advice before fasting.

References

World Health Organization – Healthy Diet
Mayo Clinic – Peptic Ulcer
Cleveland Clinic – Intermittent Fasting Overview
National Health Service (NHS) – Fasting and Health Conditions
Centers for Disease Control and Prevention (CDC) – Healthy Weight and Nutrition

Disclaimers

Image Disclaimer:
Some images used in this article are AI-generated for illustrative purposes.

Medical Disclaimer:
This article is for informational purposes only and does not replace professional medical advice. Always consult a qualified healthcare provider for medical concerns.