Maintaining Blood Sugar During Fasting
know how to maintain blood sugar during fasting, understand the basics, how to prepare for pre-fasting, and choose the right foods to maintain healthy levels.
Written by Dr. J T Hema Pratima
Reviewed by Dr. Rohinipriyanka Pondugula MBBS
Last updated on 4th Aug, 2025
Introduction
Fasting is a common practice for religious, health, or personal reasons. However, for people with diabetes or those prone to blood sugar fluctuations, fasting can be challenging. If not managed carefully, it may lead to dangerously high or low blood sugar levels.
This article will guide you on how to maintain stable blood sugar levels while fasting, ensuring you stay healthy and energised.
Understanding Blood Sugar and Fasting
When we eat, our body breaks down food into glucose (sugar), which provides energy. Insulin, a hormone produced by the pancreas, helps cells absorb this glucose. During fasting, since no food is consumed, the body relies on stored glucose (glycogen) and fat for energy.
For people with diabetes or insulin resistance, this process may not work smoothly, leading to:
Hypoglycemia (Low Blood Sugar): Weakness, dizziness, sweating, confusion. Hyperglycemia (High Blood Sugar): Excessive thirst, frequent urination, fatigue.
Consult a Top Diabetic doctor
Tips to Maintain Healthy Blood Sugar While Fasting
1. Pre-Fasting Preparation
Follow the instructions below for pre-fasting preparation:
Consult Your Doctor: If you have diabetes, check if fasting is safe for you. Your doctor may adjust medications or insulin doses.
Monitor Blood Sugar Regularly: Keep a glucometer handy to track levels before, during, and after fasting.
Stay Hydrated: Drink plenty of water during non-fasting hours to prevent dehydration, which can affect blood sugar.
2. Choose the Right Foods
Follow the steps below for choosing the right food
During Non-Fasting Hours (Suhoor/Pre-Fast Meal):
Complex Carbohydrates: Oats, whole wheat bread, brown rice, and quinoa release energy slowly.
High-Fibre Foods: Vegetables, lentils, and beans help stabilise blood sugar.
Healthy Fats & Proteins: Eggs, nuts, yoghurt, and lean meats keep you full longer.
Avoid Sugary & Processed Foods: White bread, sweets, and fried foods cause rapid sugar spikes and crashes.
Breaking the Fast (Iftar/Post-Fast Meal):
Start with Water & Dates: Dates provide quick energy but consume in moderation (1-2 dates).
Include Protein & Fibre: Grilled chicken, fish, salads, and whole grains help balance blood sugar.
Limit Sweets & Fried Foods: Opt for fruits like apples or berries instead of sugary desserts.
3. Stay Active (But Avoid Overexertion)
Light exercises like walking or stretching can help regulate blood sugar.
Avoid intense workouts during fasting hours to prevent low blood sugar.
4. Recognise Warning Signs
Low Blood Sugar (Below 70 mg/dL): Dizziness, sweating, shakiness—break the fast immediately with juice or glucose tablets.
High Blood Sugar (Above 200 mg/dL): Extreme thirst, fatigue—consult a doctor if levels remain high.
5. Break the Fast if Necessary
Your health comes first. If you feel unwell, it’s okay to stop fasting and seek medical advice.
When to Seek Medical Help
If you experience:
Severe dizziness or fainting
Persistent high/low blood sugar
Extreme fatigue or confusion
Final Thoughts
Fasting can be safe with proper planning, especially for those managing diabetes. Focus on balanced meals, hydration, and regular blood sugar checks. Always prioritise your health and consult a doctor if needed.
Consult a Top Diabetic doctor
Consult a Top Diabetic doctor
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