Fasting in Diabetes? A Physician’s Advice.

Fasting in Diabetes? A Physician’s Advice.

If you are a diabetic or have a relative who is suffering from diabetes then this article is for you. You will find all the information you need on fasting and diabetes. What will happen if you fast? Is it safe for diabetics to fast? What do you need to take care of? Here is a guide to answer all your questions. 

Intentional refraining from eating is known as Fasting. Physiologically speaking fasting is the metabolic state of the person who hasn’t consumed anything overnight or after complete digestion and absorption of a meal. Fasting, a partial or complete abstention from all foods or a particular set of foods is a part of many cultural and religious practices in India. People also fast for various other reasons like losing weight or for living a healthy lifestyle.

Benefits of fasting

  • Fasting reduces the risk of metabolic diseases
  • It helps reduce inflammation and promotes overall health
  • It helps in losing weight
  • It helps boost a person’s cognitive performance  i.e the ability of the brain to think and execute function.
  • It protects from obesity and other diseases associated with it like coronary heart disease, hypertension, atherosclerosis, etc
management of diabetes in fasting

Diabetes mellitus (DM) is a metabolic disease that occurs due to the absence of the hormone insulin. This hormone is responsible for providing glucose (sugar) to the cells of our body. Without it, all the sugar from the food we eat remains in the blood and is not able to get reach within the body cells where it is needed. Excess sugar in the blood settles in other organs like eyes, kidney, and other body parts forming conjugates. These conjugates are toxic to our metabolism and they, in turn, lead to damage to the organ. At the same time, the working and functioning of the cells are hampered, as they are deprived of glucose which is present in abundance in the blood but can’t reach inside the cells.

How anti-diabetic medications work?

In a nutshell, medications are aimed at either lowering the blood glucose level or increasing the insulin concentration or a combination of both. Synthetic insulin, as a part of management of type 1 diabetic patients, aims at reducing the blood sugar level by pushing it into the cells where it belongs. This basic knowledge of the treatment plan is really important in managing your own disease.

Fasting has been uniformly discouraged by medical professionals and healthcare providers for patients with diabetes. Here is a complete guide to help you, if you still wish to fast. 

what happens to your body when you fast?

What happens if a diabetic fasts?

  • Low blood sugar (hypoglycemia)
  • Very high blood sugar (hyperglycemia)
  • Rise in the level of acids in the blood 
  • Dehydration and blockage of arteries.

Let’s take a look at each one in detail and how we can avoid them.

1. Low blood sugar levels (hypoglycemia) in Diabetic patients during fasting

Hypoglycemia accounts for 2 to 4% of mortality in patients with type 1 DM. It occurs in patients when they refrain from consuming food completely or partially but are still taking medications. The medications continue to lower the patient’s blood sugar but no new calories or glucose gets added from the diet. The end result is hypoglycemia. Medically speaking a blood sugar level of less than 70mg/dL results in symptoms of hypoglycemia.

How to know you are having hypoglycemia or low sugar levels in your blood?

  • Sweating
  • Cold clammy skin and palms
  • Feeling nervous or anxious
  • Increased heart beat/palpitations
  • Confusion
  •  Irritability or impatience
  • Feeling dizzy or lightheaded
  • Hunger
  • Nausea/ feel like vomiting
  • Blurred vision
  • Tingling numbness in the lips, tongue and cheeks.
  • Coordination problems, clumsiness
  • Seizures
  • syncope/Passing out 
  • Impaired coherence
  • Nightmares or crying out during sleep.

 Not all patients show all these signs. A diabetic can easily recognise low blood sugar levels from a set of signs that are particular to his body. If you are experiencing any of these, then  you should immediately break your fast and consume food. 

2.Very high blood sugar levels (hyperglycemia)

There are two reasons why a diabetic who is fasting, can end up with high blood sugar levels. A very common cause is when patients themselves alter medication doses say- taking half a tablet. They do so assuming the food intake is low so the medication dose also should be low. 

Another very common reason is indulging in foods that are restricted for a diabetic. When a person breaks fast, hsi body is highly responsive to any food item that he takes in. At this moment people usually indulge in consuming high quantities of starch rich, low fibre, oily foods that cause a surge in the patient’s sugar levels.

Long term hyperglycemia or an ill-controlled sugar level is a leading cause of morbidity and mortality in diabetics. It is associated with complications like damage to kidneys ( diabetic nephropathy), damage to eyes (diabetic retinopathy). It can also cause damage to nerves (diabetic neuropathy), blockage in blood vessels that leads to stroke or coronary artery diseases like  heart attack. 

What happens when a diabetic fasts/

How to avoid hyperglycemia when a diabetic is fasting?

The number one way to avoid both hyper and hypoglycemia in a  fasting diabetic is to monitor his blood sugar levels. Continuous blood sugar monitoring in the form of fasting blood sugar levels and postprandial is a must.

Fasting blood sugar levels can be monitored first thing in the morning without consumption of any food item (on an empty stomach).

Post prandial blood sugar levels can be measured at 2 hours after consumption of meals.

3.Increased acid concentration in the blood (diabetic ketoacidosis DKA)

Patients with diabetes especially with type 1 who have been fasting for long periods like in Ramadan or Navratra are more prone to developing DKA. 

DKA means an increase in the levels of ketone bodies and other acids in the blood. It occurs more commonly in diabetics whos blood sugar levels were p[poorly controlled just before the fasting period. 

Another common reason for DKA in diabetics is the reduction of insulin doses assuming the consumption of food is going to be less during the month.

Diabetics are more prone to infertility especially females who have diabetes along with PCOS.

How to know that you are having Diabetic Ketoacidosis (DKA)?

Symptoms of DKA develop quickly sometimes within 24 hours. And for some people it is the first sign of diabetes and warrants a visit to their health care provider.

Signs and symptoms of DKA

  • Excessive thirst
  • Frequent urination
  • Nausea and vomiting
  • Abdominal pain
  • Weakness or fatigue
  • Shortness of breath
  • Fruity-scented breath
  • Confusion

When to contact your doctor?

If you are a diabetic and fasting,

  1. You are vomiting and are unable to eat any liquid or solids
  2. Your blood sugar level is high and doesn’t respond to treatment that is prescribed like your daily insulin dose.
  3. Your urine ketone level is moderate or high. urine ketone levels can be easily checked using an over the counter urine dipstick test. It is highly advised that all duiabetic patients should keep this with them at all times. It can help avoid many untoward situations and hospital admissions.

Untreated diabetic ketoacidosis can be fatal. Acting immediately is the key to a good prognosis. Seek medical help immediately if you are getting any of the above symptoms. Also can be completely managed if you are in a hospital setting as it needs constant monitoring of your blood glucose and acid levels and adjustments in insulin doses.

components of diabetes management

4.Dehydration (depletion of water) 

Dehydration occurs when you don’t have enough water and other bodily fluids to carry out the normal functions of the body. There are many reasons due to which a patient of diabetes can get dehydrated. 

Here are the common ones.

  1. It can be a result of a hot and humid climate when excessive perspiration occurs and the body loses water by sweating. 
  2. It can also occur among diabetic individuals who perform hard physical labour while fasting
  3. A poorly controlled sugar level can lead to hyperglycemia that causes frequent and excessive urination known as osmotic diuresis. 

Signs and symptoms of dehydration

  1. Feeling thirsty
  2. Having headaches
  3. Dry mouth and dry eyes
  4. Feeling dizzy
  5. Feeling tired
  6. Dark yellow coloured urine

Symptoms of severe dehydration

  1. Low blood pressure
  2. Sunken eyes
  3. A weak pulse and/or rapid heartbeat
  4. Feeling confused
  5. Lethargy

What can you do at home to manage dehydration?

If you are getting symptoms of mild dehydration when drinking plenty of fluids is the best thing to do. Plain water is the best replacement. Refrain from drinking fruit juices or fizzy drinks because if you dehydration is accompanied by hyperglycemia, then these can only make the condition worse. 

Do not self-adjust your insulin dose.

If you are experiencing symptoms of severe dehydration then contact your healthcare provider immediately. you will need a replacement of not only fluids but also electrolytes depending upon the blood levels and management of your blood sugar levels. All this monitoring will not be possible at home and needs expert medical intervention.

Know more about how your diet influences your mood and emotional state from an expert.

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5. Blockage of arteries (thrombosis that occurs due to dehydration) 

It presents a multitude of symptoms depending upon the organ involved. It can present with blurry vision, a heart attack, reduced or no urine output or syncope due to a sudden fall in blood pressure (orthostatic hypotension).

The best way to avoid these complications is a good long term sugar control.

Fasting is a personal choice. 

However it should be dictated by sound judgement and expert advice from your healthcare provider. Keep him/her in the loop each time you fast. Look for the signs and symptoms that are indicative of red flag signs as mentioned above. Do not self adjust doses. Diabetes has a relentless progress. You can’t stop it but you can definitely slow its effect on your body organs by living a healthy lifestyle.

That’s it for today, Until then

Stay healthy stay happy.

I hope you found this post useful and if you have any queries, comments, suggestions, feel free to connect with me. 

Medical Disclaimer: The Content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health providers with any questions you may have regarding a medical condition and don’t delay seeking help because of something you read here on doctormommyspeaks site.

Dr. Rahat Sayyad
Dr. Rahat Sayyad

Physician, Author, Host of Doctormommyspeaks Parenting Podcast and a mom of two. I am here to offer my help in the form of well-researched articles, expert interviews with Gynecologist, Paediatricians, Nutritional Therapists, Psychologist, Parenting Coaches, etc on my Podcast and website.

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This Post Has 12 Comments

  1. sanandita

    You’ve answered a lot of questions that cloud our minds. With Navratris coming, am sure this will be of help!

  2. Cindy DSilva

    Wow this is indeed helpful for those fasting despite their diabetic issue. I have also told my friends many times that they should get their body healthy and then fast otherwise they are just ruining their bodies even more. No im not a doctor.

  3. Arti Singh

    Very nice and informative blog on Fasting and Diabetes… Thank you for sharing this

  4. Mridula

    That’s so so informative doctor. Will share with people around

  5. Disha

    I have family around who have diabetes and will share this post with them. Thanks for the detailed post.

  6. Shamik

    A very useful post Doctor. Thanks for sharing it. It has answered a lot of questions for me, especially when there is diabetic patient at home.

  7. Atulmaharaj

    Thanks Dr. for sharing an informative post, sharing it with Diabetic folks in my family.

  8. preety85

    Very informative post!! My in-laws are diabetic,I will share this points with them.

I'd love to know your thoughts