Can You Fast With Diabetes? Navratri, Karva Chauth and Chhath Explained

A great many Indians face this choice. The ICMR-INDIAB-17 national survey, published in 2023, estimated diabetes in 11.4 per cent of Indian adults and prediabetes in another 15.3 per cent. Many of them fast for faith and family, and most of the research on doing it safely comes from a different religious fast altogether.

Can people with diabetes fast safely?

Many can, provided the diabetes is stable and the plan is made with the doctor in advance. Risk runs on a scale. Someone controlled on diet and metformin alone has a low chance of a dangerous low during a phalahar fast. Someone on insulin or a sulfonylurea, or with a history of severe hypoglycaemia, faces a real one, and a waterless fast adds dehydration on top. Practical guidelines from the International Diabetes Federation and the DAR International Alliance, written for Ramadan, sort people into very high, high, and moderate or low risk before any fast begins. That approach transfers well to Hindu vrats, as long as you allow for their different food and water rules.

Why a fast can push blood sugar both down and up

Two opposite problems sit inside one fast. When food stops, the liver releases stored glycogen and then makes fresh glucose, while insulin levels drift down. In a person without diabetes this keeps blood sugar level. If a tablet or injection keeps insulin high while no food arrives, sugar can fall too far, which is hypoglycaemia. The reverse happens as well. A long gap followed by fried kuttu puris, aloo sabzi and sweetened milk sends glucose sharply upwards, and people who skip medicine without advice can run high all day. Dehydration concentrates the blood and makes both problems worse, which is why the waterless fasts carry the most risk.

How is a Navratri fast different from Karva Chauth and Chhath?

They differ in length, water and food, and those three things set the risk. A Navratri vrat usually runs 9 days, water is allowed, and most people eat phalahar: fruit, milk, curd, sabudana, potatoes and vrat flours, often as one or two meals a day. Karva Chauth is a single day, traditionally nirjala, running from the pre-dawn sargi to moonrise, typically 14 to 16 hours without food or water. Chhath is the hardest. After the kharna meal, many women keep a nirjala fast of about 36 hours through the evening and dawn offerings to the sun, standing waist-deep in river or pond water. Dizziness while standing in cold water is a genuine hazard for anyone prone to lows.

Which diabetes medicines make fasting risky?

Insulin and sulfonylureas carry the highest risk, because both lower blood sugar whether or not you have eaten. In India the common sulfonylureas are glimepiride, gliclazide and glibenclamide, often combined with metformin in a single tablet, so read the strip. Metformin, the DPP-4 inhibitors such as sitagliptin, vildagliptin and teneligliptin, and pioglitazone rarely cause lows on their own. SGLT2 inhibitors such as dapagliflozin and empagliflozin raise a different worry: they make the kidneys pass sugar and water, so a day without fluids dehydrates faster, and guidance treats them with extra caution in dry fasts. None of this is a reason to stop or move a tablet yourself. Timing and dose changes belong to the doctor who prescribed them.

What the Ramadan research tells a Hindu who fasts

Almost all the evidence comes from Ramadan, because that is where fasting with diabetes has been studied at scale. The EPIDIAR survey of 12,243 people with diabetes across 13 countries found severe hypoglycaemia several times more frequent during the fasting month than in other months, and more common among those who changed their dose or activity. The later CREED study of 3,250 people with type 2 diabetes found that 94.2 per cent fasted for at least 15 days. In a 2012 randomised trial in India and Malaysia, symptomatic lows were recorded by 4.1 per cent of Indian patients switched to sitagliptin, against 7.7 per cent who stayed on a sulfonylurea. Ramadan allows food and water after sunset, so a nirjala Hindu fast is, if anything, the harsher test.

Who should not fast at all?

Some people should not keep a full fast, and a gentler version is widely accepted in Hindu practice. The IDF-DAR guidance places these groups at high or very high risk: type 1 diabetes, anyone who has had severe hypoglycaemia or diabetic ketoacidosis in the previous three months, people who no longer feel their lows coming, pregnancy with diabetes, advanced kidney disease, and older people who live alone or have memory problems. Poorly controlled type 2 diabetes with very high recent readings belongs on the list, as does anyone with fever, vomiting or diarrhoea on the day. For these people a phalahar fast with water, milk and fruit at fixed times keeps the devotion without the gamble.

What blood sugar reading means you must break the fast?

Break it at once if the glucometer shows below 70 mg/dL, or above 300 mg/dL, at any hour. Those are the thresholds in the IDF-DAR guidance, and they apply however close moonrise or the evening arghya may be. Break it too for symptoms of a low even without a meter: shaking, sweating, a pounding heart, sudden hunger, confusion or blurred vision, and for fainting or repeated vomiting. Treat a low with 15 to 20 g of quick sugar, such as three or four glucose tablets or half a glass of juice, and recheck after 15 minutes. A finger-prick test is neither food nor drink, so test before the fast, at midday, in the late afternoon and before eating.

Is a nirjala fast riskier than a phalahar fast for diabetes?

Yes, noticeably. When water is allowed, the main danger of a phalahar fast is high sugar from starchy vrat foods, which is unpleasant but slower to turn dangerous. Without water, the blood becomes more concentrated, blood pressure can drop on standing, and anyone taking an SGLT2 inhibitor or a diuretic for blood pressure loses fluid faster still. Warm October afternoons in the north and the standing, bending and walking of Chhath rituals add to the strain. If the choice is open, a Karva Chauth kept with water and a glass of buttermilk at midday is far safer than a strict nirjala one, and plenty of families now accept that version.

What should a person with diabetes eat before the fast starts?

A pre-dawn meal that digests slowly: protein, fibre and some fat, with a modest portion of starch. Paneer or curd, a chilla of kuttu or rajgira flour, a small handful of nuts, a guava or an apple, and two or three glasses of water spread across the hour serve far better than pheni in sweetened milk, mithai and parathas. The aim is to begin the fast with sugar in a sensible range rather than spiking from a sweet sargi and crashing by noon. Karva Chauth has its own guide to what to eat in sargi and how to break the fast, and the flours themselves are weighed up in kuttu, singhara and rajgira atta compared.

Which vrat foods raise blood sugar fastest?

Sabudana, potatoes, singhara flour, sweetened milk and fruit juice raise it fastest, and they fill most vrat thalis. Sabudana is almost pure starch, as the piece on whether sabudana suits weight loss explains, and a plate of sabudana khichdi with aloo is a large carbohydrate load with little to slow it. Fried kuttu puris add fat that delays the rise but stretches it late into the night. Sweet phalahar such as makhana kheer, and the halwa served at kanya puja, lands on top. Gentler choices are curd, paneer, roasted makhana, nuts, cucumber, bottle gourd and whole fruit in small portions. The diabetic-friendly recipe collection has ideas that adapt to vrat rules.

Building a phalahar plate that holds sugar steady for nine days

Use the same plate model you would on any ordinary day. Half the plate goes to vegetables your family's vrat permits, such as lauki, pumpkin, cucumber or tomato. A quarter goes to protein: paneer, curd, a glass of milk, or a small handful of peanuts or makhana. The last quarter is starch, one small kuttu or rajgira roti or half a katori of samak rice, rather than sabudana and potatoes together. Spread food over two or three meals instead of one large evening feast, keep water, unsweetened nimbu pani and buttermilk coming, and decline the fried snacks that arrive with every visitor. The Navratri fasting diet plan covers the wider nine-day structure.

How should you break a fast with diabetes?

Gently and on time: water first, a measured amount of carbohydrate, then a proper meal within half an hour. At Karva Chauth or Chhath, sip a glass of water, check the sugar if you can, and take the ritual sweet as one small piece rather than a plateful. Then eat an ordinary balanced meal of dal, roti or rice, vegetables and curd, not a spread of puris, pakoras and kheer after a day of nothing. A heavy fried meal after a long fast produces the highest readings of the whole festival, often late at night. Take evening medicines exactly as the doctor set them for the fast day, and test again two hours after eating.

Does fasting help reverse type 2 diabetes?

Not on its own, and certainly not a festival fast. Research on structured calorie restriction shows that some people with early type 2 diabetes reach remission when they lose a substantial amount of weight, but that is a supervised programme lasting months, not nine days of phalahar or one nirjala day. The feasting that follows a festival fast can easily undo any short-term dip in readings. Regular fasting patterns are a separate question with their own evidence and their own cautions, set out in the guide to intermittent fasting on an Indian diet.

The talk to have with your doctor before the festival

Book it two to four weeks ahead, not the evening before. Take your medicine strips, your latest HbA1c and a week of glucometer readings, and say plainly which fast you mean to keep, for how many days, and whether you will drink water. Ask what changes on fast days, what to do if the reading falls below 70 mg/dL, and when to abandon the fast. Anyone on insulin should ask for written instructions covering both the fast day and the feast day after it. A dietitian or diabetes educator can then turn that medical plan into meals, portions and a testing routine that fit your family's customs.

Why this judgement takes proper training

Advising a fasting client with diabetes is where general healthy-eating tips stop being enough. The practitioner has to read a prescription without altering it, recognise the drug classes that make a fast dangerous, apply the IDF-DAR risk groups to Navratri, Karva Chauth and Chhath, and still respect a practice the client will not give up. That is the ground NNWA's Diabetes Educator course covers, in live classes taught by faculty such as Dr Sucharita Sengupta, who holds a PG Certificate in Diabetes Education. Its fee is published, with EMI available. For everyday meal planning, NNWA's diet clinic offers consultations, while medicine decisions stay with your doctor.

The short version

Many people with diabetes can keep a festival fast, but not everyone and not every kind. Insulin and sulfonylureas make lows likely, SGLT2 inhibitors make a waterless fast riskier, and pregnancy, type 1 diabetes, kidney disease and recent severe lows all argue for a gentler version. Plan with the doctor weeks ahead, eat a slow pre-dawn meal, test through the day, and stop the fast below 70 or above 300 mg/dL. Build vrat meals on protein and vegetables rather than sabudana and potatoes, and end the fast with a normal meal instead of a fried feast.

Research this article draws on

Anjana et al. (2023). Metabolic non-communicable disease health report of India: the ICMR-INDIAB national cross-sectional study (ICMR-INDIAB-17)00119-5). The Lancet Diabetes & Endocrinology. A national survey across Indian states estimated diabetes in 11.4 per cent and prediabetes in 15.3 per cent of adults, which is why festival fasting with diabetes is a common clinical question.

Salti et al. (2004). A Population-Based Study of Diabetes and Its Characteristics During the Fasting Month of Ramadan in 13 Countries. Diabetes Care. Among 12,243 people with diabetes, most with type 2 fasted at least 15 days, and severe hypoglycaemia was several times more frequent during Ramadan, especially when people changed doses or activity.

Babineaux et al. (2015). Multi-country retrospective observational study of the management and outcomes of patients with Type 2 diabetes during Ramadan in 2010 (CREED). Diabetic Medicine. Of 3,250 people with type 2 diabetes, 94.2 per cent fasted at least 15 days; physicians increasingly gave fasting advice and adjusted treatment beforehand. Observational and industry-funded.

Aravind et al. (2012). Hypoglycemia in patients with type 2 diabetes from India and Malaysia treated with sitagliptin or a sulfonylurea during Ramadan: a randomized, pragmatic study. Current Medical Research and Opinion. In 848 fasting patients, symptomatic lows were about half as common after switching from a sulfonylurea to sitagliptin; in India the figures were 4.1 against 7.7 per cent. Events were self-reported without confirmatory readings.

Hassanein et al. (2017). Diabetes and Ramadan: Practical guidelines. Diabetes Research and Clinical Practice. IDF and DAR guidance on risk stratification, nutrition and medicine adjustment for fasting with diabetes, including the glucose thresholds at which a fast should be broken.