What is fasting?
Fasting is when you don’t eat or drink anything, or limit what you eat or drink, for a certain period of time. Depending on your religion, it may be for certain days of the year or for a whole month.
Religions that promote fasting have rules to ensure you fast safely during pregnancy and breastfeeding. Australian health authorities also have helpful guidelines on how to fast safely.
Which religions require fasting, and for how long?
Many religions require fasting at certain times. Here are some examples.
The Islamic religion requires every healthy adult to fast from sunrise to sunset during the 9th month of the year, known as Ramadan. As the month of Ramadan is set by the lunar calendar, the solar (Gregorian) date will change from year to year. The length of the fast varies between about 12 and 17 hours each day. This depends on whether Ramadan happens in the winter or summer, and where you live.
Judaism has several major and minor fast days throughout the year. The most strictly observed is an almost 25-hour fast called Yom Kippur. Eating and drinking is forbidden from sundown on the eve of Yom Kippur, until the next sundown.
Christians fast on Ash Wednesday and Good Friday and don’t consume meat on any Friday of the year. When you are fasting, you are allowed one full-size meal during the 24-hour period and 2 smaller snacks throughout the day.
During the 6-week period of Lent, many Christians abstain from a luxury or a certain food of their choice.
Is religious fasting still mandatory during pregnancy?
The requirement to fast during pregnancy may vary depending on your religious sect and your individual medical situation. Here are some general rules:
- A Muslim who is pregnant or breastfeeding during the month of Ramadan is exempt from fasting. However, if you feel healthy, you may choose to fast.
- Christians who are pregnant or breastfeeding are also exempt from fasting on Ash Wednesday and Good Friday. But you are allowed to fast if you are healthy and choose to do so.
- The different Jewish fasting days pose different levels of stringencies. For the 4 less strict fast days, people who are pregnant or breastfeeding are exempt from fasting. On the 2 more stringent fast days (Yom Kippur and Tisha Ba’av), people who are pregnant or breastfeeding, and are healthy, can consider fasting.
You should talk to your doctor or midwife before you fast. There are many religiously-observant doctors in Australia who can discuss with you the risks associated with fasting — while being sensitive to your religious or spiritual needs.
How do I fast safely while pregnant or breastfeeding?
If you are pregnant and intend to fast, it’s best to plan ahead.
During Ramadan, in the hours where it is permissible to eat – or throughout the day before the Jewish Yom Kippur fast – drink plenty of water to stay hydrated throughout the fast. This is especially important if Ramadan falls during the summer, when the fast is longer and the weather is hotter.
Christians can still drink during their fasting days, so water, juice, tea and coffee are allowed.
Throughout pregnancy and breastfeeding it is important to eat nutritious food as part of a well-balanced diet, especially before and after a fast.
When should I consider not fasting?
Fasting on Yom Kippur may be required by Jewish law even while pregnant or breastfeeding, depending on your individual situation. If your labour begins on Yom Kippur, you should not continue your fast. If you give birth up to 3 days before Yom Kippur, you should also not fast.
During Lent, you are exempt from fasting if you are pregnant or breastfeeding. This means that unless you choose to fast, you don’t have to.
If you are experiencing any medical issues during your pregnancy, such as gestational diabetes or any other pregnancy complication, you should speak to your doctor and local religious leader before fasting. In general, it’s a good idea to confirm with your doctor or midwife that it is safe for you to fast.
Can fasting harm my baby?
Research on the effects of fasting on pregnancy is limited. However, some studies have shown that fasting during pregnancy does not affect the baby’s birth weight or increase the chance of a preterm birth.
If you are experiencing any medical issues or complications in your pregnancy, speak to your doctor or midwife before fasting.
Does fasting affect breastfeeding?
If you are breastfeeding and planning to fast, drink extra fluids in the days leading up to, and during, the fast. Try to minimise physical activities and exposure to heat as much as possible while fasting.
Fasting while breastfeeding is not likely to cause any harm to your baby.
It’s important to breastfeed as you usually would to keep your baby hydrated. You can check your baby’s hydration by monitoring their poos and wees and comparing it to a usual day. If you are concerned about your baby’s hydration, speak to a healthcare professional urgently.
You may find that for the next day or so after the fast, your baby may seem hungrier and want to feed more often. This is normal and you will usually settle back into your regular feeding routine in a few days.
If you or your baby have any medical problems, or your baby was premature, check with your doctor, midwife, or lactation consultant whether it’s a good idea for you to fast.
Where can I get more information about fasting?
Everyone is different, and the decision to fast while pregnant or breastfeeding is an individual one.
If you are concerned about your ability to fast while pregnant or breastfeeding, seek advice from a trusted healthcare professional (such as your doctor, midwife or lactation professional). It’s also a good idea to check with them if there any situations (such as feeling unwell) when you should break your fast.
You can also seek advice from your religious authority. Consider speaking to a doctor who shares your religious heritage.
For advice on Jewish observance, pregnancy, breastfeeding and fasting, visit Nishmat. This is an internationally recognised institute for women’s health and Jewish law. You can also ask your local Rabbi or religious leader.
Catholics can contact the Catholic Church in Australia if they have any questions about Lent.
Resources and support
- The Australian Breastfeeding Association has a guide to religious fasting and breastfeeding.
- The RMIT Health Promotion Unit offers tips on healthy fasting during Ramadan.
- Diabetes Australia provides advice on managing diabetes during Ramadan.
- Nishmat Women’s Health and Halacha website offers information on fasting during both major and minor Jewish fast days.
- The Catholic Voice discusses fasting and abstinence at Lent and the difference between them.
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Last reviewed: June 2023