Why people try intermittent fasting: what a survey of 514 fasters found

Why do people try intermittent fasting? Researchers at King Saud University asked 514 adults in Saudi Arabia who practise it, in an online survey run in March and April 2021. Most respondents were women (88%). Weight loss was the most common reason, at 45%. A third of respondents had more than one reason, 11% fasted mainly for their health and 7% for religious reasons.

16:8 was the most popular schedule (44%), followed by a 12-hour fast (26%), and most people (58%) had been fasting for less than three months. 61% said their health had improved. Three in four said they felt less hungry, and 62.5% said they ate less than before. Weight loss was modest: 35% had lost less than 2.2 kg and 21% hadn't lost any. 37% reported no side effects. Tiredness and hunger were the most common, followed by headaches and dizziness.

Most people learned about fasting on social media (62%); only 6% heard about it from a health professional. 85% didn't use a fasting app. Asked about the future, 37% planned to fast until they reached their goal and 21% planned to keep going for life. The authors call their results preliminary, because the answers were self-reported and the respondents were recruited through social networks, and they call for more research.

General information, not medical advice. Don’t fast without talking to a doctor if you’re pregnant or breastfeeding, under 18, have had an eating disorder, have diabetes, or take insulin or other medicine that lowers blood sugar.