Preparing your body for Ramadan: caffeine, sleep and a lighter first week
By DinFit · Published 29 October 2026 · How these articles are made
Every claim on this page names its source. It has been checked against those sources, not reviewed by a health professional.
A registered dietitian writing for the British Dietetic Association suggests cutting down on caffeine in the week before Ramadan, switching to decaffeinated tea and coffee, herbal tea or water, which can mean fewer headaches and better sleep.1 A 2023 sports medicine guideline for healthy people suggests keeping the first week of Ramadan's training light to moderate, then building up gradually.2 Here is what lies behind both suggestions, and what else changes when the fast begins.
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Why ease off caffeine before Ramadan?
A 2004 review of 57 experimental studies found that stopping caffeine can bring on headache, tiredness, low energy, drowsiness, low mood, trouble concentrating and irritability.3 In those studies, symptoms usually began 12 to 24 hours after the last dose, peaked between 20 and 51 hours, and lasted 2 to 9 days, and stopping as little as 100 milligrams a day was enough to bring them on.3 In Ramadan, a morning coffee moves to the evening, or stops. The 2023 guideline also suggests avoiding coffee and tea between iftar and suhoor, because they make you pass more water.2
What changes in sleep?
Across 24 studies, total sleep fell from about 7.2 hours a night before Ramadan to 6.4 hours during it.4 A 2017 review found that in everyday settings bedtime and waking time move suddenly later in Ramadan, while studies that kept sleep schedules fixed found no rise in daytime sleepiness.5 The 2023 guideline suggests adapting to Ramadan's sleep schedule gradually, going to bed earlier if you are a morning person or later if you are an evening person.2 Sleep in Ramadan goes further into why sleep shifts and what helps.
Who this research is about
The people in those 24 studies had a median age of 23.7 years, and 73 percent of them were men.4
Why a lighter first week?
The guideline's panel notes that the same effort feels harder while fasting, with heart rate and perceived effort higher than when not fasting, and suggests light to moderate sessions in the first week, then raising the intensity gradually through weeks two to four.2 The dietitian's page notes that dehydration and hunger can feel worse in the first week of Ramadan, as the body adjusts.1 The guideline also warns against cutting training back too far, since that loses fitness.2
Who this research is about
The guideline's recommendations are expert opinion, the lowest of its three levels of evidence, and are written for healthy people, most of them for athletes.2
Can you practise before Ramadan begins?
The guideline encourages coaches to rehearse fasted training with their athletes before Ramadan, to ease worries about training while fasting and to help them cope.2 It also notes that people who have fasted through many Ramadans seem to cope better than those fasting for the first time.2
Who this research is about
Both points are expert opinion, written for athletes and their coaches.2
If you live with a health condition, take regular medication, are pregnant or breastfeeding, or have had an eating disorder, talk to your doctor about training and eating while you fast.
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- Frascina C. Ramadan and diet. British Dietetic Association, 1 April 2022. On bda.uk.com
- Chamari K, Guezguez F, Khalladi K, et al. Aspetar clinical guidelines: Ramadan fasting and exercise for healthy individuals. Tunis Med. 2023;101(1):1-14. PMID 37682254. Full text on PMC
- Juliano LM, Griffiths RR. A critical review of caffeine withdrawal: empirical validation of symptoms and signs, incidence, severity, and associated features. Psychopharmacology (Berl). 2004;176(1):1-29. PMID 15448977. Record on PubMed
- Faris MAE, Jahrami HA, Alhayki FA, et al. Effect of diurnal fasting on sleep during Ramadan: a systematic review and meta-analysis. Sleep Breath. 2020;24(2):771-782. PMID 31832984. Record on PubMed
- Qasrawi SO, Pandi-Perumal SR, BaHammam AS. The effect of intermittent fasting during Ramadan on sleep, sleepiness, cognitive function, and circadian rhythm. Sleep Breath. 2017;21(3):577-586. PMID 28190167. Record on PubMed
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