Ramadan – the 18-hour fast that keeps the faithful coming back for more

For Muslims, the annual ritual is more than a spiritual 5:2 diet – it's a unifying way to take stock of how they are living

'It was really busy last year. It might be a bit less so this year. I think it's the World Cup." Fatima showed me the women's prayer room of the Harrow Central Mosque, a massive building, nine years in the making. Its domed room at the top has a scaffold tower in the middle, the last trace of building work. "There is no religious significance to the scaffolding," said Nadeem, the operations manager. "We're just waiting for one light. If you know anybody who wants to donate a six metre light ..."

The mood, at 8.46pm on Thursday, is giddy. Bushra, here with her five-month-old daughter Zahrah, says: "It's really buzzing. It's hard to describe, nobody's eating, but there's so much energy." Iftar, the breaking of the fast, is at 9.23. Prayers start five minutes before that. People start filing in from 9pm. Anything that is counted down in one-minute increments (racing; train travel) makes you feel excited.

That's just the human condition. But when it finally comes to it, and the dua (supplications) has been said, and the food is in front of everyone, and the milk the colour of Pepto-Bismol has been poured, the only people who seem hungry are the kids who weren't fasting anyway. Everybody else has fasted themselves full.

"As soon as you break your fast, you usually do it with one date and water," Bushra said. "But after that, you don't feel hungry. You spend all day thinking, I'm going to eat this, I'm going to eat that ... There's a saying in Punjabi, you can't fill your eyes."

"We have that!" I yell, way too loud. One of the things about being raised an atheist is that I can never work out how loud you should talk in religious buildings; as a general rule, if you're wondering, be less loud.

"The human body is capable of a lot. Many people go without food for many, many days. This is just a few hours," said Nadeem, modestly not mentioning that 3am til 9pm is actually 18 hours. It is a unifying time, which makes the mood generous. "No matter what your beliefs might be Islamically, everybody fasts," Bushra said. Fatima said later: "The religious element is very clear. You fast. These are the times. Obviously there's a wisdom in that."

And there's more to fasting than not eating. "It's about trying to be a better person, praying more frequently," Nadeem said. "Praying more frequently. When I'm fasting, I realise all the errors I'm making. It's a total stock take. It's a fast for the eyes and the ears as well, so you don't look at things you shouldn't be looking at, or hear things you shouldn't be hearing."

Shaykh Rahim converted/reverted to Islam 20 years ago and now runs the mosque's education programme. ("20 years ago, it would have been unheard of, for a revert to run the education programme," Bushra said later. I thought she meant it critically, but it turned out she was married to Rahim). "It's really a training of the spirit," he said.

"If you can avoid these basic things, it then enables you to address your bad attitude, your anger or your desire, or whatever comes over you. You develop your willpower and it's those things that really transform you, morally and ethically."

We headed downstairs, via a room full of wires, where Nadeem wanted to show me the nerve centre of their air conditioning system. The windows close automatically when they sense rain, and can be remotely operated by an iPhone on a different continent. I always mock a neophile, but it's only because I'm jealous of all their fancy stuff.

The two ground floor prayer rooms were filling up, although with food in the way, it wasn't the sea of people there would be later, when the service starts at 11pm.

The prayers said in the moments before the breaking of the fast, the dua, have a special resonance. "In the few minutes before the fast is broken, that's when God accepts your fast," Fatima said. So what are they praying for? "You ask for forgiveness. You ask for God's mercy. You ask for good health. You ask to be a better person. Over the years, it's been on auto. It's like a shopping list, where you buy the same thing every week," Bushra said, pragmatically.

She added later that people misunderstand who Muslims are. "They think we're an alien species, we don't have a sense of humour, we don't have careers, we don't want normal things."

"It is amazing, really, how much time Ramadan gives you," Fatima said. "You don't have to have breakfast, you don't have to have lunch. You don't have to think about dinner. The evenings seem so long. You should try it. It's not that different from the 5:2 diet."

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