On the Channel 4 show, slimmers have been following an intermittent fasting diet plan and taking part in regular exercise. Dr Michael Mosley has previously spoken on the best diet tips for starting out.
He said: “If you’re planning to try intermittent fasting, I would normally recommend that you do it more gradually.
“So start by consuming your food in 12 hours, and fasting the rest of the time, then you move on to a 10 hour period of eating.
“One thing I would say is there is mounting evidence that it is better if you finish your evening meal earlier, rather than having a late meal, skipping breakfast, and then going to lunchtime.
“So however you do time restricted eating, I would recommend you try and stop eating by 8pm and then not eat anything again with calories before breakfast the next day. If you are fasting for 12 hours, you can have breakfast at 8am.”
Having dinner earlier in the day can make it easier to fast and stop people from overeating, Dr Mosley explained.
He continued: “Broadly, I encourage people to try and have their evening meal earlier, say 7pm to 7.30pm.
“Try and stop eating by 8pm, and then not eat anything with calories after that.
“The temptation is to eat cheese and biscuits late into the night. Although the idea that cheese will give you nightmares is a complete and utter myth, it will obviously be sort of quite a lot of calories loaded on late at night.
“And we know the fat and sugar you eat late at night, it just hangs around in your system for much, much longer because your body is just closed down for the night.
“Your digestive process will be closing down, and it really will not appreciate that late night snack.”
High protein foods like meat, fish, eggs, beans and pulses can help slimmers feel fuller for longer.
These foods can also help boost the metabolism, which speeds up fat-burning in the body.
Dr Mosley added: “It’s really important to have a decent amount of protein, which is 50 to 70 grams a day.
“You can mainly get protein from meat or from fish, and you can also get it from legumes, but you have to eat rather more, which is why following the Fast 800 on a vegetarian diet is more challenging.
“We do have meal replacement shakes which are very rich in protein, and we’re also aiming to produce protein boosters, to help people who might otherwise struggle with it. The reason for protein is you need it for your muscle.
“You need it for all sorts of essential metabolic processes. And also because when you consume it, it’s digested slower by your body so you don’t get the same sort of peaks.”