Some months ago, I decided to go on a crash diet. As I’m a doctor and I was about to film Channel 4’s How To Lose Weight Well, it seems I’m also a hypocrite who loves irony. Doing a show on healthy weight loss while making drastic changes to my diet for quick results forced me to confront just how much health professionals hate “diets”.


The diets I’m talking about are temporary changes to eating habits. But health professionals don’t want temporary change. We doctors always tell people (to quote the NHS website): “Avoid fad diets… the only way to lose weight healthily and keep it off is to make permanent changes to the way you eat and exercise.”

Great advice in theory, but is it realistic? I would love to see my patients eat better and exercise more – I’d love to do it myself! – but we’re only human and it’s hard to stay trim all the time. Sometimes we just want to look our best for a special occasion: a wedding, a beach holiday, a school reunion or, worst of all, presenting a TV show about dieting. There’s a huge diet industry that says this is reasonable, and a huge medical industry that says it isn’t. So which is right?

Ideally you’ll make lifelong healthy changes, but if you don’t, finding good advice backed by medical evidence on how to lose weight quickly is difficult. The truth is that not all fad-diets are created equal, but the sheer range of options is too huge and too complicated for most people to choose one confidently. I surveyed hundreds for the programme and it was exhausting, and sometimes unexpected.

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So here I’m offering some easy-to-follow tips that worked for me as a doctor... and as a human being who occasionally wants to look a bit better than I really am!

1. Keep a diary

Use an app or a diary to record everything you eat and drink – and be completely honest. You should be able to identify a few things that are holding you back. For me, it was the snacks I ate when I got home from work.

2. Some foods make you hungry

Sugary foods such as chocolate bars and soft drinks can make you hungrier than if you’d eaten nothing at all. If you need a snack, aim for something that will deal with your body’s craving for sugar, but suppress your appetite for longer. Stick to about 150 calories: I like an apple and a few almonds.

3. Trick your stomach

Foods that have few calories per 100g, such as vegetables and fruit, are a great way of filling up. My rule of thumb is to make vegetables count for two-thirds of every plate at lunch and dinner. Among my favourites are stir-fried kale, cabbage or broccoli, with a stock cube or some soy sauce thrown in.

4. Trick your brain

Having a full stomach doesn’t always make you stop eating: we’ve all had the experience of continuing to consume calories long after we feel fit to burst. But protein is great at suppressing appetite-increasing hormones so that you don’t want to eat more. Aim to fill about a third of your plate with protein (meat or fish – or tofu if you’re vegetarian).

5. Alcohol is the enemy

Alcohol has a lot of calories – and, more importantly, it impairs your decision-making. It’s much harder to say no to a pudding after a few drinks – and a fry-up is almost irresistible when you have a hangover. For rapid weight loss, I’d recommend cutting out booze entirely.

6. Exercise with care

A work-out can stimulate your appetite and also make you feel that you’ve earned the right to some extra dinner. That said, I try to exercise regularly – the health benefits are undeniable.

7. Go easy with the blender

Blending fruit and vegetables releases their sugars much more quickly, destroys much of the fibre that keeps you full, and means you can eat them so quickly that you’re ready for more food very soon.

8. Beware addictive foods

Some processed foods are designed to make you eat a lot of them. Studies show that ice cream affects the brain’s reward system in almost the same way as cocaine. For fast weight loss, cut out all processed foods: they’re almost impossible to stop eating.

9. Never take diet pills

High-street diet pills don’t work at all and some of those offered on the internet are extremely dangerous. Stay well away from all of them.

10. Short-term diets that (mostly) work…

There is good medical evidence supporting the effectiveness of the 5:2 diet (so-called because you “fast”, on around 500 calories for women, 600 for men, for two days each week). It’s a good diet – and not just for weight loss – but not many people can stick to it for long.

The strangest diet I came across was the KEN diet (Ketogenic Enteral Nutrition). The idea came from a doctor’s observation that patients fed through nasal tubes have virtually no appetite. It involves the insertion of a small tube down your nose and into your stomach: you then wear a pump in a backpack that drip-feeds you, 24 hours a day, for ten days. Weight loss is rapid (5kg to 10kg) as you consume almost no calories, and patients describe few or no symptoms of hunger. It sounds extreme – and certainly having a tube taped to your nose for ten days isn’t for everyone – but it worked well as a quick fix.


How to Lose Weight Well begins on Channel 4 today (Monday 11th January) at 8.00pm