The Alternate Day diet: what is it and can it help you lose weight?

The Alternate Day Diet (also known as Intermittent Fasting, The Longevity Diet and the Up Day Down Day diet) encourages you to eat half your normal calorie intake every other day.
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  • The Alternate Day diet apparently triggers a gene that encourages the body to burn fat.

    In the 1930s it was discovered that a low-calorie diet increased life expectancy by around 30%. All very well, but not many of us would be prepared to be on an eternal diet.

    However, in 2003, scientist Dr Mark Mattson discovered that these health benefits could also be enjoyed if the calories were only cut every other day.

    The Alternate Day Diet was born! Find out how to do it with our diet plan.

    Dr James Johnson wrote a book, The Alternate Day Diet, based on the theory that halving your calorie intake every other day will help you lose weight.

    He suggests you stick to halving your calorie intake every day for two weeks to kick-start your diet, then start doing it every other day. This will maintain your initial weight loss. If you want to lose more, then you will need to reduce your calories on your ‘down days’ to around 35%.

    The daily intake is 2,000 calories for women and 2,500 for men.

    How does the Alternate Day diet work?

    Some scientists believe that the drop in calorie intake triggers a skinny gene to kick in. This gene, called SIRT1, blocks another gene from storing fat.

    Your body then starts using your fat reserves, therefore making you lose weight.

    Who is the Alternate Day Diet good for?

    The diet is good for anyone who hates depriving themselves of delicious food, as you can eat what you like on the ‘up days’ (without, of course, bingeing).

    The diet is also good for anyone who doesn’t want to follow difficult meal plans or who refuses to cut out any particular foods.

    The eating plan is one you can follow for life, as eating just half your normal intake on your ‘down days will’ maintain your weight loss.

    Dr James Johnson, who devised the Alternate Day Diet, claims the plan can reduce the symptoms of asthma, prevent heart disease and breast cancer and make you live longer, too.

    Skeptics worry a very low calorie eating plan does not encourage a healthy, balanced diet.

    You need to make sure you eat lots of fruit and veg on your ‘feast days’. The temptation may be to eat loads of junk food when you’re allowed, but you have to be disciplined and make sure you are giving your body all the vitamins and minerals it needs.

    You do need to be able to spend time adding up the calories on your ‘fast days’.

    What do you do on the Alternate Day Diet?

    For the first two weeks of the eating plan you need to halve your calorie intake every day. After this fasting stint, go back to eating what you normally do every other day, and stick to fasting on the days in between.

    Make sure you have lots of water every day and exercise regularly on your ‘feast’ days.

    For your ‘down days’ (or fasting days), you should only be eating half your calorie intake. For a woman this is 1,000 calories, for a man, 1,250.

    To help you keep count, choose a selection from the meals and snacks below. Remember to drink lots of water and to add the calories of all drinks you have as well.

    Alternate Day diet low-calorie breakfasts

    Pomegranate, raspberry and banana smoothie 169 calories

    Porridge with nuts and fruit 253 calories

    Skinnier cooked breakfast 472 calories

    Alternate Day diet low-calorie salads

    Roasted courgette and tomato couscous 426 calories

    Alternate Day Diet low-calorie soups

    Lentil and bacon soup 340 calories

    Rosemary Conley’s pepper soup 141 calories

    Carrot and leek soup 120 calories

    Carrot and mint soup 140 calories

    Slimy pond pea soup 377 calories

    Tuscan bean soup211 calories

    Alternate Day Diet low-calorie dinners

    Courgette pasta bake 293 calories
    Tuna with nectarine salad 264 calories

    Low-fat fish and chips 428 calories

    Sweet chilli salmon 345 calories

    Alternate Day Diet low-calorie puddings

    Low-fat lemon and berry roulade 297 calories

    Sticky pear and chocolate pudding 313 calories

    Alternate Day Diet low-calorie snacks

    One rice cake – 35 calories
    Small bag of Twiglets – 97 calories
    3 celery sticks stuffed with cottage cheese – 75 calories
    8 cashew nuts – 100 calories
    Cadbury’s Flake – 99 calories
    Fun-size Milky Way – 76 calories

    Alternate Day Diet low-calorie drinks

    125ml glass of red or dry white wine – 85 calories
    Flute of Champagne – 90 calories
    Diet lemon Bacardi Breezer – 98 calories