The Alkaline diet vs the 5:2 diet

Two hot new regimes have caught on since New Year, each promising pain-free weight loss. Can either make the pounds melt away? Kate Hilpern gives the low-down

The Alkaline diet

What is it?

Although she hardly looks like someone in need of losing weight, Victoria Beckham is the latest star to try the most recent version of this diet, the Honestly Healthy Alkaline Programme, which involves eating mainly alkaline foods in order to keep the body's pH between 7.35 and 7.45. Other celebrity fans include Gwnyth Paltrow (her again) and Kirsten Dunst. The Alkaline diet doesn't just claim to help you lose weight – many websites advocating it claim it can heal a wide range of ailments including arthritis, diabetes and cancer, as well as slowing the ageing process. Authors of Honestly Healthy, nutritional therapist Vicki Edgson and organic chef Natasha Corrett, say that the diet can improve energy levels and memory and help prevent headaches, bloating, heart disease, muscle pain and insomnia.

Where does it come from?

Back in the 19th century, the French biologist Claude Bernard discovered that changing the diet of rabbits from herbivore (mainly plant) to carnivore (mainly meat) turned their urine from more alkaline to more acid. Excited by his discovery, subsequent scientists built on his findings, which eventually led to a bunch of loosely related diets (other names include the alkaline ash diet and the acid alkaline diet), whose popularity has recently taken off after the celebrity take-up.

What's the theory?

Our blood is slightly alkaline, with a normal pH level of between 7.35 and 7.45. The theory behind the alkaline diet is that our diet should reflect this pH level (as it did in hunter-gatherer days when we ate fewer acid-producing foods such as grains, fish, meat, poultry, dairy and salt).

Proponents of alkaline diets believe a diet high in acid-producing foods disrupts this balance and promotes the loss of essential minerals such as potassium, magnesium, calcium and sodium as the body tries to restore equilibrium. This imbalance is thought to make people prone to illness and gaining weight. The ultimate aim is to eat 70 per cent alkaline foods and 30 per cent acid foods, meaning you can still have a little of the "bad" stuff such pasta and rice, although things can get slightly complicated. The way you cook your vegetables, for example, can have an impact. Raw spinach is alkaline, but when you cook it, it becomes acidic.

What do the experts say?

"The theory of the alkaline diet is that eating certain foods can help maintain the body's ideal pH balance to improve overall health. But the body maintains its pH balance regardless of diet," says British Dietetic Association spokesperson, Rick Miller.

What's more, while there is evidence that alkaline diets may help prevent the formation of calcium kidney stones, osteoporosis, and age-related muscle wasting, there isn't any proof that an acid-producing diet is the foundation of chronic illness.

Mind you, says Miller, you're unlikely to do yourself any harm. "The diet's premise is to increase alkalizing foods (such as fruit and vegetables) and reduce your intake of acid foods (such as meat, salt, and refined grains). Well, that's pretty much what we consider as healthy eating anyway and if you're overweight, of course it will probably help you shift some pounds."

How punishing is it?

Fans of this diet say the fact that it's un-faddy makes it easier. "It doesn't cut out food groups or involve counting calories, which is probably why it's the first diet I've ever got on with," says Alison Heldon, 24.

But most people agree that the fact that the regime warns against any "very acid-forming" foods, such as starchy grains and vegetables – such as pasta, wheat and beans – all dairy products, meat, fish and shellfish, means it's challenging. You can also forget about indulging in coffee, tea, sugar, fizzy drinks including soda and tonic water and alcohol. "I defy anyone with a normal family life to sustain it in the long term – I think I did well to last six weeks," says Suzanne O'Shea, 33. Monitoring your pH levels isn't very glamorous either – you have to test your urine.

The 5:2 diet

What is it?

Intermittent fasting, basically. So you eat normally for five days and severely restrict your calories for the other two – 600 calories for men and 500 for women. It's up to the dieter how they divide them up – so you might, for example, have scrambled eggs with ham and a black coffee for breakfast (300 calories) and a lunch or dinner of grilled fish or meat with vegetables (300 calories). The rest of the time, you eat what you want.

Where does it come from?

The diet virtually became an overnight sensation after featuring in a BBC2 Horizon documentary last summer by health journalist Dr Michael Mosley. After just five weeks, Mosley lost nearly a stone, reduced his body fat by about 25 per cent and improved his blood-sugar and cholesterol levels. A book, The 5:2 Diet Book, has become a bestseller. Advocates of the diet also claim it can help us live longer and decrease the risk of cancer, diabetes and Alzheimer's. Gwyneth Paltrow, Jennifer Aniston and Jennifer Lopez are said to have tried it.

What's the theory?

The rationale behind it centres on the effects of fasting on levels of a hormone called IGF-1 (Insulin-Like Growth Factor 1). Although the hormone is essential in early life, when rapid new cell growth is advantageous, high levels in adulthood increase your risk of cell divisions such as those found in cancer. Restricting the calories you consume, so the theory goes, lowers blood levels of IGF-1, protecting you against some major diseases. Mosley fell upon the particular success of cutting back for two days a week virtually by default. Having tried various patterns of intermittent fasting, he eventually discovered that severely restricting food for two days a week was both achievable and had the best results. The sheer simplicity of the diet has no doubt had a hand in its phenomenal success.

What do the experts say?

Despite the claims that it helps people lose weight, increases their lifespans, improves cognitive function and protects against conditions such as dementia and Alzheimer's, the general medical consensus is that there isn't actually any firm evidence.

"Yes, there's some work on the effects of intermittent fasting on ageing and cognitive decline, but almost all these studies involve rodents, not humans, and the work on preventing diseases took place in laboratory conditions, with no guarantee of successful real-world outcomes," says British Dietetic Association spokesperson, Rick Miller.

He warns that if you're only eating a quarter of the calories you need, you may suffer low blood-sugar, as well as digestive problems, and that unless dieters increase their water consumption on their restricted days, they could suffer from constipation.

"I used to eat like the 5:2 diet in my teens and early 20s and it was called bulimia," says Zoë Harcombe, author of The Obesity Epidemic book, who is concerned that this diet carries a huge risk of encouraging disordered eating in people who are prone to it.

Sarah Schenker, spokesperson for the Nutrition Society, agrees: "The reality is that the 5:2 diet is how a lot of people manage their weight naturally. You eat all you want on the weekend, then have a day or two when you cut right down – and it does work for people. Also, there's something to be said for giving our systems a rest, particularly if we eat a lot of sugar and carbohydrates. So I don't think it's a fad and I'm certainly not dismissive, although I think we need to do more research."

Some experts believe that on the eating days, there's a risk of over-indulging and putting on weight, although a study by the University of Illinois found that people only eat about 100-110 per cent of the calories they needed. It's quite hard to fully make up for the lack of food on the restricted days.

How punishing is it?

People report that the diet is both easy and hard. On the fasting days, it's hard not to give into snacks, but the rest of the time, you can eat what you want so there's no guilt. "On the restricted days, I have very little energy, which can affect my work, and I'm usually quite irritable by the evening, but then I just remind myself that I can eat what I want tomorrow and that cheers me up," says Susan Kemp, 34.

Others report that it's not sustainable. "I lost 8lb in just over two weeks and I did manage to keep it off for a few months, but if you think about it, the restricted days are just slightly shy of 30 per cent of your week. Who wants to be starving for 30 per cent of their life?" says Alan Mitchell, 40.

ebooks
ebookA delicious collection of 50 meaty main courses
Life and Style
ebookNow available in paperback
  • Get to the point
Latest stories from i100
Have you tried new the Independent Digital Edition apps?

ES Rentals

    Independent Dating
    and  

    By clicking 'Search' you
    are agreeing to our
    Terms of Use.

    iJobs Job Widget
    iJobs General

    Ashdown Group: Junior Project Manager (website, web application) - Agile

    £215 per day: Ashdown Group: Junior Project Manager (website, web application ...

    Guru Careers: Business Development Manager / Sales

    £30 - 40k (£65k Y1 OTE Uncapped): Guru Careers: We are seeking a Business Deve...

    Guru Careers: Graduate Media Assistant

    Competitive (DOE): Guru Careers: We are looking for an ambitious and adaptable...

    Guru Careers: Solutions Consultant

    £30 - 40k (DOE) + Benefits: Guru Careers: We are seeking a Solutions Consultan...

    Day In a Page

    Fishing for votes with Nigel Farage: The Ukip leader shows how he can work an audience as he casts his line to the disaffected of Grimsby

    Fishing is on Nigel Farage's mind

    Ukip leader casts a line to the disaffected
    Who is bombing whom in the Middle East? It's amazing they don't all hit each other

    Who is bombing whom in the Middle East?

    Robert Fisk untangles the countries and factions
    China's influence on fashion: At the top of the game both creatively and commercially

    China's influence on fashion

    At the top of the game both creatively and commercially
    Lord O’Donnell: Former cabinet secretary on the election and life away from the levers of power

    The man known as GOD has a reputation for getting the job done

    Lord O'Donnell's three principles of rule
    Rainbow shades: It's all bright on the night

    Rainbow shades

    It's all bright on the night
    'It was first time I had ever tasted chocolate. I kept a piece, and when Amsterdam was liberated, I gave it to the first Allied soldier I saw'

    Bread from heaven

    Dutch survivors thank RAF for World War II drop that saved millions
    Britain will be 'run for the wealthy and powerful' if Tories retain power - Labour

    How 'the Axe' helped Labour

    UK will be 'run for the wealthy and powerful' if Tories retain power
    Rare and exclusive video shows the horrific price paid by activists for challenging the rule of jihadist extremists in Syria

    The price to be paid for challenging the rule of extremists

    A revolution now 'consuming its own children'
    Welcome to the world of Megagames

    Welcome to the world of Megagames

    300 players take part in Watch the Skies! board game in London
    'Nymphomaniac' actress reveals what it was really like to star in one of the most explicit films ever

    Charlotte Gainsbourg on 'Nymphomaniac'

    Starring in one of the most explicit films ever
    Robert Fisk in Abu Dhabi: The Emirates' out-of-sight migrant workers helping to build the dream projects of its rulers

    Robert Fisk in Abu Dhabi

    The Emirates' out-of-sight migrant workers helping to build the dream projects of its rulers
    Vince Cable interview: Charging fees for employment tribunals was 'a very bad move'

    Vince Cable exclusive interview

    Charging fees for employment tribunals was 'a very bad move'
    Iwan Rheon interview: Game of Thrones star returns to his Welsh roots to record debut album

    Iwan Rheon is returning to his Welsh roots

    Rheon is best known for his role as the Bastard of Bolton. It's gruelling playing a sadistic torturer, he tells Craig McLean, but it hasn't stopped him recording an album of Welsh psychedelia
    Morne Hardenberg interview: Cameraman for BBC's upcoming show Shark on filming the ocean's most dangerous predator

    It's time for my close-up

    Meet the man who films great whites for a living
    Increasing numbers of homeless people in America keep their mobile phones on the streets

    Homeless people keep mobile phones

    A homeless person with a smartphone is a common sight in the US. And that's creating a network where the 'hobo' community can share information - and fight stigma - like never before