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Welcome,

We are here to guide you toward a healthier, happier life.

Interval Weight Loss is the only scientifically proven program to prevent weight regain.

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Hey ,
With IWL you’re in
good hands.

I have worked on developing IWL based on a decade of researching weight management. Supported by a team of qualified and accredited dietitians, my program is the only scientifically backed approach that will see you lose weight and keep it off.

Dr Nick Fuller

Obesity expert from The University of Sydney & Founder of IWL

Obesity expert from The University of Sydney

What makes IWL
different?

We’ll give you videos and reading that focus on habits not dieting.
There’s no meticulously weighing out grams of food to eat.
There’s no spending all night in the supermarket looking for obscure ingredients to cook.
There’s no cutting out your favourite foods.
There’s no calorie counting.
There’s no following strict, militant exercise programs.
You will lose weight in 4-week cycles with 6 simple steps.
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The last weight loss program you'll ever need! Despite what the dieting industry spin you, no weight loss programs/diets address the biological imperative to regain weight. IWL does. IWL actually prevents the body's response to weight loss, so not only do you lose weight but you keep it off.

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Why IWL works

Lose weight, only for it to creep back on plus more? You can blame that on one thing: biology.

Dieting is one of the biggest stresses you can impose on your body. When you diet, your body thinks it is going to be starved for a long time and so holds on tight to where it is now.

Research has proven that we all have a ‘set point’ – a weight that we protect and bounce back to after every bout of dieting.

Unlike other weight loss programs, IWL addresses your ‘set point’ and prevents the body’s usual response by losing small amounts of weight across a month, followed by a month of maintaining that new weight.

Unlike diets, which impose big stresses that the body responds negatively to, the IWL plan imposes small stresses at monthly intervals the body responds positively to.

IWL was just ranked the Number 1 program for sustainable weight loss in an independent study published by the University of Wollongong.
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IWL helps you form healthy habits
that last a lifetime.

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Explain in more
detail your personal
health goals.

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We’ve got you covered. Sticking with something can be hard, but IWL participants say it gets easier over time.

My first thoughts on IWL was "this is going to take forever", my second thought "well, I guess I've been trying and failing for 30 odd years". To be honest, I didn't think IWL would be any different from every other diet I'd tried, and trust me, I've tried alot.

Here I am, 6 months down the IWL road and 6kg lighter. And so many other health benefits. My cholesterol and blood sugar are in the normal range, my skin is glowing, my energy levels have increased and I am feeling great. I feel fitter and healthier at 48 than I did at 28.

Steph De Sousa

MasterChef Contestant (2019) Author, Podcaster and Mother

IWL is used by leading hospitals. It was awarded the University of Sydney's People Choice Award.

It is approved by private health insurers. It is used by superannuation funds and life insurance companies.

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What is your lowest
adult weight?

What is your highest
adult weight?

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since you were at
your lowest weight?

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Are you regaining
weight following a
recent diet?

You’re half-way there! The next
few questions will further help us
personalise your program.

With more than 100 Five Star reviews you’re in good hands with IWL!

As a GP and preventative health expert, I fully support the Interval Weight Loss program. It is one of the few approaches to weight loss that is...

Rebecca M

The IWL program is not a diet; it's a comprehensive guide to living a healthy lifestyle, and I absolutely love it! For over 30 years, since becoming...

Karen Y

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Welcome to a plan that addresses your biology so you can prevent your body fighting the weight loss.
Dieting accelerates weight gain. In a 25-year study, the twin that dieted always ended up heavier than the twin that didn't diet.
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want to focus on
first with your IWL
plan?

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dietary restrictions
or preferences?

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Case Studies

Aisling Fleury

I never really struggled with my weight until my mid-30’s. After recovering from a significant mental health issue which resulted in rapid weight loss and then rebound weight gain (and then some and then some more), I knew I needed to do something. I tried some commercial weight loss programs and while I lost weight, I was always hungry and then regained it after the loss. It was so frustrating! I found IWL in a bookstore. From the start it seemed to make sense. I lost 10kg slowly in my first year and have kept it off for 4yrs. I recently had to do my first weight loss month in a long time but it was easy to return to my set point weight which I’d held for a long time. The principles of IWL are easy to maintain and integrate into everyday life. I am now a really organised meal planner and prepper which has helped with shopping and avoiding food waste. I have also found a way to incorporate exercise into my life. And found exercise I love! This has included taking up open water swimming and competing in my first open water swim race at Noosa this year. IWL isn’t a diet, it’s a change to your way of life - for the better.

Aisling Fleury

Brenton Johnson

I had always struggled with my weight regardless of how physically active I was, primarily due to overeating and poor food choices. When I hit my 30’s I moved into a less physical line of work and really ballooned to a personal highest weight of 115kg. I set about losing as much weight as quickly as I could using the techniques I had always used in the past: eat less and exercise a lot more. Needless to say, this never lasted long as I hated being hungry and had little idea of what I should actually be eating. A few months later I was diagnosed with a serious illness and was left paralysed. I still wanted to lose weight and had to get healthy in order to rehabilitate my body. I needed a solution that would suit my new (and existing) challenges with health and weight loss. I discovered the IWL Program and it immediately appealed to me. After nearly a year I am approaching my goal weight and have done so whilst still not being able to exercise to the extent I would like. I’ve learned to walk again and started a family and am finally feeling good about the decisions I make about my lifestyle, health and diet.

Brenton Johnson

Lorraine Bradwell

I never had to worry about my weight till I reached my mid 50s. Working in a high stress, long hours job, menopause and life in general all started to take their toll and I gained 14kg. I tried a variety of diet approaches, including calorie counting, intermittent fasting, commercial programs. They all worked - I lost weight but I couldn’t keep it off. One day my daughter told me about Dr Nick and his work, and gave me Dr Nick’s first book. From the first chapters I was sold. How many times had my friends and I said - “It seems as if there is a set weight your meant to be and you always return to that weight”. Initially I was frustrated because I didn’t see the big weight losses I was used to, but I stuck to it, confident that all that research can’t be wrong and soon I saw regular weight loss. Here I am, 5 years later, 12kgs down and comfortably able to maintain my new set weight. If I go off the rails, and I do occasionally, I know exactly how to get back on track. The online community and app is also very helpful. The best thing is, it’s not a diet, it’s a way of living, a marathon not a sprint, and it’s not even hard to do. Good luck, you won’t regret it - your life will be so much better for it.

Lorraine Bradwell

Ben Lindsay

After a relatively successful swimming career, I did what any swimmer does. I put on weight! After going up 19kgs from my swimming weight of 85kgs to 104kgs, I wasn't too happy. I went to the gym and exercised six times per week for 1.5 hours, but I would seemingly put it straight back on every time I lost the weight. I tried fasting to no avail - 18 hours a day at one point, I wasn't eating. I was hungry all the time. After picking up my first copy of IWL, I immediately applied the principles and have lost 16kgs (in 2kg increments) and maintained that weight loss over the past 1.5 years. Back under 90kgs, I am feeling healthy and fit again. I've never starved myself, and I am enjoying what I eat. I recommend IWL to every ex-swimmer I meet trying to lose that post-career ballooning.

Ben Lindsay

Bet Reichstein

My IWL journey started in January, 2020. I was feeling bad, having regained the weight and more from my latest diet, and now in my 60s, was feeling desperate to maintain health and mobility as the years advanced...I read about IWL and it gave me hope. I reached my weight loss goal (10kg weight loss) - this was a slow but steady journey as I learned to apply the IWL principles and form new health habits around food and activities. It is so liberating to be eating really normal healthy foods - no calorie or fat gram (etc) counting required. And I don't feel deprived or hungry, I feel so much better.

Bet Reichstein

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Limited offer: Try IWL FREE for 30 days

For a limited time, check out why we're an award-winning program at the University of Sydney and why we're supported by the Australian Government, superannuation funds and private health insurers.

No credit card details required.

IWL Plan

$29$0 /per month

For less than $1 a day,
you will have access to:
  • Personalised weight tracker
  • Step-by-step guide to the IWL plan
  • Daily habit tracker
  • IWL approved recipes
  • Access to IWL private community

IWL PLUS

$214.99$0

For less than $2.50 a day,
you will have access to:
  • All features in the IWL Plan
  • Individual coaching via telehealth with an accredited dietitian
  • One call per month with unlimited in-app chat or email support
  • Upgrade/downgrade any time

IWL Plan

SAVE 25%

$259$0

For less than $1 a day,
you will have access to:
  • Personalised weight tracker
  • Step-by-step guide to the IWL plan
  • Daily habit tracker
  • IWL approved recipes
  • Access to IWL private community

IWL PLUS

SAVE 25%

$649$0

For less than $2 a day,
you will have access to:
  • All features in the IWL Plan
  • Individual coaching via telehealth with an accredited dietitian
  • One call per month with unlimited in-app chat or email support
  • Upgrade/downgrade any time

All Done!
Thank you,

Sit tight as we build your individualised program based on thousands of IWL community members that have lost weight and kept it off.

1 centimeter = 0 feet 0.394 inch
IWL

Interval Weight Loss is Australia’s only scientifically developed weight-loss and wellbeing program, that’s proven to deliver lasting results.

Developed and tested by Dr Nick Fuller from the University of Sydney, IWL takes a stepped approach to weight-loss, that’s sustainable, resets your metabolism, and allows your body to return to a healthy weight without going into starvation mode.

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