What is it like having meal replacement shakes for a week?

I'm at the chemist having guilty flashbacks to being 16 years old on my tip toes reaching for a men's glossy magazine. I look left, then right… then reach to the top shelf for a 12 pack of Very Low Calorie Diet (VLCD) banana flavoured meal replacement shake packets.

Why? I like physical challenges for the sake of experience. Every health and fitness journey is a good one if it breeds knowledge. I've done the fasting, diet pills, CrossFit challenges, and more.

So, with replacement shakes, I've decided to dip my toes in the end of the pool that I've always told my clients to stay away from – for the experience.

Here's the skinny on my five days of Shake Week.

Before the shakes

The plan

Spaced out mentally; walked out into traffic, almost hit by a car. Very tired.

All food and drink is being replaced by one packet of banana flavoured powder stirred into 200-250ml of water, three times per day for five days. I'll drink another two litres of water per day to ensure I'm hydrated.

The industry

From the global giants to the Aussie home grown brands, there are meal replacement bars, shakes, chips, and soups in many flavours. The dietary supplements industry is booming, and globally it's predicted to be worth USD$131 billion ($172 billion), with women making two thirds of all supplement purchases.

The cost


Four days' worth (12 packets) of banana flavoured powders costs $35.95. Add tap water, and by adding a fifth day, $45 is my food expenditure for a five day period. At $9 per day, that's $3 per shake – cheap as meal replacement chips.

The ingredients

One shake packet contains well over 30 ingredients; I stopped counting because all the scientific jargon started to look the same. They are manufactured in Europe, so meal replacement is the antithesis of the 'eat local, eat healthy' farm-to-plate movement.

The contents

Three packets for breakfast, lunch, and dinner is just over 600 calories (2,600kJ), 53 grams of both protein and sugar. That's a serious calorie / protein deficit compared to my (or any adult's) normal, daily intake.

The exercise

With so little energy going in, I'm going to keep my movement pretty simple. I'll commit to some outdoor running with clients along with a daily, simple circuit of 100 skips, 15 push ups, 15 squats, 15 sit ups – five rounds.

The experts

Anna-Jane Debenham and Alexandra Parker are dietitians at Sydney's The Biting Truth. I asked two questions:

Do you recommend these diet replacement shakes? Only for clinically obese patients. You'll be restricting carbs, and therefore burning fat stores which puts your body into ketosis. It's not sustainable for the average individual, and the weight lost will come straight back on. I don't recommend it for you.

What can I expect this week? In the first couple of days you'll feel fatigue, headaches, lack of concentration, nauseous, and incredibly hungry. You'll be making massive changes to your digestive system. This won't be a pleasant five days.

The concerns

My energy for my workouts. Energy for my personal training clients. No glass of red at night. No beers with the lads at poker. No chocolate. No salmon and veggies. No sex? No avocado on toast with eggs. The monotony. The hunger. The no socialising over a meal. The unknown.

After the shakes

Somehow, I made it. Here's a brain dump / diary of Shake Week:

Day 1

Shakes taste okay – nothing great, nothing terrible. Energy is fine, but by 4pm 'hunger' settles in for the remainder of the day / night.

Day 2

Hunger digs its dirty heels in. Need food. Workout was at 80 per cent energy. Starving.

Day 3

Hunger intensifies. I'm Googling Sydney's best burgers for final day. Slack workout. Walked to get bathroom goods at the supermarket, and I came home without two items – forgetful. Crap workout. Nap required. Have not pooped since Day 1.

Day 4

Hunger remains. Bought five group discount meal vouchers. I'm a consumer of food I can't yet eat. Spaced out mentally; walked out into traffic, almost hit by a car. Very tired. Shakes bore me, so no more. No workout.

Day 5

The thought of food is all consuming. Made it to the afternoon, then finally ate – food never tasted so good. As I sit over my first meal with sauce covering one third of my face, I ask myself these questions:

Would I recommend Shake Week? No.

Did I cheat? Yes. A few glasses of wine. Bad idea.

Did I lose weight? Yes. Plenty.

What did I eat first? You can view that HERE.

The verdict

Real food, portion control, and exercise – it's boring and cliché, but it's the only journey for weight loss and maintenance. Forget the shakes.

Meal replacement shakes, bars, and more. Have you ever tried them? Successful or not? Let us know in the Comments section.

Passion for lifestyle change is the cornerstone for everything Michael Jarosky does. A Sydney-based personal trainer, he cajoled thousands of Executive Style readers to undertake his 'Cut The BS' diet, and champions a charity weight-loss event, Droptober.

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