From new dad to new energy: How Karl lost 24kg and reclaimed his health

When Karl van Zwol and his wife welcomed identical twin boys into the world, life changed overnight — in the best possible way.

But as any parent knows, joy often comes hand in hand with exhaustion.

Now 53, the Design and Technology teacher from Karratha in Western Australia found that adjusting to life with newborn twins meant exercising less, eating more, and putting his own health on the back burner. Over time, the weight crept on.

By the time Karl reached 112kg, he no longer felt like himself.

“I struggled to get motivated,” he says. “My boys ran rings around me, and I felt constantly lethargic.”

Things escalated during the second half of 2024, when Karl’s health steadily declined. He felt generally unwell for months, and eventually, it culminated in a hospital stay with diverticulitis — a wake-up call he couldn’t ignore.

The wake-up call he couldn’t ignore

“I knew I had a high amount of visceral fat, and that’s not something you mess around with,” Karl says. “Especially when you’ve got young kids.”

For Karl, this wasn’t about fitting into smaller clothes or chasing an unrealistic ideal. It was about being present — and healthy — for his family as he got older.

His wife, who had also gained weight since the twins arrived, had started exercising again and encouraged Karl to do the same.

“It was very much a ‘now or never’ moment,” he says.

Choosing a program that made sense

Karl had tried weight loss programs before. Some were effective but far too expensive. Others, like intermittent fasting, simply didn’t suit him.

“I enjoy eating,” he says plainly. “That approach just wasn’t sustainable for me.”

When Karl searched online for ways to reduce visceral fat, the CSIRO Total Wellbeing Diet kept appearing in his results. After looking into it, the decision felt straightforward.

“I chose it because it’s backed by CSIRO research, the cost of membership was covered by my health fund, and the food comes from the supermarket — not from the company itself,” he explains.

The program’s strong scientific foundation, affordability and real-world practicality gave Karl confidence that this wasn’t just another short-term fix. It was a lifestyle change he could stick to — joining thousands of members who have achieved lasting success, as reflected in the program’s overall results.

Structure, knowledge and the right tools

From the beginning, Karl found the CSIRO Total Wellbeing Diet app to be a major source of support.

“The meal planning tools were excellent,” he says. “They helped me understand portion sizes and balance, rather than just guessing.”

He also credits the program’s ‘energy in versus energy out’ feature as a game-changer.

“It empowered me with the knowledge I needed to eat a balanced and appropriately sized diet,” Karl explains. “Once I understood that, everything started to click.”

The personalised approach — including flexible meal plans and practical digital tools — helped Karl stay consistent, even with a busy work schedule and family life. While finding time to prepare meals was sometimes challenging, the clarity and guidance kept him on track.

Over 10.5 months, Karl lost an incredible 24kg, reaching a weight of 88kg — and more importantly, feeling healthier and more capable than he had in years.

A more active, capable life

Today, Karl’s life looks very different.

Most evenings, he heads out for an hour-long mountain bike ride, something he now genuinely looks forward to. His meals are simple, satisfying and nourishing — from berries with yoghurt and cereal for breakfast, to easy wraps for lunch and fresh fish-based dinners.

“I love the healthy food I eat now,” he says. “It makes me feel better.”

The changes have also carried over into everyday tasks. Karl spends a lot of time working on his car — a hobby that often requires climbing underneath and getting back out again.

“Before I lost the weight, that kind of work was exhausting,” he says. “Now, I can do it easily.”

While Karl hasn’t overcome a specific diagnosed condition, the difference in how he feels is unmistakable.

“I feel really healthy now,” he says. “I’m enjoying life again.”

More than weight loss

For Karl, the biggest impact hasn’t just been physical — it’s been emotional and relational.

“My wife is really stoked,” he says. “I’m more mobile, fitter, and just feel better about myself.”

Looking ahead, Karl’s goals are refreshingly grounded. He wants to stay healthy as his boys grow up, enjoy the final third of his working life, and eventually retire feeling strong and capable.

“It’s about looking after my family and being able to enjoy life,” he says.

Karl’s advice for anyone thinking about starting

After his journey, Karl’s advice is simple and practical:

“Enjoy the journey. Don’t get caught up in the number on the scales. Use it as an opportunity to change your lifestyle — not just lose weight.”

With its science-backed approach, flexible meal plans, practical tools and affordable pricing, the CSIRO Total Wellbeing Diet gave Karl the structure he needed to make lasting change.

And as his story shows, when you focus on health first, the weight loss — and the energy to keep up with life — can follow.