He’s the 55-year-old health guru who counts Sir David Beckham, Kendall Jenner and even Cristiano Ronaldo among his clients. Gary Brecka claims to have ‘reversed his biological age’ to that of a 20-year-old, significantly reducing his risk of developing old-age diseases such as diabetes and dementia.

Brecka – who has about 4million social media followers – is part of a growing field of influencers known as ‘biohackers’, who claim that lifestyle changes can turn back the body’s clock.

It’s a lucrative line of work too. The field, also known as longevity medicine, is worth around £18.5 billion worldwide.

So how does Brecka keep himself young? His daily routine is not for the faint-hearted. It includes ice-cold plunges, hydrogen baths, hyperbaric oxygen chambers and red light therapy.

To learn his biohacking secrets, Brecka charges clients close to £40,000 for an hour’s one-on-one session, while he sells an at-home DNA test for £349 which is said to reveal your nutrient and energy levels, and your biological age.

But, perhaps surprisingly given his daily routine and his lucrative coaching business, Brecka claims that you don’t need to spend tens of thousands – or even hundreds – of pounds to reverse your biological age. In fact, he claims that a few cheap and simple lifestyle changes could be enough.

‘I was a mortality researcher for a large life insurance company for almost 20 years, and what we did was analyse medical and lifestyle data to know people’s specific mortality risk,’ Brecka told The Mail on Sunday. 

‘If I was to sum up what I learned in that entire career, it would be the reason why much of humanity isn’t living healthier, longer lives is because of modifiable risk factors – dietary and lifestyle changes.

‘It isn’t down to people not using red light therapy, hyperbaric oxygen chambers or following a specific diet. It’s overall choices that impact health for the better – or worse.’

So what is his advice – and is it worth following? We spoke to some leading ageing experts to see how his claims stack up...

IGNORE RED MEAT SCARE STORIES... IT’S HEALTHY

Animal fat is crucial for a long life because it is packed with vital nutrients, says Brecka.

The American says he eats ‘lots’ of grass-fed beef – typically several times a week – arguing it is filled with nutrients that are vital for muscle and brain health.

Brecka believes that health warnings about red meat are misguided. Instead, he believes ill-health is caused by processed meats such as bacon and ham, made with artificial chemicals.

‘Can you eat red meat? Absolutely, it’s not killing you,’ he says. ‘What’s killing you is dosing yourself with processed foods.’

But he is clear that meat is just one part of a varied, natural diet, which also includes plenty of vegetables, healthy oils, fish and eggs. He argues that restrictive diets of any kind – including veganism – are bad for the body. And experts agree on this front.

Studies show many vegans are deficient in nutrients such as vitamin B12, which is crucial for healthy DNA production.

Meanwhile, a carnivore diet which excludes vegetables, nuts and pulses, has been shown to raise cholesterol levels – increasing chances of heart problems – and also lead to major deficiencies in nutrients including vitamin C and fibre, both of which are needed for a functioning gut and immune system.

But experts take issue with Brecka’s claim on red meat. ‘Regularly consuming red meat is associated with an increased risk of colon cancer and type 2 diabetes as well as heart disease,’ says Dr Federica Amati, a research fellow at Imperial College London and head nutritionist at the diet app Zoe. ‘If you like red meat, you should eat it in moderation and keep portion sizes small.’

EVERY MORNING TAKE DEEP BREATHS OUTSIDE 

Spend 30 minutes every day practising breathing exercises to lower stress levels, says Brecka.

One such routine is called box breathing, or four-square breathing. It involves inhaling for four seconds, then exhaling for four seconds, repeated for half an hour.

Brecka argues that doing these exercises outside in the morning exposes the body to natural light, which helps to regulate our internal 24-hour clock – the circadian rhythm which regulates sleep and the release of hormones.

‘I often practice breathwork outdoors,’ says Brecka. ‘Deep breathing to bring oxygen into my body and relieve any stress.’

Experts say breathing exercises could boost lifespan by helping people avoid dangerous diseases.

One Harvard University analysis of more than a dozen studies in 2023 found that patients who regularly practised controlled breathing saw their blood pressure and heart rate reduced as their stress levels lowered.

The researchers said breathing exercises may be an ‘important’ tool to bring down high blood pressure – an issue that greatly increases the risk of heart disease and affects around a third of British adults.

Heightened stress levels have also been linked to type 2 diabetes, a weakened immune system and even dementia. Significantly, experts also agree that there is strong evidence that sunlight helps regulate the body’s circadian rhythm, which, in turn, slashes risk of life-threatening disease.

One Brazilian study this year concluded that exposure to morning sunlight was a key factor to ensuring a good night’s sleep. And multiple studies show that people who work night shifts, which disrupt the circadian rhythm, are as much as a third more likely to suffer deadly heart disease.

‘As we age our circadian rhythm gets worse, and this can impact our sleep and overall health,’ says Professor Dame Linda Partridge, an ageing expert at University College London. ‘A good blast of sunlight in the morning can help counteract this.’

FASTING FOR UP TO 16 HOURS EVERY DAY

Going hours without food could be the answer to avoiding life-shortening diseases such as dementia, Brecka claims.

He argues that fasting for up to 16 hours a day not only prevents overeating but also helps rid the body of ‘zombie’ cells.

These cells, he claims, build up in the body, increasing chronic inflammation that triggers diseases of ageing such as diabetes, arthritis and Alzheimer’s.

‘Intermittent fasting can be the best thing that you ever do for yourself,’ says Brecka. However, he does recommend that people considering fasting should get their blood sugar levels tested by their GP first, because fasting when levels are low can be dangerous.

For those healthy enough, Brecka also recommends an even more extreme form of fasting – a three-day fast. This involves consuming nothing but water, bone broth and electrolytes for 72 hours.

Brecka insists the practice – which he says should be done under expert supervision – can supercharge the removal of zombie cells from the body.

Experts say that intermittent fasting has numerous health benefits. Earlier this year, a major Australian paper, which analysed 56 studies, found the practice reliably lowered body weight and blood pressure, in turn cutting the chances of heart disease and strokes.

However, some experts say that there are no human studies that prove this is due to the body ridding itself of so-called zombie cells. Instead, they argue, it is more likely due to the fact that people who practice intermittent fasting, on average, consume fewer calories, meaning they are less likely to be obese – one of the leading causes of ill-health.

Other experts say a three-day fast would not be the right choice for most people.

‘There is some evidence that fasting improves health, but the effect is limited,’ says Prof Partridge.

‘And a three-day fast would be impractical for most people, so it’s not something I would recommend.’

EXERCISE FOR 20 MINS BEFORE BREAKFAST 

Brecka argues that exercising after fasting can help the body burn more fat, further lowering the risk of ill health.

However, he adds that intensive exercise is unnecessary – just a 20-minute burst of activity can make a big difference. He recommends yoga or a brisk walk before breakfast.

‘Working out before eating means your body uses stored fat for fuel,’ Brecka argues. ‘And it gets your blood flowing and sets you up for the day’.

He also says that strength-based exercises – such as weight-lifting – are also crucial to strengthening the joints, muscles and bones, preventing old-age frailty.

Exercising on an empty stomach – also called fasted exercise – is a growing field of research.

Early studies, including a 2025 paper published in the medical journal Nature, found that those who perform fasted exercise may lose more fat than those who do not.

However, the study concluded that more research is needed to prove this is true.

Brecka’s claim that all that is needed is 20 minutes of low-intensity exercise every day – equivalent to 140 minutes a week – is roughly the same as official NHS advice.

The Health Service suggests either 150 minutes of moderate-intensity exercise a week or 75 minutes of vigorous or intensity activity a week.

There is also strong evidence that, as Brecka claims, strength-based exercises can stave off old-age weakness.

A major analysis, published in 2022, found that performing any amount of strength-­training cuts the risk of deaths from any causes, including cancer and heart disease, by as much as a fifth.

‘There’s nothing controversial here,’ says Prof Partridge.

‘Strength training really is key to fighting off frailty. Whether it’s pilates or weights, it will keep the body healthy.’

WILL A SLEEP MASK EXTEND LIFE?  

Always wear an eye mask to sleep – or risk knocking years off your life, Brecka claims.

Over time, he argues, poor sleep affects the body’s ability to function properly, speeding up ageing and raising the risk of deadly diseases.

For this reason, Brecka cools his room to 20C (he lives in Florida) and sets an alarm to go to bed – usually no later than 10pm.

However, most crucial, he claims, is wearing an eye mask. ‘You’d be shocked how little light it takes to raise your cortisol levels, which wakes you up,’ he says. ‘All you need is something to block light – a cotton mask will do.’

Experts say Brecka is right to put so much emphasis on the importance of good sleep. Many large-scale studies have all reported that the shorter someone sleeps, the shorter their life. Over time, poor sleep can lead to high blood pressure and other problems.

But experts say there is little evidence eye masks are crucial. ‘As long as you’re sleeping in a dark room, that should be enough,’ says Prof Linda Partridge of University College London.