To anyone with even a passing knowledge of social media, the pose is instantly recognizable.
The lower back dips into a pronounced arch, hips tipped forward, buttocks pushed out and chest lifted high.
It creates striking, hourglass-like curves and the illusion of long, slender legs.
And it’s everywhere: models, fitness influencers, celebrities and just about anyone on TikTok and Instagram aspiring to the look adapt the same pose. Most often used while standing in photos, the trick even works while seated.
It’s even been given a nickname: the ‘Instagram posture’ – or, more bluntly, ‘Instagram butt.’
But health experts warn that behind the flattering angles on their social media feeds lies a more worrying phenomenon.
The pose is a textbook example of something called anterior pelvic tilt, a postural position in which the pelvis tips forward, exaggerating the arch of the lower back and pushing the hips and buttocks backwards.
While the body can move in and out of this position without harm, specialists say that repeatedly standing, training or unconsciously defaulting to it can, over time, train the body into a permanent imbalance.
The pelvis tips forward, exaggerating the lower back arch and pushing the hips and buttocks backwards. (Pictured: fitness influencer Jen Selter and actress Bella Thorne)
Real Housewives of New York City star Bethenny Frankel, 55, is pictured at the Sports Illustrated Swimsuit Runway Show last month in Florida, posing with an anterior pelvic tilt
Kendall Jenner taking a behind-the-scenes selfie in the mirror while shooting an advert for sister Kim Kardashian’s SKIMS underwear brand
So, what begins as a clever hack to enhance a silhouette can gradually alter a person’s natural posture – placing strain on the lower back, hips and even knee joints.
Dr Ashley Katzenback, an orthopedic physical therapist at Cape Cod Physical Therapy in Massachusetts, told the Daily Mail: ‘Standing in an anterior pelvic tilt is not inherently harmful, but it can lead to muscle imbalances.
‘For example, the abdominal muscles can become stretched beyond their normal resting length, making it harder to keep the ribcage and pelvis properly aligned.
‘This can give the appearance that the stomach is protruding forward.
‘Over time, increased strain on the joints can cause them to loosen, reducing their ability to effectively support the bones. Without that support, the risk of sprains, dislocations and fractures may increase.
‘Constant shifting of the bones also places wear and tear on the cartilage – the connective tissue that protects joints – raising the risk of developing osteoarthritis later in life.’
And the concern is understandable.
Arthritis – the umbrella term that includes osteoarthritis – is already one of the most widespread chronic conditions in the US, affecting more than 53 million adults, or around one in five.
Osteoarthritis alone impacts an estimated 32.5 million Americans, making it a leading cause of disability.
The problem is only set to grow. Health officials warn that the number of Americans living with arthritis could surge to 78 million by 2040.
While the condition is still most common in older adults, it is no longer confined to them.
Around three to four percent of 18 to 34-year-olds already have arthritis, pointing to a worrying trend driven in part by lifestyle factors and joint strain.
Meanwhile, back pain is also a growing problem in the US, with studies suggesting that nearly four in ten adults report it in any given three‑month period.
It is more common in older people, but experts warn diagnoses are increasingly being seen in younger adults, with research pointing to a rising overall burden of low back pain among those aged under 40.
While ‘Instagram butt’ might be a new factor behind the trend, it’s far from the only risk.
As Dr Sherry McAllister, a chiropractor and president of the Foundation for Chiropractic Progress, explains, anterior pelvic tilt is often the result of modern lifestyles.
‘It typically develops due to a combination of factors, including prolonged sitting, poor core strength, pregnancy and repetitive movements that create muscular imbalances,’ she said.
Specialists say that repeatedly standing, training or unconsciously defaulting to the pose can, over time, train the body into a permanent imbalance. (Pictured: Kylie Jenner)
It’s most often adopted while standing in photos, but the trick even works while seated. (Pictured: Kim Kardashian)
Over time, tight hip flexors and weaker glutes can pull the pelvis forward, increasing strain on the lower back.
‘Many of today’s daily habits encourage the body to adapt to positions it was never designed to maintain for hours at a time,’ McAllister added.
Long hours spent sitting at a desk, driving or looking down at phones and laptops can all contribute to the problem.
Maintaining core strength and moving regularly throughout the day can help support the spine’s natural curve and reduce strain on the lower back and surrounding nerves.
While occasionally standing in this position is unlikely to cause harm, McAllister said regularly defaulting to it may lead to low back discomfort, muscle fatigue and hip soreness.
Dr Mariam Zakhary, a physical medicine and rehabilitation physician and clinical advisor at Ikon Recovery Center in New Jersey, told the Daily Mail that deliberately adopting an anterior pelvic tilt for photos ‘does not seem to be damaging in an otherwise healthy individual.’
‘There is, however, great concern if someone continues to stand, walk or exercise with an abnormal amount of anterior pelvic tilt,’ she added.
To counter it, Zakhary recommends strength training, particularly exercises that target the core and glutes, helping to prevent surrounding muscles from weakening or overstretching.
Hip mobility work, including movements such as hip circles and sidesteps, can also help guide the pelvis back into a more neutral position.
‘If you are spending a lot of time in an anterior pelvic tilt, then you need to stretch in the opposite direction — for example with child’s pose or pelvic circles, almost like a hula hoop,’ added Dr Ashley Katzenback, an orthopedic physical therapist.
‘Like everything else, there has to be balance in our bodies.’
