Every week another new diet seems to pop up.
From juicing to eating only raw foods, from special smoothies to living off kale for a week, each one claims to be the Holy Grail of weight loss.
Clean living and eating the latest ‘super foods’, we’re told, is not only good for us but fashionable too, with celebrities extolling their latest diets on social media.
But do these fad diets have a downside for our future health?
During childhood and our teenage years, we ‘bank’ our bone strength, which will keep our skeleton healthy for years to come.
The most important way of doing this is to eat a calcium-rich, balanced, healthy diet.
But as more young women try the latest single-food-group or starvation diets, is there a hidden cost to maintaining the perfect body?
Dr Sarah Schenker, registered dietician and nutritionist, says that following a particular fad diet in the short term won’t usually cause any major damage.
‘Problems can arise,’ she says, ‘when a person jumps from fad diet to fad diet, doing one after another for months and years.
If you’re doing several diets a year that restrict certain food groups, this can have long-term implications, which you might not notice now but will in future.’
One effect can be anaemia from a lack of iron. This can cause tiredness, pale skin and shortness of breath.
Another complication can be osteoporosis — where bones become brittle and fragile and can break easily.
Osteoporosis nurse consultant Sarah Leyland, from the National Osteoporosis Society, says: ‘If you make huge changes to your diet over a long time you could be compromising bone health.
‘We know from research that your intake of calcium and a healthy, well-balanced diet is important for maintaining bone density — and long-term exclusion of certain important foods can compromise that.’
Sarah says that the most obvious sign you might be affecting your bones is if your weight loss leads to your hormone levels dropping and your periods stopping.
‘We know that this is linked to osteoporosis,’ she says.
Dr Schenker agrees: ‘Following extreme diet after extreme diet can mean you aren’t getting enough of the foods you need — such as foods containing calcium.
‘The trouble with calcium deficiency — which can lead to osteoporosis — is that, early on, you can’t feel the effects. You don’t know what damage has been caused until you’re much older.’
She adds: ‘The first sign can often be a broken bone from a fall, by which time it’s too late to repair the damage.’
Dr Schenker says that the only way to tell if your bones are becoming damaged is to have a specialist bone density scan.
‘But these are not routine and you’d probably have to book it privately,’ she says.
Sarah Leyland stresses that in order to protect future bone health, women need to rethink what ‘healthy’ means.
‘It’s hard searching for the “perfect diet” when it doesn’t exist,’ she says. ‘Just be aware that eliminating food groups long term can have damaging effects. Our main message for bone health is balance.’
Dr Schenker adds: ‘Women have to weigh up what is most important — looking good now or their long-term health.
‘Over time women need to accept their body shape as it is. Concentrate not on “wobbly bits” or things you don’t like — instead tell yourself “I’m strong” or “I’m healthy” and feel proud about that.’
So if you have dieted for years, can the damage be halted?
Dr Schenker says: ‘You could take a supplement for calcium and vitamin D. But then you need to think about changing your mindset about food.
‘If you’ve always been terrified of eating carbohydrates, look at different carbohydrates that we know are good for us — such as quinoa or brown basmati rice.
‘If you add these things back into your diet — along with varied fruit and vegetables — you’ll gain a range of health benefits both short and long term. Women need more iron than men and post-menopausal women need a higher dose of calcium.’
Sarah Leyland says: ‘It’s never too late to start thinking about bone health. Safe exposure to sunlight increases our absorption of calcium, but in the winter months you can top up with a calcium and vitamin D supplement or increase your intake of vitamin D-rich foods such as egg yolks and oily fish.’
Edited by Julie Cook