Bone health isn’t just a concern for older people. We need to build and maintain a strong skeleton from our teenage years says Peta Bee
WE are all aware that a sedentary lifestyle and unhealthy diet will take its toll on our waistlines and our hearts. But do you ever stop to think about the effect your lifestyle might be having on your skeleton?
Our bones are getting increasingly fragile. In Ireland, 25% of men and 50% of women aged over 50 have osteoporosis, the condition in which bones weaken to the point they are vulnerable to fracture, but according to the Irish Osteoporosis Society, only 15% of cases are diagnosed leaving many at risk of breaking a bone because of the disease.
Michele O’Brien, a spokesperson for the society, says “it is preventable and treatable in the majority of people”.
How best to boost your bone health? Here, we provide expert advice:
It’s during the teens that your body builds most of the bone that must sustain it for the rest of your life. Bone mass spirals during growth spurts that occur age 12.5 in girls and 14.1 in boys and experts say that the total amount of bone accrued in the two years when teenagers are growing fastest is similar to the amount of bone lost in the three decades between ages 50 and 80.
Exercise: Bone is a living tissue that reacts to increases in loads and forces by growing stronger and it has been shown that much time sitting in front of screens is linked to a weaker skeleton. Now is the decade you must get up and move as much as possible.
Include weight-bearing activity – the kind that involves shifting your own body off the ground with some force as you do when you run or jump. This kind of impact changes bones at cellular level by stimulating bone-forming cells (called osteoblasts) and encouraging them to grown bigger and stronger. Anything from running and football to circuit training and tennis is good.
Diet: Between the ages of 11-18, the Irish Nutrition & Dietetic Institute recommends that boys and girls need an intake of 1200mg of calcium daily which can be obtained from milk, cheese and yogurt but from alternatives such as soya and almond milk only if they are fortified – which many are not.
Findings from the National Children’s Food Survey in Ireland suggest that up to one-third of five to 12-year-olds may have inadequate calcium intakes, a habit that might continue into the teens.
Food is better than supplements as it provides additional bone-healthy nutrients such as phosphorous, magnesium and vitamin K.
Don’t eat dairy? Try consuming more leafy greens - kale and cabbage not only contain around 56mg of calcium per 75mg serving, but also pack in bone-building vitamin K. And eat an orange over an apple - you will add 75mg of calcium to your daily tally.
Peak bone mass is reached in your late twenties, but that doesn’t mean it is too late to adopt a bone-boosting strategy. Experts now know that bone is responsive to diet and exercise throughout life and you can improve bone density substantially even as you get older throughout your life.
Exercise: Try high-intensity training, or HIT, could help. Researchers at the Universities of Exeter and Leicester showed that women who did 60-120 seconds a day of weight-bearing HIIT, including jumps and skips, had 4% better bone density than those who did less than a minute. And those who did over two minutes of high impact HIIT daily had 6% stronger bones.
Diet: Intense dieting can play havoc with bone development. It has been shown to disrupt growth hormones and hamper the action of osteoblasts resulting in bone loss. During this decade (and though to age 64), it is recommended both men and women consume 800mg of calcium daily.
According to the National Adult Nutrition Survey of Ireland, as many as 16% of women in Ireland are consuming less than that amount, so make sure you get enough. Pulses are a good source of calcium and a 100g serving of these provides 8% of an adult’s daily requirement. Or swap tuna for tinned sardines - the soft bones are a tremendous calcium source. Half a tin (60g) will give you around 250mg of the mineral.
A drop in levels of testosterone from middle age onwards can have a dramatic effect on bone density. Research presented at the American Urological Association Annual Meeting in 2015 suggested that “low testosterone is one of the more established risk factors for osteoporosis in men” and a study showed that 39% of men aged 50 with low testosterone levels also had low bone mineral density while 5% of them had osteoporosis.
Exercise: Many men who reach middle age discover they have sore and aching joints, so take up swimming or cycling as preferred forms of exercise. However, their lack of resistance means they are not bone-friendly. Weight training is much better.
When sports scientists at the University of Missouri asked middle-aged men to complete either a 60-120 weight lifting routine or a star-jumping routine for a year (and also take supplements of calcium and vitamin D), they found the bone mass of the whole body and the spine increased with both activities and was maintained at 12 months, but that only the weights led to improvements in hip bone density.
Diet: Scientists at Harvard Medical School found that men with more fat around their belly had weaker bones than other men. In a 2018 study published in the Journal of
Bone Mineral Density,
researchers from the University of Reading found men over 50 seem to benefit most from dairy consumption, having boosted bone strength.
For women, who have smaller bones to start with, the rapid increase in bone loss that typically occurs in the late 40s and early 50s around the menopause when their levels of the bone-protecting hormone oestrogen plummet, is an added risk for osteoporosis.
Exercise: Any activity that involves jumping and twisting and that puts more pressure on bones than gravity is good – that includes squash and Irish dancing. Japanese researchers showed that jumping as high off the ground as possible 10 times daily, three times a week for six months, increased bone mineral density in their legs and the lower spines.
Diet: Aim for 800mg of calcium a day adulthood, although you should consume 1200mg if pregnant. A Mediterranean style diet – packed with vegetables, oily fish, grains and olive oil – is the best approach as a study presented at the Endocrine Society’s annual conference this year showed it helped prevent osteoporosis and fractures in women. In a trial published by Pamela Hinton, professor of nutrition and exercise at the University of Missouri (August 2018), it was shown that soy protein added to the diet of laboratory animals increased their bone density. “Adding some tofu or other soya, for example, foods found in vegetarian diets could help strengthen bones,” she said.
There there is plenty you can do to maintain bone health, even in this decade.
Diet: Eat more plain yogurt. Eamon Laird, a research fellow at Trinity College Dublin discovered that people aged 60 and over who ate it daily had a 3-4% increase in bone mineral density.
“Yogurt is a good source of micronutrients, B vitamins and calcium,” says Laird.
“And it contains protein and probiotics as well. We think it could be a combination of these things that has the beneficial effect.”
Exercise: A review of 35 studies found that tai chi can be beneficial for some people, improving muscle strength, flexibility, bone mineral density, and balance and yoga has also been found to improve bone health in over 60s with osteoporosis or its precursor, osteopenia.
At this age weight training is a must. A study published last year in the
Journal of Bone and Mineral Research
showed that twice-weekly 30-minute sessions of high-intensity weight training increased lumbar-spine bone-mineral density by nearly 3% over eight months in a group of post-menopausal women with low bone density, compared with a loss of 1.2 % for a control group of women who did low-intensity workouts.