Did you know that you get a new skeleton every eight years? (for more information on bone turnover and what influences it click here) Just like your skin, bone is a living tissue and is constantly being renewed and replaced. Our commonly held view is that bone is a hard brittle material that does not change needs to be revisited in light of ongoing research into bone health and the new ways it can be improved and influenced. The fact is that bone is an incredibly changeable tissue explains how it is able to adapt to different stresses placed upon it (click here for some background on this aspect of bone biology). Indeed its very shape and thickness can alter in response to different stimuli. For example, a professional tennis player will place so much stress through his right arm bones that in time the bone cells become more active and remodel the architecture of the forearm bones making them thicker and stronger. The skeletons ability to change and adapt is a key factor in maintaining bone health and an equally important aspect in certain diseases. This has been dramatically illustrated in certain extreme environment. Studies performed by NASA clearly show that space flight had severe complications on the skeleton. Due to the weightless nature of the body in space, gravity cannot act on the skeleton, with an end result of a rapid thinning and weakening of bone. Special bone loading exercises and equipment have to be used to help those living and working in zero gravity maintain their bone and muscle health as this image shows keeping bone health in top form on the International Space Station is not without its complications and fuss! Otherwise ultrafit Astronauts develop osteoporosis, the thin bone disease commonly associated with older or menopausal women! Interestingly this is no news to the Russians who have been working with manned space stations for years. The Russian Cosmonauts (click on the manual download option if you follow this link) routinely take vitamin K supplements. This nutrient is known to boost bone health by stimulating the growth of the bone proteins needed to support the calcium and other minerals found in the skeleton. For those interested in the nutritional demands and requirement in zero gravity click here for an abstract on the subject, if you click on the option “PDF 334 KB” on the right side of the new screen that pops up you can get a fascinating download on this subject.
Vitamin K has only relatively recently become a hot topic in the osteoporosis world outside Russia. Despite it’s potential interaction with blood thinning drugs such as warfarin (those on blood thinners should avoid vitamin K) vitamin K is a very safe and well tolerated nutrient. Studies indicate that taking certain forms of vitamin K are associated with a 77% reduced risk of hip fracture and an 60% reduction in vertebral fractures. The mechanism behind this dramatic finding appears to involve the bone protein osteocalcin. Without a good framework to act as a guide minerals simply cannot bind on to strengthen the bones.
Feeding the bones
Bones demand feeding in a special way for a lifetime of optimal health. Certain dietary factors are known to have a bad effect on bone health and may actually increase your risk of developing thin bones in later life. Processed foods, excessive sugar, alcohol, fizzy drinks, cigarettes, coffee all can have a detrimental effect on the bones. Many pre-made ready meals come loaded with added salt. Salt has the effect of making food tasty but the extra salt (sodium) not only plays havoc with your blood pressure and fluid balance but it can also increase the calcium loss significantly. Estimates have this loss in the region of 52grams of calcium if your sodium intake jumps from 1000mg per day to 4000mg. Eating a healthy and balanced diet is such a common phrase we tend to forget how important it is to tissues we don’t normally think about; be honest, when was the last time you thought about the health of your hip bone?
When it comes to foods there is a great deal of controversy. Many authorities list milk and dairy products as key sources of calcium needed for healthy bones while some raise the worry that dairy derived calcium may actually have a detrimental effect on the skeleton. The Vegan society has some interesting information on this rather controversial subject, click here. Protein is another potential point of confusion. We need adequate protein for bone to make the basic scaffolding onto which minerals are deposited. High protein intakes, however, are associated with an increased los of calcium from the body, click here for come additional background information. Beans and pulses may offer a solution in this situation. A 100g portion of beans (dry weight) has a neutral effect on calcium balance while a similar amount of animal derived protein may cause a loss of calcium from the body. Increasing your intake of beans and pulses will boost your protein intake and have no adverse effect on calcium balance. To reassure you though, a moderate intakes of animal products, as part of a balanced diet, will not cause a drastic enough loss when off set against the additional calcium intake of that meal. Most balanced diets offset losses with the gains.
While we are on the subject of absorbing calcium it would be a good idea to mention the importance of vitamin D, or specifically vitamin D3. Acting in a hormone-like way, this key vitamin not only boosts the immune systems ability to keep us fit and well, it plays a pivotal part in the absorption of calcium from the gut. Many of us simply don’t get enough vitamin D3 from sunlight exposure and there is a negligible amount on offer from the diet. Contrary to the commonly accepted idea, milk offers no vitamin D. This confusion may have originally come from America where milk is fortified with added vitamin D, but this is not the case in the UK. Taking extra vitamin D3 would appear to be the answer for all of us, especially over the dark winter months.
To appreciate how important it is to keep bones well fed it is worth understanding how the nutritional needs change with age. During infancy our bodies are very efficient at absorbing calcium, especially from breast milk. A baby can absorb 66% of the available calcium from breast milk compared to less than a 40% absorbency rate from infant formula milk. During childhood (between one and ten years of age) the efficiency of calcium absorbency reduces to about 35%, but by adolescence it rises again to 40% to match the growth spurts associated with this phase of life. Crash diets and eating fads can seriously reduce the nutrient intake over this crucial phase of skeletal development. By the time adulthood is reached much of the final skeletal form is set. The peak bone mass is achieved by 35 years of age. Calcium absorption reduces slightly to about 30%. Adulthood also brings with it other natural diversions as far as calcium goes. It has been suggested that during the first three months of pregnancy, maternal bone density reduces as well as during lactation. During the menopause a complex interaction between hormones, calcium and other trace elements occur. Increasing calcium alone appears to be pointless. There are in fact 22 nutrients associated with the maintenance of optimal bone health. All must be in the correct balance for the benefit to be seen.
When it comes to exercise it is the load bearing, bone stressing forms that boost strength. Keep those fit astronauts in mind. Take away gravity and you take away the stimulus for bone health. If you don’t feel that your joints are up to a pounding work out there are other options. Consider balance exercises that strengthen your legs and challenge your balance, such as Tai Chi, can decrease your risk of falls. There are also posture exercises that can improve your posture and reduce rounded or “sloping” shoulders can help you decrease the risk of fractures, especially in the spine. Finally there are a range of functional exercises designed to improve how well you move can help you in everyday activities and decrease your risk of falls and fractures. For example, if you have trouble getting up from a chair or climbing stairs, you should do these activities as exercises, simply try standing up and sitting down several times until you are tired – it’s a start! There is a growing interest in both Yoga and Pilates. Both these methods can also improve strength, balance and flexibility; however people with low bone density or osteoporosis should avoid certain positions to prevent fractures.
All in all, there is a lot you can do to protect and build your bone health.
• Eat well and choose from a variety of foods.
• Move towards a more vegetarian style of eating and rely less on meats for protein.
• Stop smoking and curb any regular excessive alcohol intake.
• Start an exercise plan aimed at loading bones or improving posture and balance.
• Take extra vitamin D3 along with a good all-round bone nutrient such as OsteoPrime or Osteo Factors.
• If you think your bones may be at risk get a heel scan or bone density scan to be on the safe side.
Further Reading: Preventing and Reversing Osteoporosis by Dr Alan Gaby MD.