In a recent Instagram post, the actor Jameela Jamil revealed she has poor bone density, despite only being in her 30s. Jamil blamed this finding on 20 years of dieting – urging her followers to be aware of the harms diet culture can do to your health.
Author
Adam Taylor
Professor and Director of the Clinical Anatomy Learning Centre, Lancaster University
Bone density is important for many reasons, primarily because it acts as a reservoir for many of the important minerals our bones need to function well. Many factors can affect your bone density – and as Jamil has pointed out, diet is one component that has a significant effect on bone health.
Bone is a living tissue. This means our skeleton according to the stresses and strains it’s put under. Everything from fractures to exercise require our bones to change their shape or density. This is why a weightlifter’s skeleton is than a marathon runner’s.
The biggest skeletal changes we experience happen in our younger years. But bones keep changing throughout our lives depending on how active we are, what our diet consists of, and if we’ve suffered an injury or disease.
Bones are , such as collagen, as well as minerals – largely calcium. This is a for us, as it keeps our bones and teeth strong and helps repair and rebuild any injured bones.
But other minerals and vitamins are also important. For example, vitamin D supports calcium, playing a key role in . This is where calcium in our bones to create the mineral crystal . This crystal is crucial to our bone mineral density (also known as “bone mass”), as it helps bones remodel and maintain their structural strength.
– the type of scan Jamil referred to in her post – can measure the density of these crystals in bones. The detected, the healthier the bones are.
We hit peak bone mineral density in our , when our body has grown to full size and our metabolism is working its best. From here, it’s possible to maintain into your late 30s for women and early 40s for men, with the right diet and activity. But after this point, it begins to decline.
Bone density
We accrue calcium over many years. It initially comes from our mother, then later from our diet. Our body accrues calcium so it can adapt to times when calcium demand is greater than what we can get from our diet – such as during pregnancy, when the foetus needs calcium to .
However, relying solely on this skeletal calcium reserve can’t be sustained for lengthy or repeated periods, because of how long it takes to be replenished. This is why diet is so important for bone density – and why a poor diet can cause extreme damage, especially when certain food groups or minerals are consistently left out.
For instance, studies have shown consuming soft drinks, (), more than four times a week is linked with and increased fracture risk. This is true even after adjusting for many other variables that affect bone density.
These carbonated and energy drinks contain – often with none of the minerals, including calcium, that the body needs to function optimally. This causes the body to draw on its reserves if calcium isn’t being delivered elsewhere in the diet.
Diets high in added sugar can also have a detrimental affect on the skeleton. Excess sugar causes inflammation and other physiological changes, such as . Consuming high amounts of sugar is linked with , especially in children who substitute milk for sugary drinks. Excess sugar consumption also causes the body to , instead of reabsorbing it in the kidney as the body normally would.
have also been associated with increased risk of (a condition that weakens bones) in women – though larger studies are needed to better understand the effects of removing whole food groups on bone health.
also has a significant affect on – affecting a with the condition.
Low bone mineral density – especially in the spine – puts people with anorexia at because their bone thickness is reduced, increasing the likelihood of developing osteoporosis, which is associated with increased fractures.
Anorexia in young adulthood is particularly challenging. This is the stage where the skeleton is building itself to reach peak , so it’s depositing calcium at a record pace. When diet is insufficient and the body already starts drawing on its mineral reserves, there’s a potential that the bone density or calcium reserves in the body will never be optimal – increasing fracture risk for the .
Can bone health be fixed?
Optimal bone health starts in utero, but our prepubescent years are key to for later life. People who are behind the curve in early life may have difficulty achieving their peak, as poor bone mineral density can affect everything from our appetite to how efficient our gastrointestinal tract is at absorbing (including calcium). Supplements have a limited effect because our body can only absorb a set amount of any .
While it’s possible to in bone density that naturally happens as we age, some of the choices we make – such as not consuming enough calcium – can accelerate the decline. Biological sex also has a significant impact on our bone health in old age – with post-menopausal women at greater risk of osteoporosis because they , which helps keep the cells that in check.
Adam Taylor does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.
