Contributed by Abi Woodliffe-Thomas
Before we get into the science behind the nutritional benefits on bone health, it is important to understand what osteoporosis is and how it can develop. When linking to disordered eating patterns, low oestrogen levels are the main driver to significant losses in bone density, as well as the undernourishment of fuel that supports bone health. Individuals with disordered eating, specifically anorexia, often produce cortisol (stress hormone) in excess which triggering bone loss.
What is osteoporosis?
Osteoporosis is a disease that weakens bones to the point where they are at a heightened susceptibility to break, and more often than not, osteoporosis affects bones in the hip, spine and wrist.
While osteoporosis can be avoided, there are some important risk factors to be aware of for developing the degenerative bone condition (1):
Gender - Females are at an increased risk compared to males, and even more at risk if their mother or family member have had the condition
Poor lifestyle – Smoking, excessive caffeine and alcohol intake, with the absence of exercise can increase risk of osteoporosis
Poor nutrition – Linking to disordered eating habits, malnutrition can enhance the development of osteoporosis as the body hasn’t got enough nutrients in order to protect, build and strengthen bones
Amenorrhea (loss of menstrual cycle) – One of the biggest warning signs for disordered eating is also a red flag for osteoporosis, this is due to the reduction in oestrogen levels which effect calcium uptake and absorption in bones.
A lifelong lack of calcium is one of the leading causes of osteoporosis, contributing to a diminished bone density, early bone loss and an increased risk in fractures. Eating disorders also have a role to play in the disease onset, this is due to the severe restriction of nutrients, persistent impactful force through overtraining and being underweight weakening bones in both men and women (2).
I've also heard of osteopenia, what is it?
People often get confused between osteoporosis and osteopenia. Osteopenia is the stage before osteoporosis which is characterised by a lower than average bone density for your age, yet not low enough to be classified as osteoporosis.
The main difference between the two is the severity of bone loss. Although osteopenia is characterised by bone loss that is less severe than that of osteoporosis, the risk of fractures is still high in osteopenia compared to normal bone, yet lower than someone with osteoporosis
Is osteoporosis reversible?
You can reverse the consequence of osteoporosis; however, you cannot completely reverse the condition. There are varying degrees of the severity of osteoporosis and treatment, be it exercise, weight maintenance and/or nutrition can prevent the condition from worsening.
Can amenorrhea impact bone health?
Amenorrhea has a profound impact on a female’s bone density, specifically in adolescence and early 20's as this is a critical period for bone health. The amount of bone being laid down is enhanced by factors such as calcium intake, vitamin D and a balance of good nutrition and exercise. (3)
Amenorrhea is commonly exacerbated by overtraining and under-fueling which can lead to a decrease in body weight and essential hormones like oestrogen and progesterone. Oestrogen and progesterone are needed to lay down new bone so a reduction in these hormones means that bone is unable to be built up as it needs to.
The effects of nutrition on bone health
There are three key nutrients that are needed for good bone health:
Calcium is the most abundant mineral that makes up our bones, followed by magnesium. With 99% of calcium being in our bones and teeth, this mineral is essential (4) for bone and teeth health.
Calcium is found in most dairy products (cheese, yoghurt and milk) as well as spinach, kale, oily fish (with small bones) and fortified foods such as soy and cereals, making it an achievable mineral to consume even when following a dairy-free or vegan diet. We always encourage a food first approach with calcium, however if you are struggling to eat enough book in to see a registered dietitian or your GP to talk about supplementation options.
Our bodies use calcium continuously, so we must replace it regularly via our diet. The recommended daily allowance (RDA) for calcium is dependent on age and sex (5):
1000mg per day for adults, aged 19 to 50 years of age
1200mg per day for women aged over 50 years of age (due to the menopause)
1200mg per day for men once over 70 years of age
It is important to note that for individuals with an eating disorder and/or osteoporosis, calcium intake is higher than the RDA. Individuals should aim to consume 4 serves of dairy foods (or equivalent) a day.
Vitamin D works alongside calcium to promote good bone health. The two are actually a team, because vitamin D increases our absorption of calcium, which we know is integral for strong, healthy bones.
Vitamin D also improves the function of muscles, which can help your balance and decrease the likelihood of falling and suffering a bone fracture. It is advised that for those living in colder, less sunny climates supplement vitamin D between the months of October and April (6). You can