This article was written by Associate Registered Nutritionist (ANutr) Sophie Gastman, and reviewed by Registered Dietitian Maeve Hanan.
The impact on bone health is an often overlooked consequence of disordered eating. Unlike some of the other physical side effects such as hair loss, fatigue and loss of period, deteriorating bone health is one that can be less obvious to spot.
This article will break down why bone health is so important, how disordered eating can impact this and practical tips to manage bone health in recovery.
Understanding Bone Health
Our bones have two main functions – they give our body structure, allowing us to move and stay upright, and they also act as a storehouse for essential minerals, such as calcium and phosphorous.
We all have a maximum strength and density our bones can reach. This is called peak bone mass, and is largely determined by our genetics. However, lifestyle factors, such as diet and exercise, will influence whether or not we reach our full bone mass potential.
An essential point to highlight is that the majority of bone mass is achieved during childhood and adolescence.
The window most people will reach their peak bone mass is between the ages of 25 and 30.
After this, your bone mass gradually starts to decrease over the years. This is why it’s so important to look after your bone health, as the closer you get to reaching your peak bone mass during that window in adolescence, the more bone you will have “in the bank” to see you through as you age and prevent the onset of osteoporosis.
Impact of Disordered Eating on Bone Health
The main cause of poor bone health in those with disordered eating is inadequate nutrition, however, this is not the sole cause. It is more the result of the complex interplay between multiple factors related to disordered eating.
Inadequate nutrition, when coupled with being underweight, elevated stress hormones and other hormonal imbalances, has a cascading effect on various aspects of health, including the menstrual cycle, which in turn directly influences bone health.
For example, if you are at a low body weight, less weight bears on your bone, which will eventually lead to bone loss as well as the loss of muscle which strengthens and supports your bones.
Hormonally, things can get more complicated.
Disordered eating behaviours can wreak havoc on hormones that play an important role in bone health. For example, low levels of estrogen are common in those with eating disorders, and estrogen is a key regulator of bone metabolism in both men and women, with lower levels being associated with decreased bone mineral density (1). These low levels of estrogen are a common cause of amenorrhea (absence of a menstrual period), which can also reduce peak bone mass and increase risk of osteoporosis (2).
Research has also shown that higher levels of the stress hormone, cortisol are associated with disordered eating patterns (independent of body mass index) (3), and cortisol is known to have a negative impact on bone mineral density (4). The impact is two-fold as prolonged excess levels of cortisol in the blood may not only decrease calcium absorption in the intestine but also decrease bone formation (5).
Another important hormone for bone health that is impacted by disordered eating is IGF-1 (6). This growth hormone is fundamental for both bone development during puberty and bone health throughout life (7).
It’s particularly important to emphasise that when disordered eating behaviours manifest during youth and adolescence, there’s a risk that bones may not develop to be as strong and dense as they should be. This is because it aligns with the critical period of when peak bone mass can be achieved, as discussed earlier in this article. The earlier disordered eating occurs, and the longer it persits, the greater the risk for bone loss and ultimately, developing osteoporosis (8).
Managing Bone Health in DE Recovery
The best way to support your bone health when recovering from disordered eating is by prioritising your nutrition.
Here are a few bone healthy nutrients to focus on:
Calcium is an essential component of our bones that keeps them strong, and adults need about 700mg a day. Good sources include milk and other dairy foods, green leafy vegetables, tofu, nuts, fortified plant-based milks, bread and any other fortified foods.
Vitamin D is needed in order to help our bodies absorb calcium and adults need 10 micrograms a day. Foods high in vitamin D include oily fish, like salmon and mackerel, egg yolks and fortified foods like cereals and bread, although it’s difficult to meet our daily requirement through food alone. Luckily, our bodies can make vitamin D through exposure to direct sunlight, but in the UK this only happens between March and September. During the winter months, it’s recommended to take a daily vitamin D supplement.
Alongside getting enough calcium and vitamin D, ensuring you get enough protein is also helpful for optimal bone health, particularly if you are still growing. Both animal and plant sources of protein will have a positive impact on your bone health.
Other Important Minerals
Magnesium and phosphorous also aid in the formation and maintenance of healthy bones. Good sources of these minerals include dark chocolate, nuts, seeds, dark leafy greens, avocados, dairy, red meat and poultry.
Vitamin K helps to make various proteins that are essential for producing healthy bone tissue. Good sources of Vitamin K are green leafy vegetables, like kale, swiss chard, spinach and broccoli.
If you are underweight, it’s important to prioritise weight restoration as research has shown that this is one of the most effective strategies to stop or reverse any bone loss (9).
Weight restoration will also help to resume the menstrual cycle, which will also have a positive impact on bone health by maintaining or increasing bone mineral density (10).
Being physically active is also a key factor in maintaining strong bones as the more you use them, the stronger they get. Both weight bearing exercising and muscle strengthening exercises are normally recommended to keep bones strong.
However, during recovery from disordered eating, a balanced and mindful approach to exercise is needed.
If you are underweight, have lost your menstrual cycle, or are engaging in excessive exercise, it may still be necessary to limit physical activity. In these cases, alongside considering adequate nutrition, rest and hormonal balance, incorporating low-intensity weight bearing activities like walking, stair climbing, or dancing may be recommended. Always follow the individual advice of your treatment team.
Overall, bone health is not something that should be overlooked or underestimated in the context of disordered eating as it can have a lasting impact. However, focusing on proper nutrition, weight restoration and mindful exercise can help to mitigate any adverse effects.
If you are struggling with disordered eating, you can find information about how we can support you here.
- Cauley, J.A. (2015) ‘Estrogen and Bone Health in men and women’, Steroids, 99, pp. 11–15. doi:10.1016/j.steroids.2014.12.010.
- Gordon, C.M. and Nelson, L.M. (2003) ‘Amenorrhea and Bone Health in adolescents and Young Women’, Current Opinion in Obstetrics and Gynecology, 15(5), pp. 377–384. doi:10.1097/00001703-200310000-00005.
- Lawson, E.A. et al. (2011) ‘Appetite-regulating hormones cortisol and peptide YY are associated with disordered eating psychopathology, independent of body mass index’, European Journal of Endocrinology, 164(2), pp. 253–261. doi:10.1530/eje-10-0523.
- Lawson, E.A. et al. (2009) ‘Hypercortisolemia is associated with severity of bone loss and depression in hypothalamic amenorrhea and anorexia nervosa’, Endocrinology, 150(11), pp. 5191–5192. doi:10.1210/endo.150.11.9998.
- Fazeli, P.K. and Klibanski, A. (2014) ‘Anorexia nervosa and Bone metabolism’, Bone, 66, pp. 39–45. doi:10.1016/j.bone.2014.05.014.
- Brambilla, F. et al. (2018) ‘Growth hormone and insulin-like growth factor 1 secretions in eating disorders: Correlations with psychopathological aspects of the disorders’, Psychiatry Research, 263, pp. 233–237. doi:10.1016/j.psychres.2017.07.049.
- Locatelli, V. and Bianchi, V.E. (2014) ‘Effect of GH/IGF-1 on bone metabolism and osteoporsosis’, International Journal of Endocrinology, 2014, pp. 1–25. doi:10.1155/2014/235060.
- Biller, B.M. et al. (1989) ‘Mechanisms of osteoporosis in adult and adolescent women with anorexia nervosa*’, The Journal of Clinical Endocrinology & Metabolism, 68(3), pp. 548–554. doi:10.1210/jcem-68-3-548.
- Steinman, J. and Shibli-Rahhal, A. (2019) ‘Anorexia nervosa and osteoporosis: Pathophysiology and treatment’, Journal of Bone Metabolism, 26(3), p. 133. doi:10.11005/jbm.2019.26.3.133.
- Indirli, R. et al. (2022) ‘Bone Health in functional hypothalamic amenorrhea: What the endocrinologist needs to know’, Frontiers in Endocrinology, 13. doi:10.3389/fendo.2022.946695.