Weight Loss and Bone Health: What You Should Know
Dr Charlotte Keigwin
Weight loss can transform health, improving blood sugar control, cardiovascular risk, joint health, and mobility. Whether achieved through changes in lifestyle, bariatric surgery, or medications such as Ozempic, Wegovy, or Mounjaro, reducing excess weight can be life-changing. Yet in the drive to reach a healthier weight, one important element is often overlooked: bone health.
Losing weight too quickly, or in large amounts, can reduce bone density, making bones thinner and more prone to fractures. This is not solely a concern for older adults. Bone loss can occur at any age during weight loss, particularly if the process is rapid or poorly supported. Hip and spine fractures can have significant, long-lasting consequences, even in otherwise healthy individuals.
However, weight loss and bone health do not need to be at odds. By understanding why bone loss can occur and taking practical, evidence-based measures, it is entirely possible to achieve a healthy weight while protecting skeletal integrity.
Why weight loss can affect bones
Bones are living, dynamic tissues that remodel continuously in response to forces placed upon them. When weight decreases, the mechanical load on bones reduces. With less load, bones receive fewer signals to maintain their density and strength, while bone resorption can increase, leading to a net reduction in bone mineral density, particularly in the hips and spine.
Rapid weight loss through severe calorie restriction, some medical treatments, or bariatric surgery can accelerate this process. Even moderate weight loss can result in measurable bone density reduction, which is why a thoughtful, well-supported approach is essential for long-term health.
GLP-1 medications and bone health
Medications such as semaglutide (Ozempic, Wegovy) and tirzepatide (Mounjaro) have changed the landscape of medical weight management. They work by mimicking hormones that reduce appetite and support blood sugar control, leading to effective and sustained weight loss for many individuals.
Understandably, patients often question whether these medications could affect bone health. Current evidence is reassuring. Research to date suggests that GLP-1 medications do not increase fracture risk and may, in some contexts, help preserve bone structure. Some studies indicate that these medications can promote bone formation and reduce bone breakdown.
However, it is important to remember that while these medications are effective tools for weight management, the weight loss they induce still reduces mechanical loading on bones. This is why a comprehensive, medically guided approach remains necessary to ensure that weight loss supports all aspects of health.
The importance of exercise
Regular exercise is one of the most effective measures for protecting bone health during weight loss. Weight-bearing and resistance exercises stimulate bones to maintain their density and strength.
Research shows that individuals who combine exercise with GLP-1 therapy maintain more bone density compared with those who use medication or diet alone. For example, studies have demonstrated that people who take a GLP-1 medication and follow a structured exercise programme can achieve the same, or greater, weight loss as those who take the medication alone, while preserving bone density in key areas such as the hips and spine.
Practical exercise options include walking, climbing stairs, dancing, and supervised strength training with weights, resistance bands, or body-weight exercises such as squats and lunges. Ideally, aim for at least two strength-focused sessions per week, combined with regular movement throughout the day. Supervised guidance can be invaluable for building confidence and establishing safe, effective techniques.
Nutrition: supporting bones during weight loss
Nutrition is another pillar of bone health. Calcium, vitamin D, and protein are particularly important during weight loss.
Calcium is essential for bone structure. Adults typically need 1000 to 1200 milligrams per day, best sourced from a varied diet including dairy products, fortified plant-based alternatives, leafy greens, and nuts.
Vitamin D supports calcium absorption and bone health. In the UK, many individuals require supplementation, particularly during winter months, with usual doses around 800 to 1000 IU daily depending on individual needs.
Protein is critical for maintaining muscle mass and bone matrix during weight loss. Including protein with each meal from sources such as fish, lean meats, eggs, legumes, dairy, and soy can help preserve lean tissue and support metabolism during a calorie deficit.
Avoid restrictive diets that exclude entire food groups without medical guidance, as these can inadvertently create nutritional deficiencies that undermine bone health.
Gradual weight loss protects bones
While rapid weight loss can be tempting, it often leads to a greater proportion of bone loss. Aiming for slow, steady weight reduction, typically around half a kilogram per week, allows the body to adjust while preserving lean mass and bone integrity. This approach also supports skin, mood, and metabolic health.
The same principle applies when using GLP-1 medications. These medications are effective in reducing appetite, but without adequate nutritional support and exercise, rapid weight loss can result in unnecessary bone and muscle loss.
Menopause, perimenopause and bone health
For women in midlife, maintaining bone health is especially important. Oestrogen plays a key role in reducing bone resorption, and as levels decline, bone turnover increases, raising the risk of osteoporosis.
Weight loss during perimenopause or post-menopause can add to this risk if not carefully managed. Including adequate calcium, vitamin D, and protein in the diet, alongside regular resistance and weight-bearing exercise, becomes even more important.
Women considering weight loss in midlife should ensure that their plan supports both metabolic and skeletal health, ideally under medical guidance.
Bariatric surgery and bone health
Bariatric surgery can be a life-changing intervention for those with severe obesity but carries specific considerations for bone health. Procedures that alter the digestive tract can affect nutrient absorption, particularly of calcium and vitamin D, increasing the risk of osteoporosis if not managed correctly.
Those planning or recovering from bariatric surgery should work with their medical team to monitor bone health, maintain appropriate supplementation, and engage in safe, regular exercise.
GLP-1 prescribing should be part of whole-person care
GLP-1 medications are powerful tools for weight management, but they are not a standalone solution. They alter how the body regulates appetite, energy use and metabolism. Yet health is interconnected, and altering metabolism in one area can have unintended effects in another.
Weight loss should not come at the cost of bone density, muscle mass, or nutritional adequacy. Using GLP-1 medications within a structured, medically guided programme ensures that the benefits of weight loss are achieved safely while protecting other aspects of health. It also allows for personal factors such as menopause, previous fractures, or other medical conditions to be considered carefully.
At Self London, GLP-1 prescribing is led by an expert with decades of experience in medicine ensuring that each prescription is part of a comprehensive health plan. Weight management is viewed within the context of overall wellbeing, with attention to nutrition, movement, and individual risk factors, ensuring that interventions support long-term health rather than focusing solely on weight alone.
Frequently asked questions
 Can you reverse bone loss during weight loss?
Bone density naturally declines with age, and weight loss can add to this process. However, the progression can often be slowed or stabilised through strength training, weight-bearing exercise, sufficient protein intake, and maintaining key nutrients.
Is taking calcium and vitamin D enough to protect bones?
Supplements are helpful but not sufficient on their own. Movement, muscle strength, and overall nutrition are essential to maintaining bone health during weight loss.
What is the best exercise for bone health?
A combination of resistance training to strengthen muscle and bone, along with weight-bearing cardiovascular activity such as brisk walking, dancing, or stair climbing, is most effective. Higher-impact activities may also be beneficial depending on individual health status.
How do I know if I am losing bone density?
Bone loss is silent and does not produce symptoms until a fracture occurs. A DEXA scan can assess bone density and may be recommended if you have risk factors such as menopause, a family history of osteoporosis, previous fractures, or significant weight loss.
A holistic approach at Self London
At Self London, we believe weight management should be part of a broader conversation about long-term health. Supporting bone integrity, muscle preservation, and metabolic health during weight loss reflects our commitment to whole-person care. Whether you are using GLP-1 medications, making lifestyle changes, or planning surgical weight loss interventions, our approach is designed to protect your health now and into the future.
Bones are living tissues that respond to how you move, fuel your body, and live each day. Taking care of your bones during your weight loss journey is not a restriction; it is an investment in your independence, resilience, and overall wellbeing.
Considering GLP-1 therapy?
If you are considering or currently using Ozempic, Wegovy, or Mounjaro as part of your weight loss plan, book a consultation at Self London. We will work with you to design a medically led, holistic approach that integrates medication, movement, and nutrition to help you achieve your goals while protecting your long-term health.
