How to keep your bones strong during weight loss

Bone health rarely gets the same attention as weight or muscle, but it deserves it just as much, especially if you're going through a significant change in your body. Bones are living tissue that responds to what you eat and how you move, and small, consistent habits make a real difference over time.

As a chef, nutrition coach and personal trainer, I look at bone health from both sides: what's on your plate and how you're using your body day-to-day. Neither one works particularly well without the other.

Why bone health matters during weight loss

Bone is constantly being broken down and rebuilt throughout life. During weight loss, particularly rapid or significant weight loss, that balance can tip toward more breakdown than rebuilding, especially if protein, calcium and vitamin D intake fall alongside your calorie intake. This is one of the reasons weight loss and bone health are often discussed together, alongside the more commonly known link with muscle loss. However, bone responds well to the right kind of exercise and nutrition, at any age. It's never too late to start supporting it properly.

Get enough calcium

Calcium is the mineral your bones rely on most for strength and structure. UK guidance recommends adults aim for around 700mg of calcium a day, and it's possible to hit that through food rather than relying on supplements alone.

Good sources include:

• dairy products (milk, yoghurt, cheese)
• tinned fish with bones, such as sardines or pilchards
• tofu
• leafy green vegetables like kale and broccoli
• fortified plant milks
• almonds

A simple way to build this in can look like this: a yoghurt at breakfast, a handful of almonds as a snack, and a piece of fish with bones once or twice a week. Adding these to their daily diets can get most people close to target without any real effort.

Don't overlook vitamin D

Vitamin D helps your body absorb and use the calcium you're eating, so getting enough calcium without enough vitamin D is a bit like buying the ingredients and never turning the oven on. In the UK, sunlight alone often isn't reliable enough to maintain good vitamin D levels, particularly between October and March, so a daily supplement of 10 micrograms is worth considering for most adults, especially if you spend a lot of time indoors or cover your skin outdoors.

Food sources are more limited but still useful:

• oily fish
• eggs
• fortified cereals
• spreads

Prioritise protein

Protein isn't just for muscle. It's part of the structure of bone itself, and studies have shown that adequate protein intake is linked to better bone density. If you're eating less overall during weight loss, protein is one of the last things you want to cut back on.

Move in ways that actually build bone

This is where things get specific, and where my personal training background comes in. Not all exercise affects bone in the same way. Bones respond best to two types of movement: weight-bearing exercise, where your body works against gravity, and resistance exercise, where your muscles work against a load.

Body weight exercise (aim for most days):

• brisk walking
• stair climbing
• hiking
• low-impact aerobics
• hopping on one leg (remember to change legs!)
• jumping on the spot

If you're not currently very active or have any concerns about your bones, start with walking and stair climbing, then build from there.

Other exercises (aim for at least two sessions a week):

A simple home routine, using just your bodyweight or light resistance bands to start:

• Squats: 2–3 sets of 10–12. Builds strength through the hips and thighs, two of the most common fracture sites.
• Step-ups (onto a low step): 2–3 sets of 10 per leg. A good bridge between weight-bearing and resistance work.
• Wall or knee push-ups: 2–3 sets of 8–10. Supports the wrists and upper body, another common area for fractures.
• Resistance band rows: 2–3 sets of 12. Strengthens the upper back, which also helps posture.
• Heel raises (calf raises): 2–3 sets of 15. Simple but effective for lower leg and ankle bone strength.
• Farmer's carries: hold a weight, or shopping bags, in each hand and walk back and forth for 20–30 seconds each way – a genuinely underrated one for full-body bone loading.

2-3 sessions a week, done consistently, will do far more for your bones than one intense session followed by weeks of nothing.

A few safety notes

If you have osteoporosis, low bone density, or any existing joint or bone concerns, it's worth speaking to a physiotherapist, exercise specialist or your GP before starting a new exercise routine, so it can be tailored to you. Swimming and cycling are excellent for general fitness and joint health, but because your body weight is supported by water or the bike, they don't load your bones in the same way and shouldn't be relied on alone for bone strength.

When to seek advice

Speak to your GP if you have a family history of osteoporosis, have broken a bone from a minor fall or knock, have gone through early menopause, or are concerned about your bone health for any other reason. Bone density can be assessed through your GP if needed, and there's no downside to checking early.

The takeaway

Strong bones come from the same everyday habits as everything else in this journey: enough protein, enough calcium and vitamin D, and regular movement that actually challenges your body. None of it needs to be complicated, and you don't need a gym to do most of it.

About Lisa Marley

Lisa is a RSPH-accredited Chef and Wellness Expert with an AfN Certified Diploma in Nutrition Coaching. Working alongside myBMI, she helps translate nutrition science into practical, everyday advice, creating recipes, meal ideas and healthy eating guidance that support sustainable weight loss and long-term wellbeing.

Find out more about her work here.

Sources:

• Bone health and falls. (2026) NHS Inform [Accessed 1 September 2026]
• Vitamin D. (2023) NHS [Accessed 1 September 2026]
• Bone health: Tips to keep your bones healthy. (2025) Mayo Clinic [Accessed 1 September 2026]
• Fracture prevention and osteoporosis. (date unknown) NHS [Accessed 1 September 2026]