“Osteo” means bone, and “porosis” means porous… so when you have osteoporosis, your bones become thin and weak, and there’s a higher risk of breaking a bone especially if you fall.
Clinical definitions of osteoporosis are based on the measurement of bone mineral density (BMD) from a dual-energy X-ray absorptiometry (DXA) scan. Our bones are constantly being turned over and remodelled, with old bone broken down by osteoclast cells (bone resorption) and replaced by bone building osteoblast cells (bone formation). When bone resorption exceeds the rate of bone formation, bone loss occurs which can lead to osteoporosis.
Peak Bone Mass (PBM) is the highest level of bone mass that we as individuals can achieve, and we tend to reach PBM at around the age of 20, with about 26% of adult bone being accumulated during our pubertal spurt (girls 11-13 years, boys 13-15 years). To achieve their maximum PBM, it's essential to encourage our children and teenagers to drink plenty of milk in order to meet their calcium requirements... or to ensure that they have other sources of calcium in their diet.
This PBM plateaus and remains stable until around the age of 30 years, and then we’ll begin to experience some slight bone loss. When ladies reach menopause, and oestrogen levels fall dramatically, the rate of bone loss increases, but remember that men are not immune to osteoporosis either! Don't despair, if like me you're a little north of 20, we can make lifestyle and dietary choices to help maintain our bone health.
Osteoporosis Risk Factors
Women: Oestrogen deficiency caused by
- early menopause or hysterectomy (age <45 years)
- loss of periods (>6 months, excluding pregnancy) as a result of over-exercising or over-dieting
Men: Low levels of male hormone testosterone
Women and Men:
- Previous fragility fracture
- Close family history of osteoporosis
- Long term use of oral corticosteroids (for asthma or arthritis)
- Malabsorption problems (coeliac disease, Crohn's disease, gastric surgery)
- Low BMI <19kg/m2
- Long term immobility
- Heavy drinking
Nutritional Factors for Healthy Bones
Calcium: The richest sources of dietary calcium are found in milk and dairy products. A 200ml glass of cow’s milk or 150g yoghurt will provide ~250mg calcium.
Recommended Calcium Intake (ideally from diet)
11-18 years: Female: 800mg/day, Male: 1000mg/day
19-50 years: Female: 700mg/day, Male 700mg/day
Breastfeeding mums: 1250mg/day
Post menopausal women: 1200mg/day
Coeliac Disease: 1000-1500mg/day
Inflammatory Bowel Disease: Adults: 1000mg/day, Post menopausal women and men over 55 years: 1200mg/day
Vitamin D: Our richest source of vitamin D is from sunshine, but that disappears in the UK autumn and winter months, which is why we recommend taking a vitamin D supplement between October and March. It is difficult to meet vitamin D requirements through diet alone. See my blog: Vitamin D: the sunshine vitamin
Recommended Vitamin D Supplementation Intake during UK Autumn/Winter: Babies >1 year - adults: 10mcg/day
Alcohol: In large amounts, alcohol is toxic to osteoblasts, and reduces bone formation. More reason to stick within the recommended alcohol intakes of not more than 14 units per week, spread over 3 days or more and having at least 2 alcohol free days per week.
The risk of developing osteoporosis can be reduced by:
- Acquiring optimal peak bone mass
- Maintaining healthy bones throughout adulthood
- Reducing the rate of bone loss in later life
Please contact me via my website www.elaineallertondietitian.com if you have any concerns about your current diet. You’d keep a 3-day food/drink diary, which I’d analyse to give individualised dietary advice helping to prevent nutritional deficiencies, or reassurance that you’ve got a balanced diet that’s likely to be meeting all your nutritional requirements.