Osteoporosis, or thinning bones, is a silent health condition that can result in tremendous pain with fractures.

Osteoporosis usually occurs in older women (over 55 years old), but younger women and men may also be affected. Because the population of Singapore is aging rapidly, osteoporosis is likely to become an increasingly important health problem.

Dr Manju Chandran, Senior Consultant from the Department of Endocrinology at Singapore General Hospital and Dr Peter Moey, Associate Consultant at SingHealth Polyclinics, give detailed answers to your questions.

Question by vericheem

Why do women generally become shorter when they reach old age? Is this a symptom of osteoporosis? Will the higher consumption of high calcium food like milk and cheese slow down osteoporosis? Is calcium supplement helpful in slowing osteoporosis?

Thank you.
Mr Tang SY

Answered by Dr Manju Chandran Consultant/ Director Osteoporosis & Bone Metabolism Unit Department of Endocrinology Singapore General Hospital

It is not just women but men also become shorter with aging as part of the normal aging process. However if there is more than a 4 centimetre height loss when compared to peak adult height, then one should be concerned that there could be an underlying cause like collapse of a vertebra.

A balanced diet is important for bone development and maintenance as well as for general health. Evidence has established the role of adequate calcium intake in bone health primarily in the development of peak bone mass and in preventing bone loss.

An elemental Calcium intake of atleast 700 mg/day is recommended in adults above the age of 19 years. Higher intakes of 800-1000 mg is recommended in younger individuals.

Dietary sources of calcium are recommended as the primary source of calcium because of the other essential nutrients that are also found in high-calcium foods.

Calcium supplements and calcium fortified foods are additional sources of calcium for people unable to consume sufficient dietary calcium.

Question by healthblur

How do I know if I am risk of osteoporosis? Is there any definitive check that can tell me what is my current risk rate?

I read somewhere that a person's bone mass is highest at age 20-35 years. If I am now almost 50 years, does that mean its too late to do anything about it?

What should I do besides drink more milk and soyabean?

Why does weight-bearing exercise help? How much does it help?


Answered by Dr Manju Chandran Consultant/ Director Osteoporosis & Bone Metabolism Unit Department of Endocrinology Singapore General Hospital

There are certain factors that are associated with an increased risk of developing osteoporosis. They include what are considered non modifiable like

  • Age
  • Race (Being Caucasian or Asian)
  • Female gender
  • Early menopause
  • Low body weight
  • Positive family history especially maternal and modifiable risk factors such as
  • Low Calcium intake
  • Low Vitamin D intake
  • Estrogen deficiency
  • Sedentary Lifestyle
  • Cigarette smoking
  • Alcohol excess ( > 2 drinks a day)
  • Medications (steroid medications, if the dose of thyroxine used in the treatment of an underactive thyroid gland is too much etc )

A simple test that has been developed that can help a post menopausal Asian woman to assess her risk for developing osteoporosis and whether she should get a bone density test is called the OSTA (Osteoporosis Self Assessment Tool for Asians).

This is a simple calculation based on ones’s age and weight. When weight in kilograms is subtracted from age and is > 20, the risk for developing osteoporosis is high and the person should get a bone mineral density test done.

If it is between 0-20, then the risk is moderate and then if the person has had a low trauma fracture in the past or if any of the risk factors ( those listed above) are present then the person should get a bone mineral density test done.

If the OSTA score is less than 20, then the bone mineral density test can be deferred unless the person happens to have the risk factors listed above or has had a previous fragility fracture ( fracture induced by minimal trauma).

If you are a man over the age of 50, instead of the OSTA, the HPB in conjunction with the Osteoporosis Society of Singapore recommends using the 1 minute self evaluation test to estimate the risk of developing osteoporosis.

  1. Are you aged 65 and above? - Yes /No
  2. Do you have a family history of hip fractures? - Yes /No
  3. Do you have a thin or small body frame? - Yes /No
  4. Have you broken a bone after a fall? - Yes /No
  5. Do you smoke? - Yes /No
  6. o you consume less than the recommended level of calcium (800mg)? - Yes /No
  7. Do you engage in less than 30 minutes of physical activity daily? (e.g. jogging, brisk walking, dancing, stair-climbing)? - Yes /No
  8. Do you drink more than 2-3 standard drinks of alcohol a day? - Yes /No
  9. Have you taken steroid medication for more than 3 months? - Yes /No
  10. Has your doctor ever told you that your level of sex hormones (testosterone) is low? - Yes /No

It is never too late to take steps to strengthen your bones. A healthy balanced diet that is rich in Calcium and getting enough Vitamin D through adequate sun exposure along with weight bearing exercise will go a long way to help preserve bone mass.

Weight bearing exercise puts the weight of the body on the bone cells and stimulates it to grow. This benefit is manifest throughout one’s life.

Question by Dr. Aziz

Dear Dr. Chandran

I am keen to know treatment modalities available for osteoporosis.My mother 67 yrs had osteoporosis & bil knee OA for 20 yrs plus.She recently had bil knee replacement in Nov 2010.she is on biphosphonates for many years recently tried 2 to 3 types but still had sever gastritis the commonest side effect of biphosphonates,

I know they are beneficial but are it for her whole life & continuous .Is there any role of BMD like if it is in the normal range us can stop biphosphonates & later restart after sometime.

I am interested for Zoledronate due to its once a yr dose & safer drug as well.I need your personal experience about this drug.

Lastly I want to know your drug of choice for osteoporotic patients with severe gastritis unable to take usual biphosphonates.

Answered by Dr Manju Chandran Consultant/ Director Osteoporosis & Bone Metabolism Unit Department of Endocrinology Singapore General Hospital

I would recommend that your mother see a specialist for her condition. Each patient has individual needs and treatment will differ depending on the condition. If she is doing well after a few years, her bone mineral density has improved and she has not had any fractures, the doctor may decide to give her a “medication holiday”—but this has to be decided after a detailed evaluation.

I am interested for Zoledronate due to its once a yr dose & safer drug as well.I need your personal experience about this drug.

Zoledronic Acid is a once a year intravenous infusion given for the treatment of osteoporosis. A decision to give Zoledronic acid is something that has to be made after a detailed consultation with the specialist. It has to be made sure that the patient’s kidneys are working reasonably well before the patient is given the Zoledronic acid. It also has to be made sure that the patient is also adequately replaced with Vitamin D before the infusion.

Lastly I want to know your drug of choice for osteoporotic patients with severe gastritis unable to take usual biphosphonates.

A: There are several options for treatment of osteoporosis in patients who are unable to take oral bisphosphonates due to gastritis. These options include medications like Raloxifene, Strontium Ranelate, Intravenous Zoledronic Acid and Subcutaneos Teriparatide. The decision as to which medication is chosen has to be made after consultation with the specialist.

Question by chew_sally_maria

I'm 62 and on Rabeprazole for acid reflux.Due to my osteoporosis I was on Protos but had to discontinue because it worsen my acid reflux. I switch to Evista but found that it also had the same effect as Protos. Do Protos and Evista cause my acid reflux to worsen?

Answered by Dr Manju Chandran Consultant/ Director Osteoporosis & Bone Metabolism Unit Department of Endocrinology Singapore General Hospital

Any medication may be associated with side effects. Protos may very rarely cause nausea and diarrhea. Evista may rarely be associated with stomach pain. Worsening of acid reflux is not usually associated with either medication but nobody can conclusively say that it couldn’t happen.

Question by rachel

I am a woman in my early 40s. I just don't like to drink much milk, so only take maybe 1 or 2 glasses per week, and don't take much cheese either as I am worried it is fattening. Although the rest of my diet is pretty healthy, and I eat vegetables like spinach and brocolli, kai lan, etc at each meal, do I need to take a calcium supplement for my bones?

If so, what kind and how much should I take?

Are there any side effect I should worry about with supplements? Some friends told me that taking tablet supplements could contribute to stones in the gall bladder.

Whilst gel type supplements could create a lining in the stomach. Is this true?

I am worried to inaction.... Pls help!

Answered by Dr Peter Moey Family Physician Pasir Ris Polyclinic SingHealth Polyclinics

The daily recommended dietary allowances for Calcium by Health Promotion Board can be found here. At early 40s, you should have 800mg of calcium a day.

Spinach (cooked) contains 145mg of calcium per ¾ cup (100g).

Broccoli (cooked) contains 45mg of calcium per ¾ cup (100g).

Kai Lan (cooked) contains 160mg of calcium per ¾ cup (100g).

Depending on the amount you eat, you may need supplements.

Milk is high in calcium, the amount depending on the type and quantity you consume. High calcium milk powder (skim/non-fat) contains 450mg of calcium in 4 scoops (25mg). Low fat milk contains 300mg of calcium per glass (250mls).

If you do not like milk, soya bean is an alternative.

Soya bean (cooked) contains 300mg of calcium per cup (180g).

Soya bean drink (fortified) contains 200mg of calcium per glass (250mls). On the other hand, soya bean drink that is not fortified (such as those in hawker centres) contains around 40mg of calcium per glass (250mls). However, soya bean curd (tau huay) contains 190mg of calcium per bowl (270mg).

Fish is also a good source of calcium. Ikan bilis (dried with bones) contains 240mg of calcium in 2 teaspoons (40g). Sardines (with bones) contain 190mg of calcium per fish (50g).

So, with such a wide variety of food that contains calcium, you may not need supplements. Take a quick count... you may have already reached your calcium requirements without you even knowing. If you have not, it is definitely more interesting to hunt for your favourite food in Singapore than shop for calcium pills. 

Supplement for Osteoporosis

But if you really prefer supplements, calcium supplements come in various forms such as pills, capsules, liquid filled soft gelatin capsules, effervescence and chewy gums/sweets. The supplement differ mainly only in their actual amount of calcium, called elemental calcium. You can use the amount in each form to estimate how much you need to top-up from your diet (eg if you are short of 250mg, 1 tablet with 250mg elemental calcium is sufficient).

Calcium carbonate and citrate are common supplements as they contain more elemental calcium per tablet and are less expensive per unit weight of calcium. Calcium carbonate is cheapest but needs to be taken with food for the acid in the stomach to dissolve it. Calcium citrate has less elemental calcium but is more easily absorbed. Check with your pharmacist about the various brands of calcium supplements available.

Vitamin D is usually included with calcium supplements as it is essential for calcium absorption. It can also be obtained from diet or sun exposure. Dietary sources include cod liver oil, fatty or oily fish (such as salmon, cod and mackerel), eggs, liver and fortified foods such as milk, soymilk, margarine and cereal.

Taking excessive calcium may lead to kidney stones but is not a risk factor for gallstone development. So do not chomp non-stop on those chewy calcium supplement sweets!

Question by Jojo

Is Osteoporosis hereditary? My mum just diagnosed with osteoporosis and I am worried that I might at risk too.

Answered by Dr Peter Moey Family Physician Pasir Ris Polyclinic SingHealth Polyclinics

Osteoporosis is multi-factorial. History of fracture in a first degree relative (especially maternal) is a risk factor. While genetics play a role in osteoporosis, other factors may contribute to it.

Non-modifiable risk factors include low body weight, elderly age, height loss of more than 2cm over 3 years and personal history of previous fracture (as an adult). Potential modifiable risk factors for osteoporosis include cigarette smoking, alcohol abuse, lack of regular physical activity, prolonged immobilisation and low calcium intake (less than 500mg a day in Asians). So smokers, here is something to add to that list of heart attack, stroke, obstructive lung disease and cancers which your doctor has been telling you about.

Osteoporosis may also be a result of other diseases or medication intake (secondary osteoporosis). Medications such as prednisolone, anticonvulsants and excessive thyroxine may predispose to osteoporosis.

Ongoing disease conditions, e.g. hypogonadism, hyperthyroidism, hyperparathyroidism, Cushing’s syndrome, chronic obstructive airways disease, liver disease, malabsorption, chronic renal failure, rheumatoid arthritis, organ transplantation and anorexia nervosa are also causes. For ladies, menopause before 45 years old, either naturally or surgically (removal of ovaries during operation) is a risk factor for osteoporosis.

For ladies, the Osteoporosis Self-Assessment Tool for Asians (OSTA) can be used to assess your risk for osteoporosis. The simple way is to take your age (in years) minus your weight (in kg). If it is more than 20, your risk of osteoporosis is high and you should have a bone mineral density (BMD) measurement to confirm. If it is less than 0, your risk of osteoporosis is low and you can defer BMD measurement, unless you have high fracture risk. If it is between 0 and 20, your risk of osteoporosis is moderate and you should have your BMD measured if you have any risk factors or personal past history of fracture.

The main issue with osteoporosis is fracture and the associated complications. An easy way to evaluate your fracture risk is the World Health Organization (WHO) Fracture Risk Assessment (FRAX) Tool. It takes into consideration all the risk factors as mentioned above. At the time of this publication, FRAX is available for you to input your personal data to get an estimate of your 10 year fracture risk at “http://www.shef.ac.uk/FRAX/”. There is even an app version available for iPhone supported by the International Osteoporosis Foundation (IOF), called FRAX, by Doctor.

Ref: U11