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I am borderline osteoporosis

I am borderline osteoporosis. I have been eating all kinds of dairy products to increase my calcium levels but have read that it needs vitamin D to help the calcium stay in the body. I understand that cod liver oil is a good source of vitamin D but also that it may be bad for you so I'm confused. Should I just go back to sardines and other items or stay in the sun for a bit? Can you let me know about the safety of cod liver oil? Many thanks.

23 February 2021

Clinically, osteoporosis is a disease characterised by low bone mass and structural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. Osteoporosis itself is asymptomatic, and it often remains undiagnosed until a fragility fracture occurs.1 I am to believe you have had a discussion with GP to conclude that you are “borderline osteoporosis” because as mentioned above, there are no symptoms but there are a whole host of risk factors. 

In order to manage the progression of these risk factors to prevent clinically determined osteoporosis, your GP will/should have assessed you for vitamin D deficiency and inadequate calcium intake. People are at risk of vitamin D deficiency if they are aged over 65 years or are not exposed to much sunlight (because they are confined indoors for long periods or because they wear clothes that cover the whole body).

Furthermore, your calcium dietary intake may have been calculated. Should any deficiency have been detected, the next step would be to correct your vitamin D deficiency and ensure an adequate calcium intake. Your message eludes that you presented with no significant deficiency and that any corrections could be managed by your own dietary measures without the need for prescription. I can’t provide any specific quantities of vitamin D and calcium without knowing more about your case.

There are two sources of vitamin D in humans, a dietary form derived from plants and a form generated in the skin by the action of sunlight. The vitamin D from these sources then undergoes a series of reactions in the liver and then the kidney to produce an active form that the body can utilise. One use of this active vitamin D is to assist the absorption of calcium from the intestine and thus the restoration of bone formation.2 This explains the link between the two.

With regards to cod liver oil, as the name suggests, it is the type of fish oil obtained from the liver of cod. It is a rich source of vitamins A, D and omega-3 fatty acids. Vitamin A and D can be toxic in excessive amounts, however, the amount of these vitamins contained in supplements are unlikely to be harmful. There is also concern about the industrial contaminants in fish oil supplements – there is no immediate danger but risks come from long exposure to high levels.3

Based on your borderline diagnosis and the current absence of any particular quantities of vitamin D and/or calcium recommended to you by your doctor, it may be worth discussing your risk factors with your local pharmacist or GP again so you can tailor a vitamin D and/or calcium supplement to your exact requirements. I would also recommend taking a look at our article on osteoporosis and bone health for more ways to boost your bone strength.

You may find the following resources useful for information and additional support:

The National Osteoporosis Society provides support and information to people affected by osteoporosis, and works to improve public understanding of osteoporosis.

Healthtalkonline has a large collection of videos and transcripts of people's experiences of health and illness, including osteoporosis. There are also short articles for people with osteoporosis and the general public.

NHS has a health encyclopaedia which has a printable article on osteoporosis

Answered by the Health at Hand team.


1 Osteoporosis - prevention of fragility fractures

2 Rang and Dale’s pharmacology, 6th edition, pages 465-68, 2007.

3 Dietary Supplements, 4th edition, P.Mason, pages 152,168, 2012


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