I AM very worried about my friend. She has always been skinnier than me but still went on a diet in January. She is still convinced she needs to lose weight. How do I convince her she doesn't need to?

Whilst you do not say if your friend is dangerously thin, this is an area which needs careful handling as people who are overly concerned about their weight often do not accept there is an issue.

You could try talking to your friend about how they feel and encourage them to think about getting help from their GP if they want to lose weight in a healthy way. However, it is important you try not to put pressure on them or be critical of them as this could build resentment.

You can also offer to go with them to see their GP to talk about diet and nutrition. You can also consider support groups, which can provide information on helping a person you are worried about and the support you can provide to them or they can access themselves. A leading charity in this area is BEAT (Beating Eating Disorders), see their website at www.b-eat.co.uk for more information.

MY sister gave birth recently and needed a blood transfusion afterwards. Mum and baby are doing fine but I'd like to give blood and help someone else. The problem is I am really scared of needles. What can I do?

First of all, it is great your sister and her baby are doing well and fantastic you want to help by giving blood.

Donating blood often means saving a life and as you have unfortunately discovered, sometimes, even the procedures we take for granted today, such as childbirth, can give rise to complications where blood donations are needed.

The process itself takes around an hour and while a needle is involved, there is no need to actually look! The staff at any blood donation session will be used to this problem and know how to put you at ease. On arrival, you will be welcomed by a member of staff and asked to read some information and fill in a questionnaire about your health. As you are a new donor, a nurse will go through everything with you. Feel free to ask any further questions about the donation procedure.

You will then have a haemoglobin check or a test to make sure there is enough iron in your blood, this involves taking a pinprick of blood from your finger and is about as painful as a small scratch.

Assuming your iron levels are good and there are no other health issues, the donation process itself takes around 10 to 15 minutes and you will have someone with you throughout who will make sure you are comfortable and happy.

Finally, you'll be taken to rest, given a drink and a biscuit. Those receiving your donation, like your sister, will not know whom they need to thank but I can assure you they will be eternally grateful. You can find out where your nearest donation event is being held at the www.scotblood.co.uk website.

What is DVT?

DVT or Deep Vein Thrombosis is a blood clot in one of the deep veins in the body.

Blood clots that develop in a vein are also known as venous thrombosis.

DVT usually occurs in a deep leg vein, a larger vein that runs through the muscles of the calf and the thigh. It can cause pain and swelling in the leg and may lead to complications such as pulmonary embolism. This is when a piece of blood clot breaks off into the bloodstream and blocks one of the blood vessels in the lungs.

DVT and pulmonary embolism together are known as venous thromboembolism (VTE).

Symptoms

In some cases of DVT there may be no symptoms, but it is important to be aware of the signs and risk factors of thrombosis and see your GP as soon as possible if you think you may have a blood clot. DVT can cause pain, swelling and a heavy ache in your leg.

DVT usually (although not always) affects one leg. The pain may be made worse by bending your foot upward towards your knee.

Diagnosis

If you think that you may have deep vein thrombosis (DVT), see your GP as soon as possible.

Your GP will ask you about your medical history and your symptoms. However, it can be difficult to diagnose DVT from symptoms alone, so your GP may recommend a specialist test.

A specialised blood test, known as the D-dimer test, is used to detect pieces of blood clot that have been broken down and are loose in your bloodstream. The larger the number of fragments found, the more likely it is that you have a blood clot in your vein.

An ultrasound scan can also be used to detect clots in your veins. A special type of ultrasound, known as a Doppler ultrasound, can also be used to find out how fast the blood is flowing through a blood vessel. This helps doctors to identify when blood flow is slowed or blocked, which could be caused by a blood clot.

If the results of a D-dimer test and ultrasound scan cannot confirm a diagnosis of DVT, a venogram might be used.

A special dye is injected into a vein in your foot, which travels up the blood vessels of your leg. An X-ray is taken to see the dye. If there is a blood clot in your leg, the dye will not be able to flow round it and will show up as a gap in your blood vessel.

Treatment

DVT can be caused by long periods of inactivity or resting in one position. Like many health issues, prevention is better than cure. For example, If you are admitted to hospital, or are planning to go into hospital for surgery, your healthcare team will assess your risk of developing a blood clot while you are there.

If you are planning to have an operation and are taking the combined contraceptive pill or hormone replacement therapy (HRT), you will be advised to stop the drugs temporarily four weeks before you have your operation.

If you are at risk of getting a DVT, or have had a DVT previously, consult your GP before embarking on long-distance travel. If you are planning a long-distance plane, train or car journey (journeys of six hours or more), ensure you drink plenty of water, avoid excessive alcohol as this can lead to dehydration, avoid sleeping pills as they can cause immobility, and take occasional short walks when possible, even if it is only along the aisle of the plane or around the service station if you stop for fuel.

DVT is treated with anticoagulant medicines which prevent a blood clot from getting bigger. They can also help stop part of the blood clot from breaking off and becoming lodged in another part of your bloodstream (an embolism). Although they are often referred to as "blood-thinning" medicines, anticoagulants do not actually thin the blood. They alter chemicals within it, which prevents clots forming so easily.