Body & Fitness

Unlock your family health tree

Some diseases and conditions are genetic, so asking your parents key health questions plays an important part in your own lifestyle planning, says Professor Kerryn Phelps.
Family tree

Many health conditions ‘run in families’, but you are not a powerless captive to your genes.

By knowing your inherited predisposition to preventable or manageable diseases, you can make changes that will mean you can avoid the impact of some of these conditions.

Has a family member had a blood test showing elevated iron levels?

An inherited condition called haemochromatosis causes the body to absorb more iron than normal from food. It is one of the most common inherited diseases. If you inherit the gene from one parent, you are a carrier and may pass it on to your children. To develop the disorder you have to inherit the gene from both parents. Excessive iron can cause damage to your liver (shown by an increase in liver enzymes), heart and pancreas (causing a form of diabetes), and joints.

Your action plan: If a member of your family has been diagnosed with haemochromatosis or found to have elevated iron levels or unexplained elevated liver enzymes on a blood test, ask your doctor for a blood test to check your iron levels. The gene test is available through your GP. If iron levels are elevated, it is treated by removing blood as often as needed to keep iron at normal levels. You will be advised not to take any supplements containing iron, reduce iron-rich foods, avoid vitamin C supplements (which increase iron absorption) and to keep alcohol to a minimum.

Has anyone in your family had bowel cancer or been diagnosed with polyps?

Family history is one of the risk factors for bowel cancer. A strong family history means one first degree relative diagnosed before the age of 45, or two first degree relatives diagnosed at any age. Bowel cancer is preventable with early detection of polyps on colonoscopy or investigation of gut symptoms or a positive faecal occult blood test (FOBT). Screening begins at 50.

Your action plan: Discuss your risk with your GP, who will determine the best screening method for you. According to Bowel Cancer Australia, changes in lifestyle could reduce the incidence of bowel cancer by up to 75 per cent. Increasing vegetables, fruits and other sources of fibre, maintaining calcium and vitamin D levels, regular physical activity, reducing red meat, avoiding processed meats, maintaining a healthy weight and avoiding alcohol are all ways you can help yourself.

Have any close relatives had breast cancer?

Five to 10 per cent of breast cancer cases are inherited and having a mother with breast cancer doubles your risk. Mutations in the BRCA1 and BRCA2 genes are inherited. One copy of the altered gene in each cell is sufficient to increase your chance of developing cancer. However, some families have a strong history of breast cancer without having these genes.

Your action plan: If you have a family history of breast cancer, ask your GP about screening and whether to refer you for genetic counselling. If you are found to be at higher risk, you will be recommended to have more frequent screening. Lifestyle factors can reduce your risk. Limit alcohol, avoid vitamin D deficiency, exercise regularly, don’t smoke, maintain a healthy weight, eat plenty of vegetables, fruit and wholegrains, limit menopausal hormone replacement and minimise unnecessary radiation exposure to your chest area. Women at very high risk may consider preventative mastectomy.

Angelina lost her mother Marcheline Bertrand to ovarian cancer in 2001.

Has one of your parents had a bone fracture from a seemingly minimal trauma?

Osteoporosis is a bone weakening disease. It tends to run in families, but a specific gene has not been identified. Also increasing the risk are premature menopause before 45, nutritional deficiency, overactive thyroid, undiagnosed coeliac disease, inflammatory bowel conditions, long-term use of steroid medicines, having a light frame and drinking more than four alcoholic drinks a day.

Your action plan: Talk to your GP about your risk and make a plan for testing your bone density. Lifestyle factors throughout life are extremely important. Eat calcium-rich foods, maintain adequate vitamin D levels, avoid smoking, limit alcohol and caffeine, and make sure you do regular weight-bearing and strength exercise.

Do members of your family have problems digesting gluten or been diagnosed with coeliac disease?

Coeliac disease is an inherited condition where the immune system reacts to gluten, a protein found in wheat, oats, rye and barley, which causes damage to the small bowel. Many people with coeliac disease are undiagnosed and continued exposure to gluten causes gut damage, skin problems, infertility, anaemia and a long-term increased risk of bowel cancer.

Your action plan: If you have coeliac disease, you need to adopt a strict gluten-free diet for life. Your GP can arrange for screening of you and your family members. If you have coeliac disease, I would advise you to see a dietitian for detailed instructions on a healthy, balanced gluten-free diet. Check for any nutritional deficiencies such as iron, vitamin B12, calcium and vitamin D, and supplement.

Your family tree

It is not always possible to know the details of your family health tree. In some cultures, family members are reluctant to talk about medical problems. If you are adopted, you may not have information about your biological parents. With open adoption, it may be easier to obtain that information. Your parents or grandparents may have died without letting you know the details of their health issues. Genetic testing is becoming increasingly available and this can overcome a lack of knowledge about your family’s medical history.

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