What is cholesterol?

Cholesterol is a fatty substance found in our blood. It's essential and has many good uses – it's needed to make hormones and vitamin D in the body. But we only need a small amount. Too much cholesterol in the blood can increase the risk of heart disease.

We measure cholesterol through a blood test. The average level of total blood cholesterol in New Zealand adults is about 5.7 mmol/L4, which is one of the highest levels in the world5. 17% of all deaths in New Zealand can be directly related to high cholesterol6 and most of us would benefit from lower cholesterol levels.

Why is our cholesterol high?

A major contributor to high cholesterol in New Zealand is a poor diet. Saturated fats are known to raise blood cholesterol levels and many foods, such as fatty meats, full fat dairy products, coconut cream, biscuits, cakes, pastries, fried takeaways and some snack foods are high in saturated fats. However, there are many tasty foods that have no effect on blood cholesterol and some that actually lower blood cholesterol. To find out more about these foods, download the 'Heart to Heart' booklet: A simple guide to lower cholesterol through diet and lifestyle.

The Good and the Bad

Cholesterol in the blood comes in two main forms – which are often called 'good' and 'bad' cholesterol.

Good HDL cholesterol clears the blood of cholesterol, helping to reduce the risk of heart disease.
Bad LDL cholesterol can build up the arteries, increasing the risk of heart disease.

People with high cholesterol usually have high levels of 'bad' LDL cholesterol in their blood.

Simple cholesterol tests estimate your 'total' cholesterol whereas more complete tests provide additional information about total, LDL and HDL cholesterol. Your doctor can organise these tests, check for other risk factors and give you detailed advice. A registered Dietitian can provide you with tailored dietary advice to improve and manage your cholesterol and SPARC can help you find activities that suit you.

4 Ministry of Health and the University of Auckland. 2003. Nutrition and the Burden of Disease: New Zealand 1997-2011 Wellington: Ministry of Health (www.moh.govt.nz).

5 Russell DG, Parnell WR and Wilson NC. New Zealand people: Key results of the 1997 National Nutrition Survey. 1999. Ministry of Health, Wellington.

6 J Mackay, G Mensah, Atlas of Heart Disease and Stroke. World Health Organization. Geneva, 2004.