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Welcome to the Health Defence Blog - a blog about health, wellness and a healthier you. Brought to you by the Health Defence team at Chest Heart & Stroke Scotland, you'll find up-to-date information on a range of topics from what's in your food to the latest advice on e-cigarettes!

CHSS Advice Line nurse Laura Hastings, July 2013.

Guest blogger: Laura Hastings, CHSS Lead Advice Line Nurse

January 26, 2018

More than half of adults in Scotland have high cholesterol, which increases the risk of developing serious health conditions including heart disease and stroke. 

This is because cholesterol build-up narrows your arteries, reducing blood flow to your heart and brain, and increasing the risk of a blood clot developing.  Yet you will usually not know if you have high cholesterol unless you have a simple blood test for your GP or practice nurse.

What is cholesterol?

Cholesterol is a waxy, fatty substance found in all of your body’s cells.  It is needed to help make hormones and vitamin D, as well as in the process of digestion. Your liver makes all the cholesterol you need. However, some foods also contain additional cholesterol.

There are two types of cholesterol:

LDL (low-density lipoprotein):  builds up fatty patches in the artery walls (called atheroma), causing hardening or “furring up” of the arteries (like limescale furring up a water pipe).  This is the “bad” cholesterol which increases your risk of heart disease and stroke.

HDL (high-density lipoprotein): carries cholesterol away from your cells and back to your liver to be processed and excreted.  This is the “good” cholesterol so higher levels of this are beneficial.

In the diagram below, you can see how the build-up of atheroma narrows the blood vessels and reduces the flow of blood. Sometimes a blood clot forms at a patch of atheroma and the blood vessel becomes completely blocked. Depending on the blood vessel involved, this can cause a heart attack or stroke.

High cholesterol levels increase your risk of atheroma forming in your blood vessels

What can cause high cholesterol?

  • Being overweight
  • Unhealthy diet – high levels of saturated fat (e.g. in cakes and biscuits)
  • Smoking – causes narrowing and stickiness in your arteries (atherosclerosis)
  • Diabetes 
  • High blood pressure
  • Family history of stroke or heart disease
  • Inherited condition causing high cholesterol (familial hypercholesterolaemia)

What should my cholesterol levels be?

 Total cholesterol:

  • 5mmol/L or less for healthy adults
  • 4mmol/L or less if you have diabetes or other risk factors for heart disease and stroke

 LDL (“bad”) cholesterol:

  • 3mmol/L or less for healthy adults
  • 2mmol/L or less for those at high risk

HDL (“good”) cholesterol:

  • above 1mmol/L for men and above 1.2mmol/L for women

 How do I help keep my cholesterol at a healthy level?

  • You may need to reduce your weight or waist measurement. People who lose 5-10% body weight have significant reductions in LDL cholesterol.
  • Eat a healthy diet – cut down on saturated fat (e.g. fatty meats, cakes and biscuits). Include more high fibre foods, plenty of fruit and vegetables, pulses, lentils, oats and oily fish (e.g. salmon or sardines). 
  • Get more active – regular exercise helps to increase your HDL and move more LDL to your liver to be expelled. Walking more is a great way to start!
  • If you smoke, ask your GP or pharmacist for advice and local support available to quit.

If despite your best efforts your cholesterol remains high, your GP may prescribe a statin (a cholesterol-lowering medication) to help reduce your risk of heart disease and stroke.

Further information

To find out more about cholesterol, read the CHSS ‘Cholesterol’ factsheet, or contact the CHSS Advice Line nurses on: Freephone 0808 801 0899, or email 

***Disclaimer: always seek medical advice before starting a new diet, exercise regime or medication. The information in these articles is not a substitute for professional advice from a GP, registered dietitian or other health practitioner.

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