High levels of 'good' cholesterol could mean a lower risk of bowel cancer, according to scientists.
A study claims increased levels of high-density lipoproteins (HDL) could make a difference to the way the body handles inflammation. High HDL levels 'collect' excess cholesterol in the blood and transport it to the liver where it is broken down.
Ways of boosting good cholesterol and reducing bad levels include quitting smoking, losing excess weight, taking frequent exercise and taking certain foods. The study said these include whole grains like oatmeal, oat bran and wholewheat products; nuts such as walnuts, almonds and brazil nuts; plant sterols and omega 3 fatty acids, such as those found in fish, flaxseeds and flaxseed oil.
In the latest study, published in the journal Gut, experts used data from more than 520,000 people taking part in the European Prospective Investigation into Cancer and Nutrition (EPIC), involving 10 countries.
Overall, more than 1,200 people developed bowel cancer during the course of the study. They were compared with more than 1,200 people without bowel cancer to check for differences between the groups.
Blood tests were taken to check for markers of cholesterol and people were asked about their diets and lifestyles. After adjusting for a wide range of factors, experts discovered that people with the highest levels of HDL cholesterol, and another blood fat called apolipoprotein A (a component of HDL cholesterol), had the lowest risk of developing bowel cancer.
Each rise of 16.6 milligrams per decilitre (mg/dl) in HDL and of 32 mg/dl in apoA reduced the risk of bowel cancer by 22% and 18% respectively.
The beneficial effect appeared to be confined to cancers of the colon rather than the rectum.