Blood tests of thousands of Canadians showed 41 per cent of adults had a high total cholesterol level, a new report says.

Statistics Canada released new data from its Canadian Health Measures Survey on Tuesday, based on samples that were taken from March 2007 to February 2009.

Blood samples from about 5,600 participants at 15 sites across the country showed about 27 per cent of people aged 20 to 39 had high levels of total cholesterol over the study period.

"This is not something that we see only as people are aging," said Jeanine Bustros of Statistics Canada's physical health measures division.

"It's quite a bit. So I think there's room to have better programs for prevention."

Unhealthy cholesterol levels can be controlled and even reversed through diet and lifestyle changes. If those changes aren't enough, doctors will prescribe statin medications — the best selling class of drugs in the world.

Among those aged 40 to 59 who were tested, 47 per cent had high levels of total cholesterol, which is a measure of all cholesterol and other types of fats in the blood. For those aged 60 to 79, 54 per cent did.

Unhealthy levels

The Heart and Stroke Foundation of Canada also says almost 40 per cent of Canadian adults are classified as having high blood cholesterol levels. Health Canada suggests the following total cholesterol levels less than 5.2 millimoles per litre (mmol/L) is ideal and more than 6.2 mmol/L is considered high.

About 36 per cent of adult Canadians had unhealthy levels of low density lipoprotein or LDL cholesterol, known as "bad cholesterol," that can lead to cardiovascular disease. Less than 3.5 mmol/L is considered ideal and more than 4.0 mmol/L is high, according to Health Canada.

High concentrations of LDL and lower concentrations of HDL are strongly associated with cardiovascular diseases, the leading cause of death in adult Canadian men and women.

Unhealthy levels of LDL cholesterol generally increase with age, but peaked at 43 per cent among adults aged 40 to 59 in the new study.

About 30 per cent had too little high density lipoprotein or HDL cholesterol, known as "good cholesterol" that helps to prevent atherosclerosis or hardening of arteries by taking LDL out of the blood. More than 0.9 mmol/L is desirable.

About 36 per cent of Canadians aged 20 to 79 who did not have a healthy level of good cholesterol were obese, compared with 16 per cent of those with a healthy level of good cholesterol.