TORONTO -- Blood pressure machines for home use are not always accurate and may give falsely high or low readings that could affect how people look after their health, says Hypertension Canada, which has released its first list of recommended devices, along with tips on the proper way to use them.

The list of validated devices can be found on the organization's website.

More than 15 million Canadians are living with or at risk for hypertension, and regular monitoring can indicate whether lifestyle changes or medications are working to keep blood pressure within a healthy range.

For most of the population, the ideal blood pressure is 120/80 mmHg or lower. Left untreated, chronically high blood pressure, or hypertension, can lead to heart disease, stroke, kidney failure and dementia.

"Hypertension is highly sensitive to treatment, so accurate monitoring of blood pressure control is of key importance," said Dr. Nadia Khan, president of Hypertension Canada. "Readings that are too low leave a person at risk of complications and readings that are too high cause needless worry, and even may be a contributing factor behind the recent increase in hypertension-related emergency department visits.

"Choosing the right device is the right first step," Khan said Monday in a release. "Equally important are ensuring the device's cuff fits well upon purchase and using the device in the right way."

Hypertension Canada recommends the acronym SMILES as the correct way to get an accurate blood pressure reading:

Seated, with back and measurement arm supported

Middle of the cuff at heart level, its lower edge 2.5 centimetres above the elbow crease

Legs uncrossed and feet flat on the floor

Empty bladder and bowel before taking blood pressure measurement

Silence for five minutes before and during the measurement. No talking, movement or distractions.