Healthy blood pressure and cholesterol levels were not guaranteed at any age or level of fitness, Dr White said.
"It's not unusual to see patients in their early 40s in the Coronary Care Unit," he said.
"Unless your blood pressure or cholesterol is checked, you don't know."
Those with a family history of heart disease are at greater risk of having a heart attack, even at a young age, Dr White warned.
"It's a lifetime disease, it starts in utero."
Men who hit their 40s and decide to make lifestyle changes are on the right track, Dr White said, but must be careful not to exercise too vigorously at first.
"If people do triathlons when they are not fit, that's not a good idea.
"[Fitness] has to be gradually built up."
Dr White recommended regular blood pressure checks and cholesterol maintained at "really low levels".
"Stormin" Norman Berryman died of a heart attack in Australia overnight. He played one test for the All Blacks, against South Africa in 1998.
Berryman had been recently living in Perth working as a forklift driver. He is survived by six children.
Heart attack facts
1.
Cardiovascular disease (heart, stroke and blood vessel disease) is still the leading cause of death in New Zealand, accounting for 30 per cent of deaths annually.
2.
Every 90 minutes a New Zealander dies from heart disease and many of these deaths are preventable.
3.
One in twenty adults have been diagnosed with heart disease. That's more than 165,000 New Zealand adults.
4.
It is estimated that 5,000 people die prematurely from smoking each year - this equates to around 12 people a day dying from smoking.
5.
How much you move, what you eat and whether you smoke are important factors that influence your risk of heart disease.
(Source: New Zealand Heart Foundation)
