The belief that a fatty diet is potentially harmful to human health gained more credence this week when a sixteen-year study found one of the first direct links between a fatty diet and heart disease in women, reports the science journal Nature this week. For women, an extra 100 grams of saturated fat per week increased the risk of heart disease by more than a third.
The report highlights the fact that many studies trying to establish the link between heart disease and dietary fat have tracked groups of men, almost to the total exclusion of women.
"It's an important study," health and lifestyle researcher Brian Cox at the University of Cambridge, UK told Nature. Heart disease, long thought to be a predominantly male affair, is now rising among women and "you have to start from scratch and analyse men and women separately," said Cox.
Those who eat too much fat also tend to eat less fruit and vegetables, points out Cox - and the report does not distinguish between the two factors. Fruit and vegetables are thought to have a protective effect against heart disease.
The study, led by David Boniface, an epidemiologist at the University of Hertfordshire in Hatfield, UK, highlighted the difficulty of pinning down lifestyle risk factors in disease. For men, the effect of diet could not be separated from other risk factors such as smoking, drinking alcohol and taking little exercise.
According to the Nature article, Boniface accepts that a high-fat diet contributes to male heart disease, but says it may be less important for men than for women when compared with genetics and other lifestyle factors. Finding out how much people eat is also difficult, because they tend to adjust what they report when questioned.
In 1984, the researchers interviewed 2,700 randomly selected British men and women aged between 40 and 75 about their fat intake. Subjects were subsequently monitored for death from coronary heart disease.
Full findings are published in the recent issue of the European Journal of Clinical Nutrition, 56, 786 - 792, (2002).