For a long time, coronary heart disease is thought to be caused by saturated fat clogging arteries.
However, a new study suggests that this idea is wrong. Coronary heart disease is a chronic inflammatory condition, and the risk can be reduced from healthy lifestyle interventions.
Recent research has shown no link between saturated fat consumption and mortality from coronary heart disease.
In this study, people were asked to follow a low-fat diet (37% fat) or an energy-unrestricted Mediterranean diet (41% fat) supplemented with extra virgin olive oil or nuts.
The results showed that these people had 30% reduction of heart disease compared to people who followed a typical western diet. Thus, healthy diets can help improve heart health.
Researchers also found that the LDL cholesterol risk has been exaggerated.
In the reanalysis of unpublished data from the Sydney Diet Heart Study and the Minnesota coronary experiment, researchers found that replacing saturated fat with linoleic acid containing vegetable oils increased mortality risk despite significant reductions in LDL and total cholesterol (TC).
In fact, a high TC to high-density lipoprotein (HDL) ratio is the best predictor of cardiovascular risk. A high TC to HDL ratio is also a surrogate marker for insulin resistance.
And in those over 60 years, LDL cholesterol is not associated with cardiovascular disease and is inversely associated with all-cause mortality.
A high TC to HDL ratio drops rapidly with dietary changes such as replacing refined carbohydrates with healthy high fat foods.
In addition, physical activity can effectively reduce heart disease risk.
Compared with physically inactive people, those who walk briskly at or above 150min/week can increase life expectancy by 3.4–4.5 years independent of body weight.
Regular brisk walking may also be more effective than running in preventing coronary disease.
And just 30min of moderate activity a day more than three times/week strongly improves insulin sensitivity and helps reverse insulin resistance within months in sedentary middle-aged adults.
This occurs independent of weight loss and suggests even a little activity goes a long way.