E ect of cutting down on the saturated fat we eat on our risk of heart disease
Review questionWe wanted to find out the e ects on health of cutting down on saturated fat in our food (replacing animal fats and hard vegetable fats with plant oils, unsaturated spreads or starchy foods).
BackgroundHealth guidance suggests that reducing the amount of saturated fat we eat, by cutting down on animal fats, is good for our health. We wanted to combine all available evidence to see whether following this advice leads to a reduced risk of dying or getting cardiovascular disease (heart disease or stroke).
Study characteristicsWe assessed the e ect of cutting down the amount of saturated fat we eat for at least two years on health outcomes including dying, heart disease and stroke. We only looked at studies of adults (18 years or older). They included men and women with and without cardiovascular disease. We did not include studies of acutely ill people or pregnant or breastfeeding women.
Key resultsWe found 15 studies with over 59,000 participants. The evidence is current to October 2019. The review found that cutting down on saturated fat led to a 21% reduction in the risk of cardiovascular disease (including heart disease and strokes), but had little e ect on the risk of dying. The review found that health benefits arose from replacing saturated fats with polyunsaturated fat or starchy foods. The greater the decrease in saturated fat, and the more serum total cholesterol is reduced, the greater the protection from cardiovascular events. People who are currently healthy appear to benefit as much as those at increased risk of heart disease or stroke (people with high blood pressure, high serum cholesterol or diabetes, for example), and people who have already had heart disease or stroke. There was no di erence in e ect between men and women. This means that, if 56 people without cardiovascular disease, or 32 people who already have cardiovascular disease, reduce their saturated fat for around 4 years, then one person will avoid a cardiovascular event (heart attack or stroke) they would otherwise have experienced.
Quality of the evidenceThere is a large body of evidence assessing e ects of reducing saturated fat for at least two years. These studies provide moderate-quality evidence that reducing saturated fat reduces our risk of cardiovascular disease.Reduction in saturated fat intake for cardiovascular disease (Review)