In a new Scientific Advisory, researchers suggest that reducing dietary cholesterol by focusing on overall heart-healthy diets remains good advice for keeping artery-clogging LDL cholesterol levels healthy.
Heart-healthy diets are rich in vegetables, fruits, whole grains, low-fat dairy products, poultry, fish, legumes, vegetable oils, and nuts.
They also limit salt, red and processed meats, refined-carbohydrates and added sugars.
These diets are relatively low in dietary cholesterol and support healthy levels of artery-clogging LDL cholesterol.
The research does not support a specific numerical limit on cholesterol from food.
The Advisory is from the American Heart Association.
Much of the cholesterol in the blood is manufactured in the liver and used for building cells.
However, foods such as full-fat dairy products and fatty cuts of red and processed meats contain relatively high amounts of cholesterol and are also usually high in saturated fat, which may cause an accumulation of cholesterol in the blood.
Too much cholesterol in the blood contributes to the formation of thick, hard deposits on the inside of the arteries, a process that underlies most heart diseases and strokes.
Scientific research about the role of dietary cholesterol has not conclusively found a link between dietary cholesterol and higher LDL cholesterol at levels currently consumed.
The differences in findings may be based on the way studies about diet are designed and the absolute amount of cholesterol-fed.
For example, evidence from observational studies conducted in several countries generally does indicate a significant association between dietary cholesterol and cardiovascular disease (CVD) risk.
Observational studies, however, are not designed to prove cause and effect – they identify trends, often based on study participants filling out questionnaires about what they eat.
Study findings from observational studies could be impacted by factors such as the difficulty of teasing out the specific effect of dietary cholesterol versus saturated fat because most foods that are high in saturated fats are also high in dietary cholesterol.
In the Advisory, the team conducted a meta-analysis of previous studies and found that there was a dose-dependent relationship between dietary cholesterol and higher levels of artery-clogging LDL cholesterol when the range of dietary cholesterol tested was beyond that normally eaten.
This relationship persists after adjustment for dietary fat type.
The team says eating a nutrient-rich diet that emphasizes fruits, vegetables, whole grains, low-fat or fat-free dairy products, lean cuts of meat, poultry, fish or plant-based protein, nuts, and seeds.
Saturated fats – mostly found in animal products such as meat and full-fat dairy, as well as tropical oils – should be replaced with polyunsaturated fats such as corn, canola or soybean oils.
Foods high in added sugars and sodium (salt) should be limited.
In general, egg intake was not strongly linked to the risk of cardiovascular disease in the studies that were examined.
It is reasonable to eat one whole egg (or its equivalent such as 3 ounces of shrimp) daily as part of a heart-healthy diet for healthy individuals.
The study is published in the Association’s premier journal Circulation.
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