Eggs are high in saturated fats and dietary cholesterol and have been associated with increased risks for heart disease, diabetes, colorectal cancer and prostate cancer.
Around 60% of calories from eggs come from fat - big portion of which is from saturated fat.
Breakdown on Cholesterol
You do not need cholesterol in your diet as your body is more than capable of making enough to meet the body’s needs.
Dietary cholesterol does impact your blood cholesterol levels. The effect the dietary cholesterol has depends on our diet. If our diet is already high in cholesterol and saturated fat, adding more cholesterol does not have as much effect. However, when it is added to a healthy diet low in dietary cholesterol, the blood cholesterol levels do increase, especially LDL cholesterol (bad cholesterol).
HDL’s function is more important than just the levels. HDL (good cholesterol) is supposed to be anti-inflammatory but when diet is high in saturated fats, it can become pro-inflammatory.
Foods high in cholesterol like eggs can promote LDL oxidation and increase cardiovascular disease risk.
Heart Disease
The saturated fat and cholesterol from eggs play a role in the connection between eggs and heart disease. High blood cholesterol levels lead to thickening of walls of blood vessels which restrict blood flow to organs like the heart and the brain. Eggs also contain choline which in our body gets converted to a toxic compound called TMAO (trimethylamine oxidase), which increases the risk for heart attack and stroke. A review looking at 14 research studies found people consuming eggs frequently had higher risk for heart disease and stroke. A study found people eating one egg a day (or seven eggs a week) to have an 80% higher coronary artery calcium scores, a measure of heart disease risk.
High cholesterol is also associated with other health problems such as breast cancer, inflammation, joint pain and infertility. Furthermore, when consuming foods high in cholesterol, you're consuming saturated fat and saturated fat itself increases cholesterol levels increasing risks for worse health outcomes over long-term.
Diabetes
Egg consumption has also been linked to higher diabetes risk as it contributes to higher levels of cholesterol and saturated fat. A diet high in saturated fat increases insulin resistance, since saturated fat can interfere with insulin's ability to transport glucose into cells from blood. Egg consumption has also been found to increase risk for gestational diabetes.
Cancer
Consumption of eggs may also increase risk for certain cancers including breast, colon, prostate, rectal and bladder. It has been suggested that TMAO (described above) promotes the growth of cancer, especially in breast, prostate and ovary cancer. Only consuming 1.5 eggs per week has been shown to increase the risk for colon cancer by five times. Even moderate consumption of eggs may triple the risk of bladder cancer. A 2011 Harvard study found that egg consumption to have a link with prostate cancer as well. Only 2.5 eggs per week showed men to increase their risk of lethal form of prostate cancer by 81% in comparison with men who consumed less than half an egg per week. The possible explanation is the high amounts of cholesterol and choline in eggs.
Egg Whites
People often switch to egg whites to lower their intake of cholesterol and saturated fat while hoping to increase their protein intake. High protein, especially from animal protein, has been linked to higher risk of mortality and various diseases including certain cancers, kidney disease and kidney stones. Egg whites are not necessary to meet protein requirements. Plant based protein options like legumes, whole grains, nuts, seeds and even some vegetables not only add protein to your diet but also fiber, antioxidants, phytochemicals, vitamins and minerals, which all promote health.
Egg Substitutes graphic for cooking and baking can be found here. Also, check out the chickpea omelette recipe and the tofu scramble recipe.
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