In Yellowknife, reader Sarah Mann asks: “What’s the new recommendation about eggs? How many can we eat per day?” Globe Health columnist and registered dietitian Leslie Beck says, “eggs have long been vilified for their high cholesterol content. One large egg has 183 milligrams of cholesterol, almost two-thirds of a day’s worth for healthy people.” She says a 2013 study about eggs “might make you swap sunny-side up for a whites-only omelette.” We asked Beck to revisit her 2013 article on the subject and provide an up-to-date explanation of eggs’ bad rap – and current dietary recommendations:
A 2013 report, published online in the American Journal of Clinical Nutrition, concluded that eating an egg a day – yolk included – did not increase the risk of cardiovascular disease in healthy people.
The bad news: Egg eaters were more likely to develop type 2 diabetes. And among people who already had diabetes, an egg-a-day habit substantially upped the likelihood of a heart attack or stroke. That said: Cholesterol is essential for life. It’s needed to build cell membranes, form healthy nerve fibers and make vitamin D and hormones such as estrogen and testosterone.
Although high blood cholesterol is an established risk factor for a heart attack and stroke, the link between cholesterol in foods and cardiovascular disease remains unclear. Most studies have found that dietary cholesterol has little, if any, impact on blood-cholesterol levels.
While eggs may have little effect on your fasting blood-cholesterol level, that may not be the case for your “after-meal”, or postprandial, blood cholesterol. (Fasting blood cholesterol is measured after consuming no food or drinks, with the exception of water, for nine to 12 hours.)
There is mounting evidence that, depending on what you eat, postprandial blood fats can damage blood vessels and promote atherosclerosis (hardening and narrowing of the arteries). Small studies have shown that eating a cholesterol-rich meal can enhance the blood-cholesterol-raising effects of saturated (animal) fat and increase the chance that your LDL (bad) blood cholesterol becomes oxidized.
So what are we to make of all this? Are eggs off the menu? Most people don’t have to worry about eating an egg yolk to two each day; the evidence that the amount of cholesterol you eat raises LDL blood cholesterol is weak.
So weak, in fact, that scientific advisory panel for the 2015 iteration of the Dietary Guidelines for Americans is recommending the decades-long recommendation to avoid eating foods high in cholesterol be dropped.
Some people, though, are sensitive to the blood cholesterol-raising effect of food cholesterol. People with diabetes and those with heart disease should limit their intake of egg yolks to four per week (some experts advise avoidance).
Instead of eating a two-egg omelette with 266 milligrams of cholesterol, have a cholesterol-free white-only omelette for a good source of protein, riboflavin (a B vitamin) and selenium. Try a cholesterol-free egg product sold in the egg case at grocery stores.
Keep in mind that there are variables we do not yet know. It’s possible that consuming antioxidant-rich foods (e.g. berries, citrus fruit, red peppers, spinach, green tea) or anti-inflammatory foods (e.g. salmon, chia seeds, ground flax, walnuts) with an egg could mitigate the harmful postprandial blood fat effects.
But most of all, let’s not forget that preventing cardiovascular disease is about a whole lot more that cutting back on egg yolks. Limiting refined (white) starchy foods and added sugars, reducing trans fats, emphasizing monounsaturated fats (e.g. olive oil, avocado, almonds), increasing omega-3 fats from fish oil, limiting sodium intake, getting regular exercise and maintaining a healthy weight are key strategies to guard against heart disease and stroke.