Ask a doctor about eggs, and they might tell you they raise your cholesterol levels and could usher you into an early grave.
Yet in gym communities, they are hailed as a super-food.
To get to the bottom of whether eggs are bad or not, one man ate 720 of them in a month to see what really happens when you eat eggs.
Dr Nick Norwitz, a dual doctorate student at Harvard University, found that, contrary to the beliefs of many doctors, his cholesterol levels actually dropped.
Dr Nick Norwitz ate 720 eggs over the course of a month and saw his cholesterol levels fall. He is pictured above with more than 40 cardboard egg boxes from the ‘eggs-periment’
After the month-long experiment that saw him eat the equivalent of 24 eggs per day, or 1,800 calories, his low-density lipoprotein (LDL) levels, or ‘bad’ cholesterol, dropped by 18 percent.
LDL is considered to be ‘bad cholesterol because it can build up as plaque in arteries, increasing the risk of heart disease and stroke.
The other type of cholesterol, called high-density lipoprotein (HDL) or ‘good’ cholesterol, has the reverse effect however by helping to remove excess cholesterol from the bloodstream and transporting it to the liver.
Experts have demonized cholesterol in eggs for decades, warning that eating them may cause a surge in LDL levels and raise the risk of complications.
Dr Norwitz has a PhD in human brain metabolism from the University of Oxford and is completing his medical doctorate at Harvard University.
He first took interest in nutrition science after his battle with ulcerative colitis, inflammation of the bowels where ulcers form, that left him in and out of the hospital and bedridden on some days.
He eventually opted to try the ketogenic diet, where 70 percent of calories come from fats, despite warnings from doctors against using it to treat his condition.
Revealing the decision in STAT in 2021, he said: ‘After one week on a ketogenic diet, my colitis symptoms began to disappear.
‘Over the following months, I came off my colitis medication. [And] two years later, I am still following a ketogenic diet and my colitis remains in remission.’
In the video, which has been viewed more than 160,000 times on YouTube, he said he aimed to show that eating eggs did not cause cholesterol levels to surge.
This graph shows how his cholesterol levels dropped over the four week experiment. They were revealed using blood tests
Dr Norwitz said: ‘I hypothesized that eating 720 eggs in one month, which alone amounts to 133,200mg of cholesterol, would not increase my cholesterol. Specifically, it would not increase my LDL cholesterol.
‘And, indeed, it didn’t, not a smidge.’
He added: ‘Even though my dietary intake of cholesterol more than quintupled, my LDL cholesterol actually dropped.’
Throughout the experiment, he tested levels of cholesterol in his body using blood tests.
Eggs contain about 186 milligrams (mg) of cholesterol each. Other foods high in cholesterol include red meat, shellfish and tropical oils.
Hypothesizing why eggs won’t raise cholesterol, some scientists explain: In the gut, cholesterol binds to receptors on gut cells which prompts the release of a hormone called cholesin.
This travels through the blood to the liver where it binds to a receptor called GPR146, which signals to the liver to produce less LDL, helping to maintain levels in the body.
After the first two weeks of his experiment, Dr Norwitz also decided to start eating 60 grams of carbohydrates per day in the form of fruits such as bananas and blueberries.Â
Dr Norwitz explained the mechanism behind why cholesterol levels had fallen in his body despite him eating so many eggsÂ
He said that in large part it was down to the fact he had also eaten carbohydrates, which his body was using for energyÂ
He explained how eating more carbohydrates can help to reduce cholesterol levels further in the body.
In people on a low carbohydrate diet, levels of LDL tend to surge in their bodies because their system starts to burn fat for energy instead of carbohydrates.
But when someone eats more carbohydrates, the reverse happens — with LDL levels falling in the body because the person is getting more energy from carbs.Â
In the experiment, he ate 60 grams of carbohydrates in bananas, blueberries, strawberries and frozen cherries per day.
That’s equivalent to two bananas a day, or 21 ounces of blueberries.
Commenting on the video, one viewer said: ‘I clicked because I knew that your LDL would not increase and I want share this video with some of family that freaks out that I am eating all these eggs and meat!’
A second added: ‘I’ve eaten eggs almost every day of my 67 years, through all the good/bad, never gave them up. And I’m in very good health, no doctors, no meds.’
