The level of cholesterol in the blood does not depend only on food – Explica .co – Explica

This may be the solution to eat healthier 0:38

(CNN) – Many people worry about cholesterol, and for good reason. More than a third of Americans have high cholesterol, putting them at higher risk for stroke and heart disease, the leading cause of death in the United States. Diet can play an important role in maintaining cardiovascular health, and it is reasonable to think that eating foods loaded with cholesterol will increase cholesterol levels. But the relationship is not that simple.

“I think it makes sense to a lot of people, logically, although most of the data, in the context of current intake, shows that this is not the case,” says Alice Lichtenstein, director of the Cardiovascular Nutrition Laboratory at Tufts University.

The amount of cholesterol in food does not necessarily equal the amount of cholesterol in your blood vessels.

The “biggest culprit”

The nutritional guidelines of the United States Department of Agriculture do not specify a maximum level of cholesterol that we must have in the diet: the recommendation was removed in the publication from 2015 to 2020, and was not included in the new guidelines published for 2021.

This is because, for the most part, the amount of cholesterol we eat is not really a problem.

When thinking about cholesterol in the diet, Lichtenstein stressed that it is important to consider the amount of cholesterol that people typically consume each day. Lichtenstein was on the committee that decided that it was not necessary to limit daily cholesterol intake to 300 milligrams.

Why? Because most of us already did. Women consume, on average, 250 milligrams of cholesterol a day, and men 350 milligrams, according to Lichtenstein. Therefore, the committee did not consider cholesterol to be a “nutrient of public health concern.” (That is, Americans are generally not consuming excessive or insufficient amounts.) A 2019 American Heart Association (AHA) meta-analysis of more than 50 studies found no significant association between dietary cholesterol and cardiovascular risk. In cases where cholesterol intake did appear to increase risk, people ate up to three times the average amount.

“Eating foods high in cholesterol raises blood cholesterol, usually a small but significant amount,” explained Dr. Stephen Devries, a preventive cardiologist and executive director of the Gaples Institute, a nonprofit educational organization, in Deerfield, Illinois. . But the effect of eating foods that contain a lot of cholesterol “may not be as high as might be expected, because most of the cholesterol in the blood actually comes from the body’s own production.” When a lot of cholesterol is consumed, the body usually produces less to compensate.

More worrisome is what usually accompanies cholesterol: saturated fat. Eating lots of foods high in saturated fat increases the production of low-density lipoprotein, or LDL (“bad”) cholesterol, which can build up in your arteries and restrict blood flow to your heart and brain, increasing your chances of suffering. a heart attack or stroke.

“Saturated fats are more to blame for increased cholesterol in the blood in general than cholesterol we get from food,” says Devries.

The role of cholesterol in the body

Animals, including humans, make cholesterol to perform a number of important functions in the body, such as the production of sex hormones, the conversion of sunlight into vitamin D, and the formation of part of the cell membrane. Plants do not manufacture cholesterol, so the cholesterol that we obtain in our diet comes from the consumption of animal products, mainly meat and dairy products. And these are the main dietary sources of saturated fat, what Devries called “a double whammy for raising blood cholesterol levels.”

There is a popular food that bucks this trend: eggs, which are low in saturated fat but very high in cholesterol. A large egg contains 1.6 grams of saturated fat and no less than 187 milligrams of cholesterol. In fact, eggs make up a quarter of the cholesterol in the American diet.

Science cannot decide whether eggs are good or bad for you. Some studies suggest that consuming eggs increases the risk of cardiovascular disease, while others conclude that it does not. One thing that is sometimes overlooked in research that relies on study participants reporting how many eggs they eat is what else they eat.

Although eggs themselves do not contain a lot of saturated fat, their companions at the breakfast table – bacon, sausage, cheese – tend to contain it.

“Now we realize that it is much more important to look at dietary patterns, the big picture,” Lichtenstein said. “You can get confused if you look only at individual foods and not what goes with them.”

Not all foods high in cholesterol are the same

Nutrition experts insist that it is essential not only to eliminate so-called bad foods from the diet, but to pay attention to what you replace them with.

Much of the controversy surrounding the health effects of saturated fats, for example, stems from studying what happens when people cut them down regardless of what they eat instead.

“The risk of each dietary factor has been exaggerated at times and minimized at others, and that’s definitely the case for saturated fat,” Devries said. “If you substitute refined carbohydrates such as sugar or white bread for saturated fat, it has been shown that there is no net health benefit. If saturated fat is replaced by other healthier fats, then there is a clear health benefit with a lower rate of heart disease.

Shellfish, especially shrimp, can be relatively high in cholesterol. But shellfish and fish are a great source of lean protein for people who consume animal products, and they provide essential omega-3 fatty acids, which the body cannot produce on its own. This makes them good substitutes for red meat and poultry.

As for the age-old question of eggs, Devries recommends eating no more than four whole eggs a week – that is, including the yolk, where most of the cholesterol is, along with half the protein.

Lichtenstein is not overly concerned with limiting egg intake for most people, especially since it is a high-quality protein that is easy to store and prepare. Both experts agree that if you eat eggs regularly and don’t have high LDL levels, it’s probably okay to keep doing it.

Healthy eating patterns

There are some people who should be more careful about their consumption of eggs and other foods that are high in cholesterol. Among them are people who have a high cholesterol level (more than 200 milligrams / deciliter) or other risk factors for cardiovascular disease, such as a family history, or those who are hypersensitive to dietary cholesterol, which means that even regular amounts significantly raise your blood cholesterol levels. People with type 2 diabetes should also watch the cholesterol in their food. Each person should talk to their doctor about their particular risks.

For most people, worrying about the cholesterol in certain foods is less significant for your heart health than changing what has already been mentioned before, red meat, whole dairy, packaged foods and sugary drinks, for more vegetables, fruits, nuts, whole grains and legumes. The 2019 AHA meta-analysis recommends switching to healthy eating patterns that emphasize these unprocessed ingredients, such as the Mediterranean diet.

“It’s more important to focus on healthy food categories, rather than talking about individual nutrients like saturated fat or cholesterol,” Devries said. «Most people don’t read labels [nutricionales] and what I’m trying to do is encourage people to eat more foods that don’t have labels. “

So instead of stressing out every time you eat eggs, why not gradually incorporate more leafy greens into your weekly meal plan? Or if you find it more appealing, start by adding fresh seasonal fruit to your dessert a couple of nights a week.

Slowly adopt new eating habits and keep the big picture in mind.

– Amanda Schupak is a science and health journalist in New York City.