A low-carb, high-fat “keto-like” diet may be associated with higher levels of “bad” cholesterol and a double risk of cardiovascular diseases such as clogged arteries, pain, and heart disease, according to a new study. heart and stroke.
“Our study shows that regular consumption of a low-carbohydrate and high-fat diet is associated with increased levels of LDL cholesterol – or “bad” cholesterol – and a higher risk of heart disease,” says Dr. lead author of the study. Iulia Iatan of the Healthy Heart Program Prevention Clinic, St. Paul and the University of British Columbia’s Center for Pulmonary Innovation in Vancouver said in a press release.
“This study makes an important contribution to the scientific literature and to the scientific literature,” said Christopher Gardner, professor of medical research at the Stanford Center for Preventive Research, who conducted clinical trials of the keto diet. found that the harm outweighs the benefit. Gardner was not involved in the study.
“Elevated LDL cholesterol should not be seen as simply an insignificant side effect of the VLCD (very low-carb) or ketogenic diet,” says Gardner. , when compared with more standard dieters.
In the study, researchers identified a low-carb, high-fat (LCHF) diet as 45% of total daily calories coming from fat and 25% coming from carbohydrates. The study, which has not been peer-reviewed, was presented Sunday at the American College of Cardiology Annual Scientific Sessions in conjunction with the World Heart Congress.
“The basis of our study comes from the fact that we will see patients at our preventive cardiology clinic develop severe hypercholesterolemia following this diet,” says Iatan.
Hypercholesterolemia, or high cholesterol, increases a person’s risk of heart attack or other adverse cardiovascular events.
“This led us to wonder about the relationship between this low-carb, high-fat diet, lipid levels, and cardiovascular disease. And so, despite this, there is little data on this relationship.” , she said.
The researchers compared the diets of 305 people on the LCHF diet with around 1,200 people on the standard diet, using health information from the UK database UK Biobank, which has tracked Follow people for at least a decade.
The researchers found that people who followed the LCHF diet had higher levels of low-density lipoprotein, also known as LDL, cholesterol, and apolipoprotein B. Apolipoprotein B is a protein that coats the proteins LDL and cholesterol. may be better at predicting heart disease than elevated levels of LDL cholesterol. Maybe.
The researchers also found that the total fat intake of participants on the LCHF diet was higher in saturated fat and consumed twice as much animal sources (33%) as those in the control group. control (16%).
“After an average of 11.8 years of follow-up – and after adjusting for other risk factors for heart disease, such as diabetes, high blood pressure, obesity and smoking – people followed the LCHF diet more than twice the risk of certain serious cardiovascular events, such as blocked arteries that need to be opened with a stent procedure, heart attack, stroke, and peripheral artery disease,” the researchers said. found, according to the press release.
The researchers said in a statement that their study “could only show an association between diet and increased risk of major cardiovascular events, not a causal relationship.” because this was an observational study, but their findings merit further study, “especially since about 1 in 5 Americans report being on a low-carb, keto-like, or whole diet.” the keto diet.”
Iatan said the study’s limitations include measurement errors that occurred with self-reported dietary assessments, the study’s small sample size and that most participants were British and did not include groups other ethnicities.
The study also looked at the long-term effects of following the diet, while most people who follow a keto-like diet tend to follow it intermittently for shorter periods of time.
Most of the participants — 73% — were women, which Iatan said was “quite interesting to watch, but it also supports the existing literature that women in general tend to conform to more diet, tend to be more interested in changing their body. lifestyle.”
When asked if any groups weren’t harmed by following the LCHF diet, Iatan said how long people diet and whether they lose weight “could counterbalance any increase in weight.” any increase in LDL or not.”
“It’s important to remember that every patient responds differently. And so there’s really some individual variation between responses. What we found was, you know, on average, the disease. People tend to have increased levels of their LDL cholesterol,” she said. .
Dr David Katz, a lifestyle medicine expert who was not involved in the study, said that “there are many different ways to incorporate the LCHF diet and it is very unlikely that all of them will have an effect. similar effect on serum lipids or cardiac events.”
However, he added, “The fact that the LCHF diet was associated with adverse effects in this study is a reality check for people adopting such diets simply because they are in vogue.”
Most health experts say the trendy keto diet, bans carbohydrates that cause your body to burn fat for fuel, cuts out healthy foods like fruits, beans and legumes as well as grains. whole grain cup. On the keto diet, you limit your carbohydrate intake to only 20 to 50 per day – the lower the better. In a word, a medium-sized banana or apple contains about 27 carbohydrates – the all-day allowance.
“The food groups that must be eliminated to achieve a state of ketosis are the main sources of dietary fiber, as well as many important nutrients, phytochemicals, and antioxidants. This is a concern. of many medical professionals who consider VLCD or ketogenic diets to be harmful to long-term health,” Gardner said.
Keto stands for ketosis, a metabolic state that occurs when your liver begins to use stored fat to make ketones for energy. The liver is programmed to do that when your body loses access to its preferred fuel – carbohydrates – and thinks it is starving.
The keto diet has been around since the 1920s, when a doctor stumbled upon it as a way to control seizures in children with epilepsy that didn’t respond to other treatments.
Low-carb diets like keto rely heavily on fat to keep you full. At least 70% of the keto diet will be made up of fat; some say it’s more than 90% similar.
While you can get all that fat from healthy unsaturated fats like avocado, tofu, nuts, seeds, and olive oil, the diet also allows saturated fats like lard. , butter and coconut oil, as well as full-fat milk, cheese, and mayonnaise. Eating foods high in saturated fat increases the body’s production of LDL cholesterol, which can build up inside the arteries and restrict blood flow to the heart and brain.
