The keto diet is linked to a higher risk of heart attack

• New research shows that the keto diet could cause serious long-term heart health problems.
• Researchers found that a “keto-like” diet was associated with higher levels of “bad” cholesterol and a doubled risk of cardiovascular events such as heart attacks and strokes.
• Experts explain the risks of a keto diet.

Ketogenic or the “keto” diet. has been a topic of conversation in the health world for some time. But as the diet gains in popularity, researchers are finding that the diet has some serious side effects. A new study has found a link between a keto diet and heart health.

A study presented at Annual Scientific Session of the American College of Cardiology in conjunction with the World Congress of Cardiology suggested that a ‘keto-like’ diet may be associated with higher levels of ‘bad’ cholesterol in the blood and a doubled risk of cardiovascular events such as chest pain (angina), blocked arteries requiring stenting, strokes of heart and stroke.

The researchers used data from the UK Biobank and identified 305 participants who indicated that their diet during the 24-hour reporting period met the study’s definition of a low-carbohydrate, low-fat (LCHF) diet. These participants were categorized by age and gender and compared with 1,220 people who reported eating a standard diet.

For this study, researchers defined an LCHF diet as consisting of no more than 25% of calories from carbohydrates and no more than 45% of total daily calories from fat. They called this a LCHF and “keto-like” diet because it’s somewhat higher in carbs and lower in fat than a strict ketogenic diet. They defined a “standard diet” as individuals who do not meet these criteria and have more balanced eating habits.

Compared to participants on a standard diet, those following an LCHF diet had significantly higher levels of LDL, or “bad” cholesterol. After adjusting for other risk factors for heart disease, such as diabetes, high blood pressure, obesity and smoking, the researchers found that people on an LCHF diet had more than twice the risk of having more cardiovascular events major events such as blockages in arteries that needed to be opened with stenting procedures, heart attack, stroke and peripheral artery disease. Overall, the researchers concluded that 9.8 percent of participants on an LCHF diet experienced a new cardiac event, compared with 4.3 percent of those on a standard diet—double the risk for those on the LCHF diet.

What is the keto diet and what risks does it pose to our heart health?

Ketogenic or “keto” diets are high-fat, low-carb diets, so low-carb, in fact, that they cause the body’s metabolism to break down fat and turn it into energy, he explains. Yu-Ming Ni, MD, cardiologist, of non-invasive cardiology at MemorialCare Heart and Vascular Institute at Orange Coast Medical Center. Keto diets have been studied as a means of weight loss for their fat-burning ability, he adds. “A lot of the controversy has been that multiple studies have shown that high-fat, low-carb diets generally have worse cardiovascular outcomes than high-carb, low-fat diets that are plant-based. This study adds to that data.”

So how exactly does keto affect your heart health? There appears to be more inflammation with keto diets in general—high fat is generally more inflammatory, and inflammation is a key factor regulating cardiovascular health and disease, Dr. Ni explains. “Diets high in red meat or processed meat — we certainly have evidence of the pro-inflammatory nature of these foods.”

Keto diets also generally raise cholesterol. This is mostly because the foods you eat are already high in cholesterol, but high-fat, low-carb diets also affect your cholesterol levels, especially if you follow the diet for a long time , says Dr. Ni. He reminds us that “high cholesterol is the number one factor that leads to the development of heart attacks and strokes.”

In general, heart attacks and strokes are linked to three things: cholesterol, inflammation and TMAOexplain Kim Williams, MD, former ACC president and expert in cardiovascular disease prevention and nutrition. “It’s important not to build up these three things in the blood because they promote plaque,” he adds. But when it comes to the keto diet, it raises all three factors. “When you lose weight, your blood pressure goes down, so you’d think your risk of heart disease would also go down, but it doesn’t.”

The bottom line

The keto diet may work for some in terms of short-term weight loss, but these new findings demonstrate the dangers of long-term commitment. It could pose serious risks to your heart health by raising cholesterol levels and promoting inflammation.

For your long-term health, keto is not the way to go, says Dr. Ni. He explains that it is too much stress on the body, too much fat, too much cholesterol. “Long-term ketogenic diets are not as healthy as high-carb, plant-based diets such as Mediterranean diet or The DASH diet. I would advocate those diets for daily sustenance.” However, the key caveat is that the keto diet can be effective for short-term weight loss (3 to 6 months), if that’s what you’re aiming for, Dr. Ni adds.

There are actually different types of keto diets, and not all of them pose the same threat to your heart health. For example, Dr. Williams explains how a vegan or plant-based keto diet can reduce your risk of heart attacks and strokes. “Vegan keto, where you do peanut butter, whole grains and avoid carbs, use olive oil for fat, actually lowers mortality. So it’s not keto itself, it’s keto with animal products.”

If you’re considering the keto diet, be sure to talk to your doctor first, as you could be doing more harm than good to your heart.