A common question that people ask about the keto diet is if it can increase or reduce your risk of heart disease.
Some authorities will warn you that a low-carbohydrate diet that avoids whole grains and embraces fat is dangerous for heart health — but the research doesn’t agree.
Heart disease, also known as coronary heart disease (CHD) or cardiovascular disease, is the leading cause of death for both men and women in the United States[*].
This life-threatening condition is caused by a buildup of plaque in your arteries, made up of cholesterol, fat, calcium, and other substances. Your arteries are essential for carrying blood, oxygen, and nutrients to other parts of your body, and when plaque builds up it makes it more difficult to nourish the cells and tissues relying on their transport.
In a process known as atherosclerosis, the plaques keep growing bigger, and can eventually begin to narrow and block blood flow to your heart and around your body. Over time, this can weaken your heart muscle and lead to permanent damage, known as heart failure, which is a condition where your heart can no longer pump normally.
Eventually, when blood flow to your heart is blocked enough, your heart becomes starved of oxygen and you have a heart attack[*].
Cholesterol plays a key role in the progression of heart disease, as this waxy substance is a strong contributor to the plaques that form in your arteries.
Cholesterol doesn’t travel around your body on its own, instead, it’s packaged into something called lipoproteins, which are made of protein and fat. The primary function of lipoprotein is to carry fatty acids and cholesterol throughout your body and deliver them to specific tissues.
There are two primary types of lipoproteins, including LDL (low-density lipoprotein) and HDL (high-density lipoprotein). HDL is known as the “good” cholesterol, while LDL is known as your “bad” cholesterol.
It may sound confusing, but the terms “lipoprotein” and “cholesterol” are often used interchangeably due to the fact that cholesterol is carried in lipoproteins, and the fate of the cholesterol depends on which type of lipoprotein they’re carried in.
So what makes LDL bad, and HDL good? LDL is known to contribute to heart disease, while HDL helps to prevent it.
To understand this in more detail, we have to look at the function of LDL vs HDL.
HDL travels through your body and picks up cholesterol to transport it to your liver. Once in your liver, cholesterol is eliminated from your body in the form of bile acids. Goodbye cholesterol.
LDL, on the other hand, picks up cholesterol and carries it to your arteries where it can contribute to plaque formation.
It’s healthy to have both types of cholesterol (or lipoproteins) in your body, but the ratio of each is what really matters. Having more HDL cholesterol means that more cholesterol is leaving your body than circulating to your arteries[*].
There are several modifiable and nonmodifiable risk factors for heart disease.
Some non-modifiable factors include[*]:
- Age — men aged 45 and older and women aged 55 and older are at greater risk for heart disease
- Ethnicity and race — certain ethnic backgrounds can contribute more or less to the risk for heart disease. For instance, African Americans are more likely than Caucasians to have heart disease, and Hispanic Americans are less likely than both groups.
- Family history — If someone in your family has had heart disease, it increases your risk.
- Sex — Heart disease tends to be more prominent in men, but conditions like diabetes raise the risk more for women.
Of course, all of these non-modifiable factors don’t necessarily set you up for heart disease, they only increase the risk if your modifiable factors aren’t in order. The modifiable risk factors for heart disease include[*]:
- High blood pressure
- Poor diet
- High cholesterol
- Physical inactivity
- Diabetes/ poor insulin sensitivity
- Smoking tobacco
- Alcohol consumption
Heart disease is one of the most preventable causes of death, as lifestyle factors play a significant role in its progression.
Depending on the stage of your heart disease, it may also be reversible as long as you’re managing the risk factors and your current symptoms properly.
Diet, exercise, stress management, and lifestyle factors like getting enough sleep, not smoking, and limiting alcohol intake can all play a role in managing and preventing heart disease[*].
As the keto diet has become more popular and keto research has become more robust, common misconceptions have finally been laid to rest.
One popular argument against keto was that the increase in fat consumption would set you up for heart disease. This fallacy came from the idea that saturated fat would increase your LDL cholesterol, which in turn would contribute to atherosclerotic plaques, heart disease, and heart attacks.
Luckily, research in the last several years has turned this theory on its head as the original studies that made authorities like the American Heart Association warn against saturated fat have been largely debunked[*][*].
Instead, many people are turning to a high-fat, low-carb diet to enhance heart health and combat some of the most significant risk factors for heart disease.
Why? Because the research shows that a keto diet may support heart health in the following ways:
#1 Lowers Cholesterol
High levels of LDL cholesterol, with low levels of HDL cholesterol, are two risk factors for heart disease. While the old story of saturated fat would have you believe that the ketogenic diet increases your LDL cholesterol — the research begs to differ.
Studies show that on a long-term ketogenic diet, LDL cholesterol levels plummet, while HDL cholesterol increases significantly. This means that when you follow a keto diet, more cholesterol is sent to your liver to be processed and eliminated, and less is deposited in your arteries[*].
#2 Combats Obesity
Obesity is a well-known risk factor for heart disease as it increases many of the other risk factors like high blood pressure, high cholesterol, and inflammation[*]. When you cut carbs and increase the healthy fat in your diet, weight loss is a common side effect.
Research shows that a ketogenic diet can help you combat markers for obesity by lowering body weight and BMI[*]. In one study of over 19,000 patients, researchers reported that following a ketogenic diet led to rapid weight loss (57% of which came from fat) with no significant adverse effects[*]. Statistically, that is a huge win.
Furthermore, due to the makeup of the diet, when you eat keto your cravings for carbs and sugar significantly decrease which makes it much easier to stick to a healthy eating plan[*.]
#3 Reduces Inflammation
Doctors used to exclusively look to high cholesterol levels as a risk factor for heart disease. More recent research suggests that inflammation is the main cause.
Ketones themselves exhibit anti-inflammatory properties, which makes the bridge between animal models and human studies quite plausible[*].
#4 Reduces The Risk For Type 2 Diabetes
Diabetes is marked by uncontrolled levels of glucose in your blood due to insulin resistance, and being diabetic is one of the primary risk factors for heart disease. What’s the connection?
Over time, high levels of blood glucose can damage your blood vessels and the nerves that control your heart. Therefore, the longer you have uncontrolled diabetes, and the more elevated your blood sugar, the higher your chances are of developing heart disease[*].
When you follow a ketogenic diet, you naturally eliminate the risk of high blood sugar because you’re no longer consuming a significant amount of carbohydrates. No carbs mean no high blood sugar, and no high blood sugar means no risk of damage to your blood vessels.
Research shows that a keto diet is so effective at reducing blood sugar levels that many people are able to come off of their diabetes medications entirely[*].
Being in a state of ketosis is quickly emerging as one of the best ways to support heart health. Despite the fears that may loom around a high-fat diet, consuming high-quality foods like grass-fed red meat, olive oil, and lots of low-carb veggies can mitigate cardiovascular risk factors.
This heart-healthy way of eating promotes health benefits like reduced inflammation, improved blood sugar control, improved blood lipids, and weight loss.