For many people, maximizing longevity means minimizing heart disease risk. Heart disease is, after all, the world’s leading cause of death. The best way to reduce heart disease risk, including heart failure risk, is to improve the risk factors that drive the disease process, most specifically obesity, diabetes, high blood pressure, high LDL, and inflammation. This is where intermittent fasting comes in. Researchers have shown that intermittent fasting, in both animals and humans, triggers a cascade of health benefits, especially positive changes for the heart. Here you’ll learn how, exactly, fasting improves heart health.
But first, let’s explore the basics of heart disease.
What Is Heart Disease?
Heart disease, or cardiovascular disease, refers to problems with the circulatory system. These problems include:
- Insufficient blood flow to the brain (i.e., stroke)
- The heart not pumping enough blood to meet the body’s needs
- A buildup of plaque that narrows the arteries (this is called atherosclerosis)
Let’s talk about atherosclerosis because it’s the crux of heart disease. Atherosclerosis is often called the “silent killer” because it builds over a lifetime with no noticeable symptoms. Then one day, a heart attack occurs. Often, this event is fatal.
The main drivers of atherosclerosis include:
- Low-density lipoproteins (LDL) particles (they transport lipids throughout the body)
- High blood pressure
Each of these factors contributes to heart disease in tandem with the others. The LDL particle, for instance, is the particle that burrows into the arterial wall, oxidizes, and precipitates the formation of atherosclerotic plaques.
But if inflammation is low, the plaques — which are basically clumps of immune particles — can’t form. And if blood pressure is low, LDL particles are less likely to bump into (and stick to) the arterial wall in the first place.
Fortunately, many heart disease risk factors are within human control. Let’s explore how fasting works, then we’ll see how it might help.
How Intermittent Fasting Works
Intermittent fasting (IF) just means an eating pattern that takes regular breaks from food intake for a period of time. It’s about time-restricted feeding and fasting periods. It really is that simple.
Generally, when people partake in intermittent fasting, they eat a healthy diet during feeding times, whether it’s a ketogenic diet or a Mediterranean diet (which is NOT a keto diet). There is also some element of calorie restriction; it’s not eat an entire cake during your eating period, but rather proper calorie intake based on your ideal macros (based on your age, body weight, and other factors) and a lower amount of carbohydrates (sugar). In between, during the long periods without food, the consumption of clear, very low- or no-calorie liquids, especially those that keep your electrolytes and potassium up.
The most common forms of IF are:
- 12/12: A daily 12-hour overnight fast
- 16/8: 16 hours of fasting, 8 hours of the day when you eat
- One-Meal-A-Day (OMAD): All your daily calories in one sitting
- 5/2: 5 days of normal eating with 2 non-consecutive days of 0-25% of calories
- Alternate day fasting (ADF): Every other day you reduce calories by 75-100%
Western culture, however, isn’t big on intermittent fasting. Snacks are available 24/7. There’s always something to nibble on.
The thing is, when you eat constantly — especially if you’re eating sugar — your blood sugar levels (blood glucose) levels stay chronically elevated. Not only does this prevent you from burning fat; it also increases your risk for most of the major diseases. In fact, a diet of constant sugar largely explains why millions of Americans are diabetic or prediabetic.
By fasting intermittently, your blood sugar and insulin levels stay low. Low insulin, in turn, signals your body to start burning fat and producing ketones. For this reason, many see ongoing intermittent fasting as an antidote to diabetes. (And diabetes is basically a bundle of heart disease risk factors).
6 Ways Fasting Improves Heart Health
Now that you’ve learned the basics, here are six ways fasting may decrease heart disease risk.
#1: Diabetes reversal
Type 2 diabetes is a metabolic disorder marked by high blood sugar, high insulin, high blood pressure, high triglycerides, and obesity. It’s caused by high sugar diets and sedentary lifestyles, which is why America has a diabetes epidemic. Why is this important for heart health? Because diabetes and heart disease are closely linked. In fact, heart disease is the main cause of death for diabetics.
The research on fasting for reversing diabetes is early but promising. One 2018 study published in the Journal of the American Medicine Association found that 5:2 fasting significantly reduced blood sugar (HbA1c) in 70 patients with type 2 diabetes.
#2: Weight loss
Obesity is a primary heart disease risk factor. When an obese person loses weight, their heart disease risk decreases. There are a couple of ways intermittent fasting helps with weight loss. First, fasting lowers blood sugar and insulin levels — a metabolic step necessary to utilize (burn) body fat as energy. Also, many intermittent fasting regimens restrict calories. When you eat less energy than you use, you’re likely to lose weight.
A growing body of research suggests that fasting, in various forms, is effective for losing weight. After reviewing the pertinent literature, the authors of one 2018 review concluded that “intermittent fasting was effective for short-term weight loss among normal weight, overweight and obese people.”
#3: Lower blood pressure
High blood pressure, or hypertension, has been known to increase heart disease risk for decades. It’s a widespread condition, affecting about 86 million US adults. Intermittent fasting has been shown, in multiple human trials, to improve hypertension. In one 2011 study, six months of 5:2 fasting significantly reduced blood pressure in overweight women.
#4: Lower LDL
Think of low-density lipoprotein (LDL) particles as trucks carrying precious cargo — fat and cholesterol — throughout your body. But when there are too many trucks on the road, more accidents occur. In other words, a high number of LDL particles increases the risk of atherosclerosis.
Fasting can lower LDL, at least in obese and diabetic populations. In one study, alternate day fasting lowered LDL cholesterol (a proxy for LDL particles) in obese people. It’s important, however, to differentiate between LDL cholesterol (LDL-C) and LDL particle number (LDL-P). LDL-P counts the number of LDL particles per unit of blood, while LDL-C measures the amount of cholesterol (a separate molecule) within LDL particles. While they are usually correlated, LDL-P appears to track risk more accurately.
#5: Lower inflammation
When an LDL particle sticks to the artery wall, immune particles rush to the site, cause an uproar, and eventually form plaques. The point being: Without inflammation, you wouldn’t have atherosclerosis. Because of this, many protocols target inflammation to reduce heart disease risk. Even statins (best known for lowering cholesterol) have a powerful anti-inflammatory effect.
Can fasting reduce inflammation? The research suggests yes. One study published in Nutrition Journal, for instance, found that 12 weeks of alternate-day fasting decreased CRP (a marker of inflammation) in normal weight and overweight adults.
#6: Lower triglycerides and higher HDL
Triglycerides are tiny bundles of fat that circulate in the blood for energy. Lower triglycerides are linked to lower heart disease risk.
The high-density lipoprotein (HDL) molecule cruises the bloodstream to remove oxidized (or “bad”) cholesterol from blood vessel walls. Higher HDL is linked to lower heart disease risk.
Putting it all together, the triglyceride to HDL ratio has become a common tool in the CVD risk assessment toolkit. A lower ratio is correlated with lower risk. And alternate day fasting, it’s been shown, both reduces triglycerides and raises HDL levels.
What else can improve the triglyceride to HDL ratio? If you guessed the ketogenic diet, you’d be correct!
The Final Word
There are a number of benefits of intermittent fasting. If you want to take care of your heart, focus on improving your risk of heart disease. Practically speaking, this means minimizing obesity, diabetes, inflammation, high blood pressure, and high LDL. All these risk factors accompany the sugary diet and sedentary lifestyle so common in modern society. The effects of intermittent fasting should help with heart wellness.
Intermittent fasting, it’s been shown, can reverse these risk factors. And by doing so, it appears to decrease heart disease risk. More research is needed in the healthcare community and cardiology sector, however, before we can draw firm conclusions.