Is intermittent fasting good for your heart?
It’s probably no surprise that your heart is pretty dang important. The constant beating of your heart circulates oxygen-rich blood to each organ, muscle, and tissue down to the very last cell. Heart damage or disease can rapidly affect your entire body.
So, it pays to take good care of your heart — as well as the associated structures, like blood vessels — that do all of this crucial work.
Unfortunately, cardiovascular diseases like heart disease and stroke are some of the most common health concerns, especially as we get older.[1]
Fortunately, for some people, intermittent fasting may be a simple, drug-free way to lower the risk — and that’s what we’ll explore in this article.
Why heart health matters
Heart disease is the leading cause of death in the United States.[2] Every year, approximately 800,000 people in America experience a heart attack.[2] About one in five heart attacks is silent, meaning you might not even know you’re having a heart attack until the damage is done.
Oof, that’s some scary stuff!
Here’s some good news: while several factors contribute to heart disease, some of those are in your control.
So, while you can’t control things like your genes or your age, you can control many heart-healthy behaviors.
Like, say, practicing intermittent fasting.
How intermittent fasting may improve heart health
Intermittent fasting can potentially improve heart health and decrease heart disease risk in several ways:[3]
- addressing a collection of risk factors known as metabolic syndrome
- improving the overall lipid profile
- potentially decreasing inflammation
- potentially improving heart recovery after damage
Intermittent fasting may help address metabolic syndrome
Hearts don’t operate in isolation. Other health conditions — such as insulin resistance, diabetes, high levels of inflammation, or high blood pressure — can also affect heart health.
In combination, these and other risk factors are known as metabolic syndrome. The term “metabolic” refers to the biochemical processes that are part of your body’s natural functioning: eating, energy creation, and the circulation of oxygen-rich blood.
By tackling these areas, you can potentially lower your overall risk of heart disease.
Thus, intermittent fasting can be a heart-healthy lifestyle change because
- it helps your body use fat for fuel without compromising too much lean body mass, helping you lose weight and improve overall metabolic health;[4] and
- fasting helps you produce and store insulin more efficiently, which reduces your risk of insulin resistance.[5]
You can see when your body switches to using fat for fuel by using your Simple fasting timer. We’ll tell you when this important metabolic shift has occurred. It’s pretty cool if we do say so ourselves! If you’re ready to get started, take our Simple quiz, and we’ll get you set up to crush those health goals.
Intermittent fasting may improve your lipid profile
A lipid profile is a common test that doctors might do to assess heart disease risk. This blood test looks at levels of particular fats and proteins in the blood, known as lipoproteins, cholesterol, and triglycerides.
Some types of fats and proteins are known as “cloggers” — in other words, they can clog up our blood vessels and increase the risk of heart disease. Others, like the “good” HDL, are “cleaners” — in other words, they’re like the garbage trucks that go along and tidy things up.
Fasting may play a role in reducing “bad” LDL cholesterol and improving the overall lipid profile of people with uncontrolled cholesterol levels.[6]
Intermittent fasting may lower inflammation
Inflammation is actually a big part of heart disease. When LDL plaques start sticking to the inside of blood vessels, they can become inflamed. This inflammatory process can cause further damage and blockage. The good news?
- Fasting may help lower markers of systemic inflammation, like C-reactive protein (CRP).[7]
While the jury is still out on just how much fasting helps with inflammation, the results are promising.
Intermittent fasting may improve heart recovery
Heart muscles can be damaged by more preventable conditions, like high blood pressure and diabetes.
When your heart muscles become damaged, it’s more difficult for your heart to effectively pump blood through your body. Intermittent fasting may be able to help your heart recover.
As early as the 1960s, doctors were exploring fasting as a possible treatment for helping to alleviate cardiotoxicity.[8] More recent data suggest that fasting may help protect against damage from heart attacks.[9] However, we need more research in this area to be able to validate this claim.
Combining fasting with other lifestyle changes: bonus benefits!
Intermittent fasting pairs well with other heart-healthy behaviors like:
- drinking more water
- eating more mindfully
- making wiser food choices
- getting regular exercise
For instance, one study found that for people with a higher body mass index, combining fasting and endurance exercise helped them lose weight and improve their cardiovascular health indicators (in this case, the lipid profile of things like cholesterol) much better than either fasting or exercise alone.[10]
Try using our Simple food tracker to get personalized insights on your foods and drinks. This can help you get the most out of your fasting program by ensuring you’re also making heart-healthy nutrition choices. Take our Simple quiz to get started today!
What are the side effects of intermittent fasting?
Intermittent fasting doesn’t have life-threatening or serious side effects. Typically, the most common intermittent fasting side effects of fasting include hunger, fatigue, low blood sugar, and possible changes in your bowel movements while your body adjusts.
Intermittent fasting has more benefits than risks when it comes to your heart health.
That said, while short-term fasting is safe, longer fasts may have the opposite effect on heart health. We recommend no longer than a 20-hour fast, and most people will feel and function best with something like a 12- to 16-hour fasting period.
Fasting isn’t effective or right for everyone. We recommend talking to your healthcare provider before changing your eating pattern, especially if you:
- are pregnant, breastfeeding, or trying to conceive
- have a history of or are currently experiencing disordered eating
- have a medical condition, especially those that impact the pancreas, liver, thyroid, or gallbladder
- have a BMI less than 18.5
- are under the age of 18, or 80 years old or more
- are prescribed medication
If you’ve been given the green light, we’re here to get you across your fasting finish line. Take our Simple quiz to learn what fasting schedule might be a good fit for you and your health goals.
No, but for many people, losing weight does help improve their cardiovascular risk profile. Even small amounts of weight loss (5% to 10% of body weight) are often enough to improve many clinical markers.[11]
Before starting any fasting regimen, anyone with existing heart conditions should consult their healthcare provider. Fasting may affect medication schedules and blood pressure, so it’s crucial to get personalized medical advice.
In particular, anyone taking medication should consult their healthcare provider before attempting intermittent fasting. Fasting can affect how medications are absorbed and metabolized, so adjustments to medication schedules might be necessary.
Some studies suggest that intermittent fasting may help lower blood pressure in people with a higher body mass index, potentially due to weight loss and improved insulin sensitivity.[12]
However, we recommend that if you currently have blood pressure issues, you consult your healthcare provider before making any significant lifestyle changes.
- Vaduganathan M, Mensah GA, Turco JV, Fuster V, Roth GA. The global burden of cardiovascular diseases and risk: A compass for future health. J Am Coll Cardiol. 2022 Dec 20;80(25):2361–71.
- CDC. Heart disease facts [Internet]. Centers for Disease Control and Prevention. 2023 [cited 2023 Aug 22]. Available from: https://www.cdc.gov/heartdisease/facts.htm
- Dong TA, Sandesara PB, Dhindsa DS, Mehta A, Arneson LC, Dollar AL, et al. Intermittent fasting: A heart healthy dietary pattern? Am J Med. 2020 Aug;133(8):901–7.
- Gu L, Fu R, Hong J, Ni H, Yu K, Lou H. Effects of intermittent fasting in human compared to a non-intervention diet and caloric restriction: A meta-analysis of randomized controlled trials. Front Nutr. 2022 May 2;9:871682.
- Yuan X, Wang J, Yang S, Gao M, Cao L, Li X, et al. Effect of intermittent fasting diet on glucose and lipid metabolism and insulin resistance in patients with impaired glucose and lipid metabolism: A systematic review and meta-analysis. Int J Endocrinol. 2022 Mar 24;2022:6999907.
- Yang F, Liu C, Liu X, Pan X, Li X, Tian L, et al. Effect of epidemic intermittent fasting on cardiometabolic risk factors: A systematic review and meta-analysis of randomized controlled trials. Front Nutr. 2021 Oct 18;8:669325.
- Malinowski B, Zalewska K, Węsierska A, Sokołowska MM, Socha M, Liczner G, et al. Intermittent fasting in cardiovascular disorders: An overview. Nutrients. 2019 Mar 20;11(3).
- Strebel R, Bajusz E, Selye H. Fasting as a protective stressor against the potential cardiotoxic action of various agents. Cardiologia. 1962;41:179–90.
- Vemuganti R, Arumugam TV. Molecular mechanisms of intermittent fasting-induced ischemic tolerance. Cond Med. 2020 Feb;3(1):9–17.
- Bhutani S, Klempel MC, Kroeger CM, Trepanowski JF, Varady KA. Alternate day fasting and endurance exercise combine to reduce body weight and favorably alter plasma lipids in obese humans. Obesity . 2013 Jul;21(7):1370–9.
- Brown JD, Buscemi J, Milsom V, Malcolm R, O’Neil PM. Effects on cardiovascular risk factors of weight losses limited to 5-10. Transl Behav Med. 2016 Sep;6(3):339–46.
- Silva AI, Direito M, Pinto-Ribeiro F, Ludovico P, Sampaio-Marques B. Effects of intermittent fasting on regulation of metabolic homeostasis: A systematic review and meta-analysis in health and metabolic-related disorders. J Clin Med Res. 2023 May 26;12(11).