Intermittent Fasting and Heart Health

Intermittent fasting and time-restricted eating have gained significant attention over the years for their potential health benefits. These dietary approaches have also been a part of culture and religious practices for ages.

However, a recent report from the American Heart Association suggests that intermittent fasting might have risks and impact the health of your heart. Ryan Daly, MD, an Indianapolis cardiologist with Franciscan Physician Network Indiana Heart Physicians, shared information on these new findings and the link between intermittent fasting and heart health.

What Is Intermittent Fasting?

Intermittent fasting is a dietary approach that alternates between periods of eating and not eating. It focuses not on the types of food consumed but on when you eat. Time-restricted eating focuses on eating within a limited number of hours during the day. On the other hand, intermittent fasting doesn’t distinguish between fasting during the day and fasting at night.

Intermittent fasting can involve sticking to a specific eating window each day or fasting on select days of the week. A few common methods of intermittent fasting include:

• The 16/8 method involves fasting for 16 hours each day and eating all your meals within a 8-hours.
• The 5:2 diet specifies regular food intake for five days of the week and restricted calories (about 500-600 per day) for the other two days.
• Eat-Stop-Eat involves a 24-hour fast once or twice a week, for example, not eating from dinner one day until dinner the next day.
• Alternate-day fasting alternates between days of normal eating and days of fasting.

People use intermittent fasting and time-restricted eating for weight loss. These techniques have potential benefits to improve metabolic health, increase longevity and improve heart health.

“While eating three meals a day works for some people, there’s evidence that eating earlier in the day can be better for our metabolism,” Dr. Daly said. “People who regularly eat breakfast also tend to have healthier body weights.”

Are There Cardiovascular Benefits To Intermittent Fasting?

Intermittent fasting has gained attention for its potential weight loss benefits and positive impact on cardiovascular health. Intermittent fasting has several benefits for your heart, including:

Improves cholesterol levels

Unfortunately, Americans eat all day, sometimes 14 hours a day.

“Studies found that when we decreased that eating window to eight to 10 hours a day, patients lost weight and improved their overall cardiovascular metabolic profile,” said Dr. Daly. “They also lowered their LDL cholesterol levels – their bad cholesterol.”

Supports healthy weight loss

Weight management is directly beneficial for reducing the risk of heart disease.

“If you’re not at a healthy weight and take high blood pressure medicines, a 10-pound weight loss reduces blood pressure by about five points,” said Dr. Daly. “That’s the typical amount of blood pressure reduction from one blood pressure pill. We also know for someone experiencing medical obesity, every seven pounds of weight loss reduces the risk of heart failure by 11 percent.”

Weight loss is a fantastic way to reduce your risk of stroke, heart attack and cardiovascular death, he said.

Improves metabolism

When you limit the time when you eat, it regulates your metabolic processes and potentially leads to lower insulin levels. Insulin is the hormone responsible for transporting glucose (blood sugar) from the bloodstream into cells, where it’s used for energy. When you fast, insulin levels drop, which helps you burn fat and reduces your blood sugar levels.

“I think, in America, we’ve lost some of the natural signals of hunger,” Dr. Daly said.

Without these signals, people don’t only eat when they’re hungry and don’t stop eating when they’re full.

“We’re also taught to eat three times a day, which might be OK for some people but not everyone,” he said.

Some data support the idea that a healthy meal earlier in the day helps with a person’s metabolic health.

What Are The Potential Risks And Recent Concerns With Intermittent Fasting?

Despite the benefits, the American Heart Association recently highlighted research showing a 91 percent higher risk of cardiovascular death associated with 8-hour time-restricted eating.

Dr. Daly said it’s important to examine these recent findings on fasting carefully.

“The abstract was not peer-reviewed or published in a medical journal,” he pointed out. “It wasn’t a clinical trial but a retrospective analysis based on food recall data.

“In a retrospective study, you can only say that X may be associated with Y. You can’t say X caused Y. Watching TV may be associated with an increase in cardiovascular events. But is it the TV watching or the sedentary lifestyle that caused the cardiovascular event? Is it possible that you will still have an event if you only watch TV while on a treadmill? Or is it the fact that they’re sedentary?”

People must be careful not to draw inaccurate conclusions from the data.

5 Tips For Safe Intermittent Fasting

If you’re considering intermittent fasting for weight loss, Dr. Daly recommended working with your healthcare provider, starting gradually and prioritizing hydration. A slow start allows the body to adjust to the fasting schedule, manage chronic conditions and your body’s response to medications without food, and helps reduce the risk of potential side effects including dizziness, fatigue or irritability.

Gradually extend fasting periods over time to better gauge your body’s response and make adjustments along the way, and keep your healthcare provider informed of any side effects or medical concerns.

These five tips can help you get started on intermittent fasting safely:

With an extended fast, your blood pressure will naturally decrease within the first few days. As you burn fat and your insulin levels go down, your body will lose water and salt.

“We see this a lot, especially in people transitioning from a high-processed food diet to a relatively lower-carb diet,” Dr. Daly said.

A fast can jump-start your weight loss process, but you and your health provider need to decide if one of the common intermittent fasting methods makes sense for you and your health.

Before you begin intermittent fasting, it’s important to get professional medical guidance. Talk to your primary care provider to create the best plan for you. If you have questions about your family’s nutrition or the best nutrition for weight loss or overall health, make an appointment to talk with a Franciscan Health dietitian or nutritionist.