Is intermittent fasting heart-smart?

You exercise and eat right knowing heart disease is the leading cause of death in the U.S. But what if a healthy heart has more to do with when you eat rather than how many calories you consume?

A study in Endocrine Reviews suggests intermittent fasting may help prevent and manage heart disease.

Maedeh Ganji, MD, a board-certified cardiologist with Baptist Heart Specialists, said there are different intermittent fasting methods one can use based on their metabolic health, weight loss and personal schedules.

• 16/8 method: Fast for 6 hours with an 8-hour eating window.
• 5/2 method: Restrict caloric intake to 500-600 calories on two non-consecutive days.
• Alternate date fasting: Fast one day and eat normally the next.
• Eat and stop method: Fast for 24 hours once or twice a week.

“The benefits of these methods include improved insulin sensitivity, blood sugar control, cholesterol levels, and inflammatory markers that enhance cognitive function and help cellular repair within the body,” said Dr. Ganji. “It’s important to note that diabetic patients should only proceed with intermittent fasting under the supervision of their doctor.”

All you can eat

What about the buzz that you can eat what you want with intermittent fasting?

“The food you consume is the most important aspect and is at the forefront of intermittent fasting. Eating healthy means regularly having meals that include vegetables, fruits, complex carbohydrates and healthy fats while avoiding sugar and processed foods,” Dr. Ganji said. “Meal prepping can help alleviate poor food choices. Also, while grocery shopping, stay on the outskirts of the store where the fresh produce and vegetables are located.”

Backed by science

Intermittent fasting has often been viewed as a diet trend, but the eating method has been proven to help with cardiovascular wellness.

“Studies show us the markers that cause heart attacks and inflammation are significantly reduced during intermittent fasting. This eating method has also been shown to reduce blood pressure and cholesterol, increase insulin sensitivity, and reduce obesity and its various complications,” said Dr. Ganji. “This is important in prediabetic patients. During fasting, the body exhausts its sugar storage and starts burning stored fat. This is called metabolic switching.”

Dr. Ganji said studies have demonstrated positive outcomes for those with type 2 diabetes who are under a supervised intermittent fasting regimen. These include weight loss, reduced need for insulin and leptin, reduced insulin resistance, and increased levels of adiponectin, in some cases, even reversing the need for insulin.

However, it's important to discuss intermittent fasting with your doctor before trying it. There are certain conditions where it could be dangerous to fast for too long, Dr. Ganji said.

People who should avoid intermittent fasting include those who are:

• Pregnant
• Breastfeeding
• Underweight
• Have a history of eating disorders
• Diabetic (type 1 and type 2), though patients may proceed after discussing with their doctor
• Frail and elderly
• Under the age of 18

For those who have been cleared by their doctors, the best strategies to follow are:

• Begin with an 8-hour fast and increase to 12 hours if well tolerated
• Break your fast with warm liquids, lean protein and fiber
• Hydration is key; make sure to drink plenty of water

Note that long periods of fasting (greater than 24 hours) may be dangerous and will have the opposite effect, as it encourages the body to store more fat as a response to starvation.

Sticking to it

When it comes to intermittent fasting, remembering that it takes time for your body to get used to the new lifestyle will help you stick with it. It can take two to four weeks for the body to adjust, and you might feel hungry and cranky at the beginning. Research shows that those who make it through this adjustment period tend to stick with the new routine.

Strive to follow your intermittent fasting plan 80% of the time. If you want to go out socially to a family breakfast or dinner with friends, you can stray a little and then resume the time-restricted eating the rest of the week.

When followed correctly, intermittent fasting is a sustainable and beneficial method for long-term weight loss and cardiovascular health for those who can tolerate it and are medically cleared.