The New Eating Strategy – Intermittent Fasting: Is It Right For You?

As the new year gets going, many of us have a renewed focus on our health - specifically diet and exercise. While some will opt for more tried-and-true goals of committing to regular gym sessions and limiting processed foods, others will look towards the latest health trends promoting weight loss such as intermittent fasting.

Intermittent fasting has become incredibly popular over the last five years, but many healthcare professionals are expressing concern about this eating strategy.

“Not all diets fit every individual,” says Hector Nazario, MD, Gastroenterologist and Chief of the Division of Hepatology at The Liver Institute at Methodist Dallas. “A person’s physical activity level, medical conditions and overall health are important factors contributing to whether or not a diet like intermittent fasting will be safe and effective for them.”

What is intermittent fasting?

Also known as “IF”, intermittent fasting isn’t a diet in the conventional sense, it is an eating pattern where you cycle between periods of fasting and eating. There are three commonly used and studied methods of IF. Daily time-restricted feeding is where a person eats during a specific window of time each day, typically using a 16:8 approach where they fast for 16 hours and eat during a 8 hour window every day. Periodic fasting or “5:2 fasting” is where a person will eat normally five days a week and fast two days a week. Alternate day fasting is simply fasting every other day, eating normally on the non-fasting day.

It’s important to note that the ‘eating’ done during the feeding days and times is supposed to be nutritious and well-rounded, think lots of fruits and veggies, fiber, healthy fats and proteins and avoiding or limiting processed foods, sugar and refined grains.

What are the health benefits of intermittent fasting?

The National Institute on Aging cites research which states “ hundreds of animal studies and scores of human clinical trials have shown that intermittent fasting can lead to improvements in health conditions such as obesity, diabetes, cardiovascular disease, cancers and neurological disorders.”

But how?

“When a person is fasting many things begin to happen in their bodies,” says Dr. Nazario. “Two of the most straightforward are their human growth hormone levels rise and insulin levels drop. Also, the body undergoes changes at a cellular level, which help with cell repair among other improvements linked to gene longevity and disease protection.”

Sounds pretty great right? Add in the fact that intermittent fasting participants tend to lose the same amount of weight as traditional diets, but has a reputation among supporters of being easier to stick with...it would seem as though there is finally a winning solution for weight loss!

Is intermittent fasting right for everyone?

Dr. Nazario says no. He is one of many physicians/healthcare experts reluctant to broadly endorse this eating strategy. As a specialist in gastroenterology (the branch of medicine dealing with the digestive system) his concern rests in the potentially harmful changes that fasting and binge eating can cause in the liver and digestive system.

He explains that changes in bowel habits (diarrhea, constipation, etc) is often the first clue that something might not be right.

“To be clear, this concern is for people who aren’t adhering to the ‘normal caloric intake’ during non-fasting times, but instead eating in excess,” says Dr. Nazario.

More and more frequently though, he is answering questions about intermittent fasting and liver disease.

Intermittent fasting and liver disease

Rising obesity rates have led to an increase in liver diseases - especially non-alcoholic fatty liver disease (NAFLD). “This disease is the buildup of extra fat in liver cells unrelated to alcohol consumption,” says Dr. Nazario.

To learn more about the progression of liver disease, click here.

“The very first conversation I have with an early stage fatty-liver patient is going to be about lifestyle modification, specifically diet and weight loss if they are obese,” says Dr. Nazario. “Because of the popularity of intermittent fasting as a weight loss tool, it comes up.”

While a recent study has shown that alternate day fasting appears more effective than other diets in controlling NAFLD, there is more to the story.

“Improving or stabilizing liver health is more than just simply losing weight which is why I hesitate to steer my patients towards intermittent fasting,” says Dr. Nazario. “Increasing fitness, avoiding alcohol, lowering cholesterol and triglycerides, controlling diabetes if present all play a role. There is just a lack of evidence still about IF and its effects on liver disease.”

About Dr. Nazario

Dr. Nazario specializes in the management of viral hepatitis, cholestatic and autoimmune liver diseases, complications of portal hypertension, cirrhosis, hepatocellular carcinoma, adult liver transplantation, medical complications after liver transplantation, and other gastrointestinal disorders.

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