Intermittent fasting, which involves alternating cycles of eating and going without food, recently made splashy headlines around the world. During the recent American Heart Association conference, intermittent fasting was associated with a 91 percent increase in risk of cardiovascular disease.

The study involved over 20,000 American adults who limited their eating across less than eight hours per day. These people were found to be “more likely to die from cardiovascular disease compared to people who ate across 12 to 16 hours per day.”

“Time-restricted eating, a type of intermittent fasting, involves limiting the hours for eating to a specific number of hours each day, which may range from a four to 12-hour time window in 24 hours,” explained the press release from AHA.

Most people who adopt a time-restricted eating diet follow a 16:8 eating schedule, where they eat all their foods in an eight hour window and fast for the remaining 16 hours each day, the researchers noted.

The said findings created quite a stir as previous research has found that time-restricted eating improves several cardiometabolic health measures, such as blood pressure, blood glucose and cholesterol levels.

People should not be alarmed by it, said Julia Zumpano, a preventive cardiology nutritionist at Cleveland Clinic. To start with, the research was presented in an abstract rather than as a full study. More importantly, it has not yet been published in a peer-reviewed journal.

“It’s basically a one-sheet page describing what they wanted to do,” Zumpano, a registered dietitian, was quoted as saying by GQ. “So, it’s kind of like looking at the front of a food label without being able to look at the back. You don’t know the nutrition facts or have the ingredients – you’re just looking at the marketing on the front.”

Dr. Christopher Labos, a cardiologist with a degree in epidemiology, went as far as “selectively” ignoring the findings. As he explained in a commentary that was published by Medscape: “The study was, by nature, observational and therefore prone to confounding.”

Researchers, he said, adjusted for relevant variables, “but as we have learned multiple times in the past, residual confounding is always a potential issue. Also, researchers didn’t have information on the quality of the study participants’ diet. If someone breaks their 16-hour fast with ultra-processed junk food, the type of food might be more relevant to long-term cardiovascular health than when it was eaten.”

According to Dr. Labos, people may have engaged in intermittent fasting because they had shift work or an irregular sleep schedule, which are independent cardiovascular risk factors.

“It’s also possible that people adopted time-restricted eating as a dietary strategy precisely because they were at high risk for cardiovascular disease, an association that could be explained by reverse causation,” he pointed out. “Suffice it to say, many other external factors might be at play here.”

Traditional Fasting

“I assert that fasting is the most efficient means for correcting any disease,” said Dr. Adolph Mayer, the first psychiatrist-in-chief of the Johns Hopkins Hospital.

Most religions, however, use periods of fasting as a means of demonstrating faith or penitence, and an opportunity for spiritual reflection. Fasting has also historically been a means to express political views and a form of protest.

In the Christian context, fasting is simply abstaining from food for spiritual reasons. At times, fasting means abstinence from drinking liquids as well – a total fast for a brief period.

But intermittent fasting is a different story. It is actually a dietary approach where you are not allowed to eat for some period of time. “The precise period of time depends on the type of intermittent fasting you’re doing,” Zumpano said.

Intermittent Fasting

“There are several different ways of doing intermittent fasting, all of which involve splitting the day or week into eating and fasting periods,” explained Kris Gunnars, who has a bachelor’s degree in medicine. “During the fasting periods, you eat either very little or nothing at all.”

Gunnars writes for the website, www.healthline.com. In his article, he cites the following as most popular methods:

The 16/8 method: This involves skipping breakfast and restricting your daily eating period to eight hours, such as 1:00 to 9:00 p.m. Then you fast for 16 hours in between.

Eat-Stop-Eat: This involves fasting for 24 hours, once or twice a week, for example by not eating from dinner one day until dinner the next day.

The 5:2 diet: With this method, you consume only 500 to 600 calories on two non-consecutive days of the week but eat normally the other five days.

“Many people find the 16/8 method to be the simplest, most sustainable, and easiest to stick to. It’s also the most popular,” Gunnars wrote.

No Three Meals A day

Most Filipinos usually eat three times a day (breakfast, lunch, and dinner) plus merienda in between those meals. “Intermittent fasting contrasts with the normal eating pattern,” says Dr. Mark Mattson, neuroscientist at Johns Hopkins Medicine. “If someone is eating three meals a day, plus snacks, and they’re not exercising, then every time they eat, they’re running on those calories and not burning their fat stores.”

Dr. Mattson cautions that longer periods without food – like fasting for 24 hours or more – are actually dangerous. Doing fasting for a day or two without eating actually encourages the body to start storing more fat in response to starvation.

In his research, Dr. Mattson found out that the body becomes accustomed to intermittent fasting two to four weeks after. “You might feel hungry or irritable while you’re getting used to the new routine,” he says, adding that people who make it through the adjustment period tend to stick with the plan because they notice they feel better.

Weight Loss
By reducing your calorie intake, all of these methods should cause weight loss. “By making you eat fewer meals, intermittent fasting can lead to an automatic reduction in calorie intake,” Gunnars wrote. “Additionally, intermittent fasting changes hormone levels to facilitate weight loss.”

Studies show that intermittent fasting can be a very powerful weight loss tool. In 2014, a review study found that this eating pattern can cause three to eight percent weight loss over three to 24 weeks, which is a significant amount, compared to most weight loss studies.

Another study, done in 2011, showed that intermittent fasting causes less muscle loss than the more standard method of continuous calorie restriction.

“However, keep in mind that the main reason for its success is that intermittent fasting helps you eat fewer calories overall,” Gunnars wrote. “If you binge and eat massive amounts during your eating periods, you may not lose any weight at all.”

Type 2 Diabetes 

Intermittent fasting may also have benefits for diabetes prevention as it can reduce insulin resistance, which is a major feature of type 2 diabetes. This is according to Aaron Kandola and Mandy French, authors of a feature which was published in Medical News Today.

“A 2022 review on intermittent fasting and metabolic health showed that intermittent fasting can reduce insulin resistance. It states that this could be due to reduced energy, or calorie, intake can lead to decreased insulin production,” the two wrote. However, more research is needed on larger controlled trials.

A previous study, which was reported in 2017, also showed that intermittent fasting may be more effective for regulating blood sugar in males than in females. The study showed that after three weeks of intermittent fasting, blood sugar regulation in the female participants worsened, whereas in males, it improved.

Other Benefits

Meanwhile, the Mayo Clinic says some research suggests that intermittent fasting may be more beneficial than other diets for reducing inflammation and improving conditions associated with inflammation, such as: Alzheimer’s disease, arthritis, asthma, multiple sclerosis, and stroke.

Gunnars, in another article which he co-wrote with Mike Hoskins, also pointed out that intermittent fasting can also help you live longer. They cited some studies which show that it may extend one’s life “as effectively as calorie restriction.”

Gunnars, in another article which he co-wrote with Mike Hoskins, also pointed out that intermittent fasting can also help you live longer. They cited some studies which show that it may extend one’s life “as effectively as calorie restriction.”

There was a 2021 clinical research which claimed that even mild intermittent fasting – along with healthy nutrition, movement, sleep patterns, and stress management – could help people live longer (decrease their biological age, per the study) by a little more than three years.

Not For Everyone

“Intermittent fasting is safe for many people, but it’s not for everyone,” said Mayo Clinic’s Dr. Manpreet Mundi. “Skipping meals may not be the best way to manage your weight if you’re pregnant or breast-feeding. If you have kidney stones, diabetes, gastroesophageal reflux, or other medical problems, talk with your doctor before starting intermittent fasting.”