Several articles have been written about it, celebrities and a few of your friends swear by it. But questions and concerns remain about the efficacy and safety of intermittent fasting or IF.
To help the uninitiated and those curious to try IF, a health professional from Makati Medical Center gives the lowdown on Hugh Jackman and Jennifer Aniston’s diet plan.
What it means
According to Maricar M. Esculto, RND, MD, IF is not an eating pattern by definition. “An eating pattern is defined as a combination of different foods or food groups. As its name suggests, intermittent fasting is more of alternating eating and abstaining from food.”
“It is a way of eating that focuses more on ‘when’ than on ‘what’ you eat,” she explains, adding that such a practice is not new, citing various religions, including Catholicism and Islam, that observe fasting at specific times of the year.
Further, this pattern has been present years before when prehistoric ancestors who hunted for their food did not eat until they caught their next meal.
How to do it
“There are different ways to do intermittent fasting,” adds Dr. Esculto. “The most popular and simplest is 16/8 or fasting for 16 hours and eating within eight hours.”
She continues, “For example, you can eat from 1:00 p.m. to 9:00 p.m. then abstain from eating from 9:01 p.m. to 12:59 p.m. In Eat-Stop-Eat, fasting lasts for 24 hours. In other words, one can skip dinner and abstain from eating until dinner the next day. In the 5:2 diet, you spend two days in a week eating no more than 500 calories a day.”
Water, tea, and black coffee are allowed during the period of fasting.
To put simply how it works: eating for a certain period naturally limits the person’s caloric intake.
“It lowers the insulin level in the blood and if the person has no intake of food for a prolonged period of time, fat will be mobilized to supply the body’s energy needs,” says Dr. Esculto.
But just because the focus of IF is the time of eating not what a person eats, dieters who think they can eat all they want during IF’s eating phase will be disappointed, says Dr. Esculto.
“It’s still all about eating sensibly, avoiding high-calorie foods, and practicing portion control. If you binge-eat after your fast, then you are sabotaging your weight-loss goals.”
Advantages and disadvantages
Aside from the desired weight loss (case in point: talk show host Jimmy Kimmel shed 25 lbs. in 2015 via IF), the eating/fasting pattern has also been credited for reducing inflammation, decreasing Low-Density Lipoproteins (LDL) or “bad” cholesterol and triglycerides, and lowering the risk of cancer and heart disease.
“IF has been credited for triggering the increase of the brain hormone BDNF (brain-derived neurotrophic factor) and protecting individuals against Alzheimer’s disease, however, this was observed among animal models so far,” points out Dr. Esculto.
While it sounds too good to be true IF comes with a few caveats.
According to Dr. Esculto, “Hunger is the chief complaint of those on intermittent fasting, especially if they’re just starting. People initially feel weak and not as mentally sharp, too.”
Experts have also discovered that depriving yourself of food for some time increases the body’s level of cortisol, otherwise known as the stress hormone.
Moreover, IF isn’t for everyone—particularly women who are pregnant, breastfeeding or trying to conceive, as well as individuals with diabetes, low blood pressure, a heart condition, history of eating disorders, and other pre-existing conditions.
“It is strongly recommended to consult with your physician before trying this way of eating,” advises Dr. Esculto.
The verdict
While intermittent fasting has been used as a safe way to initiate weight loss or break a weight-loss plateau, doctors do not recommend it be practiced long-term.
“I would rather people develop a healthy attitude towards food and eating,” asserts Dr. Esculto. “Eat fresh fruits and vegetables and high-quality protein. Eliminate processed and junk foods. Exercise regularly.”
