Considerations When Trying Intermittent Fasting

Intermittent fasting should be done based on each person's physical condition. Photo: Illustration

But behind the alluring facade of a “miracle diet,” how much is science and how much is fantasy?

What to eat, when?

Intermittent fasting is not a new diet. It is an eating method that cycles between eating times and fasting times. Rather than focusing on a menu, IF changes eating habits to match your biological clock – which is believed to optimize metabolism, control weight, and improve health.

There are many popular IF styles today such as: - 16/8: Fast for 16 hours, eat during the remaining 8 hours of the day; 5:2: Fast strictly only 2 days per week; Eat-Stop-Eat: Fast for 24 hours, one to two times per week; - OMAD (One Meal A Day): Eat only one meal per day within 1-2 hours; Warrior Diet: Eat light during the day, large main meal in the evening; - ADF (Alternate-Day Fasting): Eat every other day alternating between normal eating and fasting.

A 2022 study from Wake Forest School of Medicine and Virginia Tech looked at the effects of IF in the context of the global “obesity epidemic.”

Intermittent fasting has been shown to promote the conversion of fatty acids into ketones — an alternative energy source when the body runs out of glycogen.

Ketones help maintain brain and muscle energy, while also supporting weight loss, improving blood pressure and lipid disorders. Also in 2023, Jeddah University (Saudi Arabia) surveyed a group of Muslims who practiced intermittent fasting during and after Ramadan.

Of the 147 participants, 85% reported weight loss - most between 1-5 kg, a few over 10 kg. However, side effects were not uncommon: headaches, dizziness, mood swings and sleep disturbances.

Previous studies have also partly reinforced the potential benefits of IF. For example, Trepanowski's (2017) study found that intermittent fasting is as effective at weight loss as continuous dieting; or IF can improve blood pressure, cholesterol - reducing cardiovascular risk (Tinsley's (2016) study).

In 2018, Mattson conducted research that IF has positive neurological effects - stimulating new brain cells, reducing the risk of Alzheimer's or possibly supporting blood sugar control in people with prediabetes or type 2 diabetes.

One of the benefits of IF that is often mentioned but few people understand is the mechanism of cell self-eating (Autophagy). Simply put, when “starved”, cells will self-digest and recycle defective or excess components – helping to rejuvenate and cleanse internal organs.

Work on this mechanism won Japanese scientist Yoshinori Ohsumi the 2016 Nobel Prize in Medicine. While fascinating in theory, the reality is more complicated.

Animal studies show that Autophagy is only activated after 24-48 hours of fasting—a time period that far exceeds most common types of IF. And in humans? There’s no solid evidence to confirm exactly when Autophagy kicks in.

There are advantages and disadvantages - choose the right one

But IF isn't for everyone. Like any health intervention, intermittent fasting isn't a “one size fits all” solution.

According to nutritionists, people with underlying conditions such as diabetes, low blood pressure, eating disorders, pregnant or breastfeeding women should not try IF on their own. Common side effects include: fatigue, irritability, digestive disorders, loss of concentration.

In addition, there is a worrying fact: many people approach IF not through medical advice, but from... TikTok or word of mouth. Many people fast extremely, skip meals for long periods but compensate with meals rich in empty calories - leading to nutritional imbalance, muscle loss, and physical weakness.

If understood and applied correctly, IF can be an effective tool to support weight loss, improve cardiovascular health, slow aging and enhance cognition. But if you blindly follow the trend and ignore personal factors - from physical condition, physiology to pathology - the benefits do not outweigh the harm.

Ideally, start with the advice of a doctor or nutritionist. Build a reasonable fasting schedule that fits your biological rhythm and schedule. In particular, when applying IF, it is still necessary to ensure healthy eating principles: food variety, enough vitamins and minerals, control starch and bad fats.

Take your health seriously. IF is not a magic wand. It does not replace sleep, exercise, or a healthy mindset. There is no “miracle diet” that will make you healthy if you don’t really understand your body.

Beware of online “preaching”. What you need is not a quick weight loss, but a sustainable lifestyle – where eating, sleeping, resting and exercising together help you live a long, healthy and quality life.

Source: https://baoquangnam.vn/can-nhac-khi-thuc-hien-nhin-an-gian-doan-3153199.html