Intermittent fasting and weight loss: What you should know

Intermittent fasting (IF) has remained a time-tested tradition. The popular fasting method has consistently gained anecdotal and scientific evidence suggesting it improves health and even prolongs your life. However, many experts don’t want you fasting for two-thirds of your life.

Intermittent fasting is an eating pattern that limits your time for eating to a few hours during the day — claiming to have remarkable benefits for weight control, metabolic health, and aging.

• The basic idea is consuming calories only during a 6 to 8-hour window each day. This results in rapid weight loss (typically 8 to 10 percent from baseline) over short durations (8 to 12 weeks).

The most common IF methods include:

• 16:8 — fasting for 16 hours (including your sleep) and an 8-hour eating window
• 5:2 — consuming only 500-600 calories twice a week, eating normally the other five days
• Alternate-day fasting — fasting every other day
• Fasting for half the day (12 hours)

Dig deeper: Also known as time-restricted eating, IF was initially studied in mice for improvements in body weight, insulin resistance, blood pressure, and lipid profiles.

• Reaching peak popularity owing to social media buzz, intermittent fasting initially gained traction with Brad Pilon’s book Eat Stop Eat.
• Barring extreme examples, fasting has been shown to “supercharge” the immune system — achieved by suppressing inflammatory cytokines, increasing autophagy, and remodeling the gut microbiome.
• Studies have shown fasting to benefit conditions like COVID-19, heart disease, diabetes, cognitive decline, and certain cancers.

Many experts criticize intermittent fasting for being unsustainable in the long term, a lack of nutritional guidelines, connections to eating disorders, and even increasing the risk of some health conditions. However, popular figures have sworn by it.

• A year-long study found that time-restricted eating wasn’t any more effective than calorie restriction for weight loss.
• A study published in 2022 found that intermittent fasting was significantly associated with eating disorders, compulsive exercise, laxative use, and self-induced vomiting.
• Long-term intermittent fasting has also been linked with GI problems, sleep disturbances, and heart disease.

Intermittent fasting is a powerful weight loss tool in the short term. However, human studies exploring the long-term effects of time-restricted eating are insufficient — more notably questioning whether it serves as a break pedal for aging.