New research from the American Heart Association challenges popular diet’s safety, prompting urgent warnings from medical experts.
A groundbreaking study presented by the American Heart Association has sent shockwaves through the health and wellness community, revealing that the widely popular 168 intermittent fasting method—where individuals fast for 16 hours and eat within an 8-hour window—may increase the risk of cardiovascular death by a staggering 91 percent. The research, which analyzed dietary patterns and mortality data from over 20,000 American adults, directly contradicts previous assumptions about the long-term safety of time-restricted eating.
Understanding the 168 Intermittent Fasting Method
Also known as intermittent fasting, the 168 diet has gained immense popularity as a weight loss strategy. The concept is straightforward: individuals abstain from calorie-containing foods and beverages for 16 consecutive hours each day, consuming all meals within an 8-hour eating window. During the fasting period, only water, unsweetened black coffee, and plain tea are permitted.
The underlying mechanism relies on depleting the body’s glycogen stores—carbohydrates stored in the liver and muscles. Once these reserves are exhausted, the body shifts to burning fat for energy, producing ketones and theoretically promoting weight loss and reduced body fat.
The Research That Changed Everything
Led by Dr. Wen Ze, professor and chair of epidemiology and biostatistics at Shanghai Jiao Tong University School of Medicine, the study examined data from the National Health and Nutrition Examination Survey (NHANES) spanning 2003 to 2018. Researchers cross-referenced participants’ eating patterns with mortality records from the U.S. Centers for Disease Control and Prevention through December 2019.
The findings were stark:
- People who consumed all food within less than 8 hours daily faced a 91% higher risk of dying from cardiovascular disease
- Individuals with pre-existing heart disease or cancer also showed elevated cardiovascular death risks
- Among those with cardiovascular conditions, eating within an 8-to-10-hour window was linked to a 66% increased risk of death from heart disease or stroke
- Time-restricted eating did not reduce overall death risk from any cause
- Interestingly, cancer patients who ate for more than 16 hours daily showed a reduced cancer mortality risk
Dr. Wen Ze cautioned that while 168 fasting may offer short-term benefits for weight loss, its long-term implications are concerning. “Compared to the typical 12-to-16-hour eating range, shorter eating windows were not associated with living longer,” he stated.
Who Should Avoid 168 Fasting?
Medical professionals have identified three groups who should steer clear of this eating pattern:
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Individuals with high energy demands – Athletes, manual laborers, and those with physically demanding jobs risk hypoglycemia and fainting during prolonged fasting periods.
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Poorly controlled diabetics – Blood sugar fluctuations become more dangerous when meal timing is restricted, increasing the risk of dangerous low-blood-sugar episodes.
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Those prone to binge eating – Compressing calories into an 8-hour window can lead to consuming two to three times the normal portion size, negating any potential benefits and potentially causing weight gain or gastric issues.
Real-World Consequences
Previous case reports have documented adverse effects from 168 fasting. A Taiwanese physician shared a case of a man who developed gastric ulcers and inflammation after just three months on the diet, attributing the damage to poor eating habits during the eating window.
The Bottom Line
While 168 intermittent fasting remains a trendy weight loss tool, this landmark study raises serious red flags. Nutrition experts now recommend consulting healthcare providers before adopting any time-restricted eating plan, especially for those with existing health conditions. The takeaway is clear: what works for short-term weight management may carry hidden long-term risks that far outweigh temporary benefits.
For those considering intermittent fasting, medical professionals suggest exploring less restrictive approaches, such as the 12:12 method, and maintaining balanced nutrition regardless of meal timing. As always, sustainable weight management relies on whole foods, portion control, and regular physical activity—not extreme dietary constraints.
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