The Record-Breaking Fast of Angus Barbieri
The most extensively documented and recognized instance of the longest fast belongs to Angus Barbieri, a Scottish man who went without solid food for an incredible 382 days between 1965 and 1966. At the start of his fast, Barbieri, then 27 years old, weighed 456 pounds (207 kg). Initially intended to last only a few weeks, the fast was extended under strict medical supervision from doctors at Maryfield Hospital in Dundee, Scotland.
Barbieri's daily intake consisted of calorie-free fluids, including tea, coffee, and sparkling water, supplemented with vitamins, electrolytes, and some yeast extract. He was an outpatient for most of the fast, visiting the hospital regularly for check-ups and blood tests. Astonishingly, he adapted so well to the prolonged lack of solid food that his desire to eat diminished over time.
By the end of his fast, Barbieri had reached his goal weight of 180 pounds (82 kg), having lost a staggering 276 pounds (125 kg). His first meal was a boiled egg with a slice of bread and butter, which he reported enjoying immensely. A follow-up study five years later, published in the Postgraduate Medical Journal in 1973, concluded that the prolonged fasting had no ill effects on his health, and he maintained a healthy weight. This remarkable case showcased the body's ability to use its substantial fat reserves for energy.
The Science Behind Prolonged Fasting
During a fast, the body undergoes a series of metabolic shifts to adapt to the absence of food. The first few days primarily involve depleting stored glucose (glycogen). Once these reserves are gone, the body enters a state of ketosis, burning stored fat for fuel instead. This metabolic conversion from glucose to fat for energy is a key reason Barbieri was able to sustain himself for so long, given his initial weight. However, this is an extreme biological response and carries significant risks, especially concerning nutrient deficiencies and refeeding syndrome, a potentially fatal complication that can occur when reintroducing food too quickly after prolonged starvation.
Why Guinness World Records No Longer Tracks This Category
While Barbieri's fast was recognized in the 1971 edition of The Guinness Book of Records, the organization later removed this category. They now refuse to publish records related to fasting due to serious safety concerns. This decision is a crucial reminder that Barbieri's success was a rare exception, and not the norm for extreme fasts. There have been documented cases of heart failure and even death in other patients attempting similar lengthy fasts under medical supervision, highlighting the extraordinary risks involved. Therefore, any form of extended fasting must be undertaken only with professional medical oversight and is not something to be attempted casually.
Comparison: Extreme Fasting vs. Intermittent Fasting
To better understand the scale and risks of Barbieri's record, it is helpful to compare his therapeutic prolonged fast with more common and medically accepted forms of intermittent fasting (IF). The table below outlines the key differences.
| Feature | Angus Barbieri's Prolonged Fast | Common Intermittent Fasting Methods |
|---|---|---|
| Duration | 382 days (over one year) | Typically 12-72 hours or specific time windows |
| Solid Food | None | Consumed during non-fasting windows |
| Supervision | Strict, continuous medical supervision | Generally self-managed for shorter fasts; medical advice recommended for longer ones |
| Goal | Therapeutic weight loss for a morbidly obese individual | Weight management, improved metabolic health, longevity |
| Nutrient Intake | Water, coffee, tea, and specific vitamin/electrolyte supplements | Food and beverages consumed during eating periods |
| Risks | High, including refeeding syndrome, heart complications | Generally low for short durations, but risks exist for certain individuals |
Conclusion
The 382-day fast completed by Angus Barbieri stands as the longest anyone has ever fasted and remains a powerful testament to human biological resilience under extraordinary circumstances. However, this feat was a medical anomaly, performed with constant professional oversight that is not replicable or advisable for the general public. Modern medical and safety guidelines emphasize caution, especially with extended fasting, due to the severe health risks involved, which is why Guinness World Records no longer sanctions such record attempts. For those interested in the health benefits of fasting, safe and controlled methods, such as intermittent fasting, are a far more prudent and medically sound approach that should always be discussed with a healthcare provider beforehand.
The case study of Angus Barbieri: Features of a successful therapeutic fast of 382 days' duration
Published in the Postgraduate Medical Journal, this is the original medical case report detailing Angus Barbieri's fast.
