Mixed
Periodic fasting (4-21 days) with 200-250 kcal/day intake is safe, well-tolerated, and improves cardiovascular risk factors and well-being in a large observational cohort.
If you are healthy and want to try a prolonged fast, start with a shorter duration (4-5 days) and ensure you have medical supervision. The Buchinger method involves consuming very few calories (200-250) from plant-based sources, drinking plenty of water, and engaging in light activity. Expect weight loss and improved blood markers, but be aware that hunger and mild symptoms are common in the first few days.
The results from 1422 subjects showed for the first time that Buchinger periodic fasting lasting from 4 to 21 days is safe and well tolerated. It led to enhancement of emotional and physical well-being and improvements in relevant cardiovascular and general risk factors, as well as subjective health complaints.
Why this rating
Large observational study (n=1422) but lacks a control group and has potential selection bias (volunteers from a specialized clinic).
Source
Safety, health improvement and well-being during a 4 to 21-day fasting period in an observational study including 1422 subjects
Françoise Wilhelmi de Toledo et al. · PLoS ONE · 2019
DOI 10.1371/journal.pone.0209353
Related findings · Mixed
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