David Blaine has subjected himself to a prolonged fasting experiment lasting between Sept. 5 and Oct. 19, 2003.
“A 30-year-old male, weight 96 kg, height 1.84 m, entered a transparent Perspex box on the banks of the river Thames in London and was suspended in the air from a crane for 44 days. During this period, he took only water to drink.” 
At the end of the fast, Blaine had lost 24.5 kg and ~8 BMI points (29 => 21.6). Though his BMI was not life-threatening, he was admitted to the hospital for intensive and careful refeeding, as some of his biomarkers were out of normal limits. 
Several research studies have been published based on Blaine’s self experiment. Let’s see some data…
David Blaine’s 44-day Fast
In terms of body composition progression [2, 3]:
“Total energy expenditure was estimated to be 1638–2155 kcal/d of which 13.0–17.1% was from protein oxidation.” 
They used three methods to estimate energy expenditure (TEE).
– method 1: 1638 kcals/day
– method 2: 2155 kcals/day
– method 3: 1736 kcals/day
Average BMR (basal metabolic rate) was estimated at 1578 kcals/day. For precise details see study .
It would have been great if rather than estimating, they would have measured his BMR and TEE. Similarly, they used skin fold measurements to estimate his body comp. changes, which is also inaccurate by modern means.
Blaine’s muscle mass loss was 10.4 kg, estimated from creatinine excretion. 
Urine volume was above 3 liter (3L) per day. Daily urine tests measured: glucose, ketones, pH, nitrite, pH, bilirubin, and a few other markers. 
“Total N loss during the entire 44-d period was calculated from cumulative urine N loss plus fecal N loss (assumed to be 6 g of N during the fast, resulting from four bowel actions) and other miscellaneous losses including those from skin (assumed to be 5 mg of N/kg of lean body mass per day during fast).” 
As Jackson et al. (2006) describe:
“DB, who was initially a muscular looking man, was visibly thinner on exit from the box. His blood pressure taken almost immediately before the event began was 140/90 mmHg while lying and 130/80 mmHg while standing, and at the end it was 109/74 mmHg while lying (pulse 89 beats/min) and 109/65 mmHg while standing (pulse 119 beats/min).” 
As his experiment went on, Blaine felt weaker. Two weeks in and onward he experienced faintness and dizziness upon standing up quickly, which is often reported by people who fast for long periods of time.
“He also developed transient sharp shooting pains in his limbs and trunk, abdominal discomfort, nausea, and some irregular heart beats.” 
Here’s a picture of some biomarkers at the end of the fast – day 0 of refeeding :
And here’s a bigger overview :
Blaine went into a hypocaloric refeed for the first three days. They used a liquid formulation called Ensure Plus (220 ml/carton), which delivered:
330 kcals: 44.4g carbs (12.7g sugar), 10.8g fat, 13.8g protein
It also contained: 11.5 mmol Na, 11.3 mmol K, 6.4 mmol Ca, 6.5 mmol PO4, 2.7 mmol Mg
The refeeding strategy was as follows :
Day 0: Overnight, 2 cartons + water (ad lib.)
Day 1: 2 cartons + water (ad lib.)
Day 2: 5 cartons + water (ad lib.)
Day 3: 6 cartons + water (ad lib.)
Day 4: light diet of 1,500 kcals
Day 5: ad lib.
Even though Blaine was keen to eat immediately after getting out of the box, he understood that he has to go through the careful refeeding strategy. From Blaine’s diary :
Day 1: experienced cramps and “was not yet ready to eat but the thought of chewing and tasting again was so strong”.
Day 2: continued experienced cramps, started craving food
Day 3: “I could not help it; I wasn’t hungry but just wanted to eat once again”.
That’s interesting. Am I missing something? Craving != hungry ?
Day 5: “my hunger grew out of proportion and I was eating almost a double portion of all meals”.
As per the researchers: “the high 3-hydroxybutyrate concentration measured could contribute to low appetite on the first few days.” 
Some out of range biomarkers at the end of the fast :
– slightly low K – 3.3 mmol/L
– high B12
– high Zn
– abnormal liver function
– high IGFBP1
– high GH
– low-normal insulin
– very low IGF1
– high cortisol
– low leptin and ghrelin
PYY, AgRP, Alpha-MSH, NPY, and POMC (hunger markers) – not substantially different from those measured in subjects after overnight fasting.
“Blaine’s sensation of hunger, which he did not have during the first few days, increased considerably on day 3; this increase had been immediately preceded by an elevation in plasma levels of orexin A and resistin, an observation of unclear relevance, given the available data.” 
Some of his nutritional and metabolic deficiencies required supplementation in the following manner :
– 50 mg thiamine twice/day
– 80 mg niacin
– 8 mg vitamin B6
– 8 mg vitamin B2 and 20 mg vitamin B1 daily
– 5 mg folic acid/day
– Forceval capsules (vitamins and trace elements), 1 capsule twice/day
– 24 mmol effervescent KCl 3 times/day for 2 days and then 12 mmol 3 times/day
Data should speak for itself. My additional comments are not necessary. David Blaine is no stranger to outstanding experiments of will. And since we’re dealing with data from his n=1, it would be appropriate to let him do the ending:
“I think to be able to survive something like this proves that we can live with nothing…Everybody wants domination, wants to own and control everything and believes that money and diamonds and riches and all this stuff is what life is about, but, you know, at the end of the day that really means nothing…there is no value in that.” [*]
- Korbonits, M., Blaine, D., Elia, M., & Powell-Tuck, J. (2005). Refeeding David Blaine—studies after a 44-day fast. New England Journal of Medicine, 353(21), 2306-2307.
- Korbonits, M., Blaine, D., Elia, M., & Powell-Tuck, J. (2007). Metabolic and hormonal changes during the refeeding period of prolonged fasting. European Journal of Endocrinology, 157(2), 157-166.
- Jackson, J. M., Blaine, D., Powell-Tuck, J., Korbonits, M., Carey, A., & Elia, M. (2006). Macro-and micronutrient losses and nutritional status resulting from 44 days of total fasting in a non-obese man. Nutrition, 22(9), 889-897.
Images: here, here, and here