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by PeterWhittaker 3982 days ago
Not to mention that the article confounds calories, a physical unit of energy, Calories, a unit of nutritional energy, and kilojoules, the preferred physical unit of energy.

At one point, it indicates that 3,500 calories corresponds to a pound of body weight, then later indicates this came from research suggesting that 3,500 kJ corresponds to a pound of body weight and that this is where the 3,500 calories figure comes from.

Problem is, 3,500 kJ = 836 520.076 calories = 836.520076 Calories. So which is it? 3,500 kJ per pound of body weight, 3,500 Calories, or 837 Calories, or something else?

FYI: A nutritional Calorie is actually a kilocalorie (1,000 calories). One Calorie = 4.184 kJ.

1 comments

According to the Hacker's Diet [1], 3.500 Calories is equivalent to a pound.

[1] Admittedly poor reference, but in tone with the Hacker News. Also, the author most probably sources from the same reference the article does for the traditional conversion and I trust him to not mess up with units.

Hmm, OK. Doesn't explain how the "3,500 kJ per pound" got in there - perhaps I still have optimistically high expectations, but I would have hoped that somewhere along the line the author or their editor would have noted that a pound cannot be equivalent to both 3.5 Mcal and 3.5 MJ. But mayhaps I wax pedantic.
You're right, I was also very surprised by this error and have commented on it as soon as this was posted. I just wanted to elucidate the correct value.