Re: why does weight loss slow down after a week?

Hi Nutrifwd,

According to Dr. Shelton, metabolism slows about 25-40% over a long fast (i believe this means 30-40 days) and is back to normal within about 6 weeks. I have also read in another source that metabolism slows about 10% over 7 days and about 20% over 21 days. In any case, metabolism will decrease in a fast as the body is conserving its resources and will immediately begin it's return to normalcy once the fast is broken.

Weight loss slowing down as the fast continues has very little to do with metabolism... some, but very little. If we think about what a 10% reduction after 7 days means, if your bmr had been 2500 calories pre-fast, it would be about 2250 after 7 days of fasting. If we burned 250 fewer calories each day over 14 days it would only amount to one less pound burned (250 x 14 = 3500). With a 20% reduction it would amount to only 2 fewer pounds over 14 days.

In the above link, Dr. Shelton touched on the contents of the alimentary canal being emptied during the first week as a major factor and i was surprised... amazed actually... to see so little information about temporary water loss which to me is the most obvious source of large amounts of temporary loss, most of which takes place in the first week and most of which is restored in the first week of re-feeding.