I find this subject really interesting and when I did Atkins and later Lighter Life, this was something I researched a lot, i was told it was a side effect of ketosis. At the time it was considered that as you reduced carbs the body used fat stores to create ketones as an alternative energy source, thus the body went onto defence mode and stopped or slowed down doing things it considered not necessary, like growing hair, nails, and sometimes new skin. With all these things the bits you see are usually the dead bits. More recent studies believe that as part of the bodies defence mechanism the thyroid tries to fight the acetones produced by the keytones. And one of the side affects of thyroid problems is hair loss. The thyroid can be supported by iodine which is found in sea kelp. Sorry if this is boring, I'm a bit of a nerd when it comes to things like this.
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