I remember well the pinnacle of my low carb diet experience — then more than 50 pounds weight reduced after 18 months of perfect adherence to the diet, staying in ketosis day after day after day. I ate less than 20 french fries in a year (I counted them out carefully, one by one — the exact total in 2012 was 13 french fries).

But I was really struggling then, at the end of this period, to take off that infamous “last 20” pounds.

And I was very tired.

In the summer of 2012, I had been sure I would be thin by Christmas. Then, of course, my life would be perfect. THIN AND CHRISTMAS – HOW FABULOUS! (what was I going to to do celebrate — eat salty snacks, Chex mix and fruit cake?)

I was at a normal weight by Christmas but not thin. Oh well, close enough. Hallelujah!  I had to look at myself in the mirror several times a day to absorb the change in the appearance of my body. People who hadn’t seen me in two years had to do a double take when they met me. People were afraid to ask about my weight in case I had cancer. What a grand success!

This momentous achievement happened over the holidays in 2012. Lying there on the couch, my dog-eared copy of Good Calories, Bad Calories sat next to me on the coffee table. I appreciated that it was Christmas time. No need to go to work.

And it was a very good thing I didn’t have to go to work. An inveterate, lifelong reader, I could no longer read a paragraph in a novel and understand it. My then flagging professional career required a good portion of the day be spent reading and writing.  Good luck with that. I was instead lying on the couch in the basement listening to a recorded book (Anna Karenina), trying to follow the story without losing the thread. That was next to impossible. I hadn’t yet heard the phrase “brain fog.” I could also barely leave the couch. Maybe just one more nap.

The entire second half of 2012 had become a write-off for me and the first half was bad. Fortunately, I had job that allowed me to just accept much lower pay for minimal work production; a 25 year work history at one place that meant they might look the other way at my terrible performance over a year or two.

I thought during that second half of the year “just lose that last 20 pounds and then re-focus on working again next year.” It hadn’t really occurred to me that the inability to read was just a wee bit of wrench in my future plans for work.

I couldn’t really connect the dots in my life at all anymore.

It didn’t really occur to me then that my waking at 4 am every morning in an anxious sweat, my withdrawal from social events, my brain fog, my inability to work, and my rapid pulse were related to my diet and weight loss. I hadn’t yet met other low carb casualties.

The pinnacle of my low carb experience was the nadir of my life.

It was my zealous adherence and belief that led to this. My belief in the theories spun in Good Calories, Bad Calories and the online social circle that believed in it, against any evidence to the contrary, that left me unable to work and barely able to sleep or get off the couch.

It took me a couple years to dig out of that hole.

Along the way, I lost many things and several close friends, but I did at least learn a few painful lessons.

The first lesson relates to the dangerousness of beautifully spun and elegant theories and their seductiveness.

Instead, pay attention to practical results that work. Distrust all theory. And all gurus. Especially the very smart ones.

Reading a single book can materially change your life — for both the better and the worse. Good Calories, Bad Calories was just such a book for me.