The 4-Hour Body_ An Uncommon Guide to Ra - Timothy Ferriss [60]
I would put in a new implant as soon as I landed in Managua.
Two Months Earlier—Firefly Restaurant, San Francisco
“Is this really interesting to you?”
It was a group dinner, and the man across from me thought I was just being polite. I’d asked what he did nine-to-five, and his answer was: medical device designer. In the span of “Oh, really?!” I was on him like a two-year-old Labrador on someone’s leg. The 20 questions were just getting started, and the wine hadn’t even arrived yet.
His cousin, a close friend of mine, chimed in, as I was already plotting experiments in my mind:
“Trust me. He’s interested. This is all he thinks about. It’s weird.”
And that is how I first heard the name “DexCom.” I jotted it down and did my best to act normal. It was hard to contain my excitement.
Soon thereafter, I knew all about DexCom. I called their headquarters, I called the head of marketing, I called the head of education, I spoke with the chief scientific officer, and I read about Charlie Kimball, over and over again.
Charlie Kimball is a type 1 diabetic. Unlike type 2 diabetics, he needs to inject insulin multiple times per day. He also happens to be a professional race car driver.
In 2006, Charlie became the first American to ever win an F3 Euroseries race. Then, in 2007, at age 22, he went to the doctor for a small skin irritation and left the office with a diagnosis of type 1 diabetes. Tragically, this meant he was forced to abandon racing altogether. Pricking your fingers to take blood sugar readings just isn’t possible when flying around curves at 150 miles per hour.
In 2008, Charlie returned to the wheel and claimed a podium finish in his first race. How?
He was the first race car driver in the world to have a strange device strapped to his steering wheel: the DexCom SEVEN continuous glucose monitor (CGM).
I check it like it’s one of my race car gauges as I’m driving around the track. It’s my body’s data. And it’s not information overload. It’s perfect.
In more tangible form, it’s a receiver that looks like this:
Charlie has an implant in his side (as I did) that samples his blood glucose levels22 every five seconds. These data are then transmitted to the receiver, a palm-sized device with a screen, where Charlie can see his blood glucose levels in a graph. It displays updates every five minutes, shows his ups and downs, tells him when he’s falling too fast, and alerts him when he’s at risk of hypoglycemia (low blood sugar).
So why on earth would I want to use this device as a nondiabetic? Why might you?
What if you could tell which meals were most likely to make you fat?
What if you could predict when food would hit your bloodstream and schedule exercise to optimize fat-loss or muscular gain?
What if, as an endurance athlete, you could eat carbs only when you most needed them instead of guessing with a timer?
The wish list went on and on. Now I just needed to check them off, one by one.
Making a (Wish) List … And Checking It Twice
After my dinner at Firefly, I immediately started jotting down dream tests, as this little gizmo seemed capable of clearing up some long- standing theoretical bullsh*t.
I’d long been fascinated by the glycemic index (GI) and glycemic load (GL) index, both of which reflect how much certain foods raise blood sugar levels as compared to a control (usually white bread or glucose with a designated value of 100). The higher the GI or GL value (the latter takes into account portion size),23 the more a food causes blood sugar to jump. The more a food causes blood sugar to jump, in general, the fatter you will get.
There are two problems with these indices. The first is that real- world meals seldom resemble laboratory meals. When’s the last time you ate 100 grams of potato starch by itself? Second, the indices are one- size- fits-all.
Reality isn’t one-size-fits-all. If someone of baguette-eating European descent eats white bread, will his blood response be the same as someone from a pastoral bloodline that historically fed off of livestock and little