Brad Feld

Tag: fasting

Today’s the last day of my ProLon Fasting Mimicking Diet. I wrote about my start in a post titled ProLon Day 1. I was a little nervous about trying this so I figured I’d blog about it to bust through any anxiety I was having about trying it.

I find myself very happy with it on Day 5. I’m not hungry and have only had a few stretches where I was hungry, and I think most of them were a result of someone (where 50% of the time that someone was Amy) saying “Are you hungry?” which then caused me to think about it.

The quantitative impact of it is pretty dramatic. My side by side weigh-in data (pre and post) is:

I generally only weigh myself once a week (usually on Saturday or Sunday morning). I don’t expect the weight loss to persist at the same level (e.g. I expect it’ll go back up a little when I start eating again). I haven’t run in the past five days (I took last week off) and am surprised that most of the weight that I lost was Skeletal Muscle Mass. And, it’s even more fascinating that my Body Fat Mass actually increased in the last week. I’m not really sure what to make of any of that, but my measurement in a week will be interesting.

If I was judging this only on weight loss, it would be a win. By seeing the type of weight I lost by doing the diet but not exercising, it feels like it wasn’t a win. But that’s perplexing to me so I’m interested in the next measurement a week from now.

But ProLon is about a number of other things besides just weight loss. I found their clinical trial data fascinating and their marketing summarizes it as:

Amy was right when she told me to get a bunch of blood work prior to starting ProLon and then do it again after I finished. I didn’t listen to her, which is usually a mistake on my part.

I’m going to try ProLon again in a month (they recommend you do it twice) and next time I’ll get my bloodwork done before and after.

In case you are wondering, my ultimate weight goal is 190. I’m 6’1″ and have a lot of lower body muscle mass from my running. It’s time to get down to 190 while working on both upper body muscle mass and flexibility.

I’m committed to that, although I’ve always had an extremely hard time with upper body exercise. If you’ve got any suggestions for a runner that hates going to the gym, loves to be alone, and has trouble getting into a weight lifting or yoga rhythm, I’m all ears.


As part of v53, I added the word “Healthy” into my statements of “what I want to be.” I’ve lost about 15 pounds this year, which has helped a huge amount with my running. I’m focused on losing another 10 pounds which will be me down to my goal weight of 195 that I’ll be happy maintaining for a while.

In addition to having an amazingly wonderful nutritionist named Katie Elliot who programs my meals, I’ve been experimenting with something different things. One that has been successful for me is intermittent fasting, where I only eat in an eight-hour window between 11 am and 8 pm.

This week’s experiment is ProLon, which is billed as a Fast-Mimicking Diet.

ProLon® is a 5-day dietary program that nourishes your body while promoting regenerative and rejuvenating changes, including effects on a wide range of markers that are associated with aging, such as cholesterol, inflammation, and fasting glucose.

ProLon® mitigates the burden and risks of water-only fasting, while responding to the unmet need of having a tasty, convenient, and safe dietary program.

Several people have mentioned it to me and one of the people in our office did it recently and loved how it made her feel. I’ve been pondering it but was pushed into trying it by a fascinating article about it in MIT Technology Review.

As a bonus, I have three dinners out in the next five days, so it’ll be good practice for not eating anything at dinner out, which is part of the intermittent fasting challenge (e.g. if I eat something at 11 am and have a dinner set that overlaps with 7 pm, I need to modulate what and how I eat at dinner out.)

I’ve decided not to run for the next five days. I’ve been running a lot lately and could use a mental reset so I figured timing it with ProLon made sense.

The experiment begins – now.