Whereas to the naked eye this appears entirely related to the subject matter of this blog, this story is, I suppose, an engineering story at it’s heart. Starting in early 2019, I noticed that I had a bit of a problem. Sitting on my hind end all day typing and talking was catching up with me, weight-wise. I was gaining weight and none of the half-hearted measures I had taken up to that point was having any effect. I was quite afraid of gaining 2-5 pounds a year for the rest of my life, eventually accumulating a list of chronic ailments and lost abilities and the pills that typically go along with them. What was I going to do?
I started eating my token breakfast (just a high-protein yogurt or an orange) later and later into the day. I remember being proud of myself when I could get to 9am, then 10am, then 11am before eating. Over a period of just about two weeks, I was able to make this adjustment, and my weight started dropping. Around this time I saw some content about intermittent fasting and it began to make sense that this was a real thing and could be healthy. Growing up in the 90’s, I was basically under the impression that if I went more than 2 hours without a muffin (or other low-fat food of my choice) that my body would start harvesting heart and diaphragm muscle for energy.
So, upon learning that it was formally a practice to limit eating to 8 hours or less in a 24 hour period, I was off to the races. I lost 10 pounds a month for 3 months in a row before consciously eating a bit more during my eating window because I became afraid that this was causing my hair to fall out. But, the practice has continued from August of 2019 to this day. I think in a given year, there may be something like 10 days in which I eat outside of an 8 hour window. This practice of intermittent fasting has been a great step forward in my life and I wanted to review here how it has impacted the objective measures of my health. The human body is an amazing system and it’s very easy to go down the rabbit hole of what is cholesterol and what do various measurements of it mean for predicting if good or bad things are happening inside of us. Let’s check out some data!
Lipid Profiles
Going forward I am going to make an effort to get a NMR lipid profile done, but the historical data that I have is limited to the run-of-the-mill cholesterol and triglyceride numbers, so that’s what we’re looking at in the figures below. On these graphs, there are two significant demarcations of behaviors that I have begun: the intermittent fasting mentioned above, and in 2022 I began using an e-bike as a source of transportation whenever possible. What it amounts to is that I have e-biked 80 miles per week on average for the last 15 months (lowest week: 25 miles, highest week: 200 miles).
The figure above shows the LDL, HDL, total cholesterol, and triglycerides over this time – nearly 10 years total since I have been getting regular blood tests. Fairly pedestrian numbers, overall. Prior to beginning fasting I was eating a normal American can’t-get-it-into-your-suckhole-fast-enough diet, afraid of too much fat and, as I said above, on a path of weight gain year after year. My highest BMI was 32.2, so not horrible, but on the chunky side. The major change in all of this happened when intermittent fasting began, and the major change among these numbers was with the triglycerides – going from more than 130 mg/dL to 70 mg/dL and below, where it has remained ever since.
Other signals are hard to extract from this data, but there appears to be an uptick in HDL and total cholesterol upon starting consistent bike riding. Although the consensus among people who are thinking critically is that your total cholesterol measurement is nearly worthless by itself, it is included in a calculation of your remnant cholesterol, which is the total cholesterol less then LDL + HDL. Mine is plotted below, with a notable drop upon beginning fasting, and an as yet unclear effect from cycling. Elevated remnant cholesterol (in this study, above 24 mg/dL) is associated with increased risk of Athersclerotic Cardiovascular Disease (ASCVD).
The plot just above is another indicator of ASCVD risk plotted over time – the ratio of triglycerides to HDL. Similar story as with the remnant cholesterol. In fact, if you scroll by too quickly it’s easy to think that they are the same plot. Looking at the figure below, when plotted against each other, I’ll be darned if the remnant cholesterol doesn’t correlate decently well with the triglyceride/HDL ratio. For as much as my historical values cluster into two distinct patches, this is another area where I appear to have switched gears. Remnant cholesterol measurements above 15 mg/dL and triglyceride/HDL ratios more than 2.5 have been associated with increased risk of cardiovascular disease.
So, these are some interesting developments over time and it has been greatly empowering to see that I can, in fact, control significant aspects of my health through eating. Seeing these numbers and thinking what they mean and how they reflect various processes ongoing in my body is a fascinating illumination of a subject which is not perfectly understood. Lipids paint part of the picture, and glucose paints another part of it. I recently concluded a 3 week period with a Continuous Glucose Monitor (CGM), and will write about that in the coming weeks.