The problem: blood pressure
I have a problem with high blood pressure. (Note I do not suffer from any type of diabetes or metabolic syndrome and am not obese: 5’8, 164lbs at the start, BMI 25, top of normal range.) Following a surgical procedure last fall, the surgeon recommended that I try to get my systolic BP down to 120 or lower. My cardiologist prescribed two BP meds, and later tweaked the dosage. My BP flirted with 120 for a while, then edged back up to 140.
What to do? I have an appointment with the cardiologist in May. I can message her anytime. Next step should be to message her and be prescribed a different dosage or a different drug. But I thought that first, I would try a short “N=1” experiment. Anecdotal reports say the Keto diet fixes all sorts of things. Could two weeks on full Keto alter my average BP?
Keto was easy for me to do
A spell on full Keto would be easy because I have in stock several flavors of Keto Chow, a meal replacement designed to support a Keto diet. That was not because I have ever been on a Keto diet.
I live in a fancy Independent Living facility for seniors. We are supplied with three meals a day, normally in a nice dining room but during the pandemic, delivered to our apartments. I don’t care for the timing or content of the usual breakfast delivery, and have chosen to do my own breakfasts for the past year. Lunch and dinner I received as the usual in-house meals.
I have some knowledge of the world of meal replacement products, and a year ago decided to use a meal replacement for my breakfast. I tried several makes and settled on Keto Chow, not because I was into the Keto diet, but because of its wide assortment of flavors and smooth texture. That’s why, at the start of the experiment, I already had a good stock of large bags of Keto Chow, enough to supply all my meals for two weeks and more. I could just cancel all my in-house meal service and go with the Keto Chow.
What I ate
For two weeks my main source of calories was Keto Chow, three shakes a day, mixed to 400 kcal per shake. That’s not sufficient calories for weight maintenance, but I brought in several keto-friendly grocery store items: sausage, cheeses, roast chicken, cashews, dill pickles, canned tuna. I also had a few hard-boiled eggs from the house kitchen.
I bought a jar of natural (no added sugars) peanut butter. One of my favorite snacks was to cut a narrow stick of Havarti cheese and dip it into the oily peanut butter.
I cancelled all house meals for the two weeks. Besides lots of no-cal soft drinks, the above was my diet for the two-week experiment.
What I recorded
I kept the same physical records I have been keeping in a spreadsheet for over a year:
- Blood pressure, 2-4 times a day, using a Wells-Allyn home meter
- Morning weight from a digital scale
- Morning temperature from a digital thermometer
- Stool quality on the Bristol scale plus a note on whether my stool floats or sinks
The latter item is because I’m a touch paranoid about pancreatic function, as someone close to me died of pancreatic cancer.
Effects of a Keto diet
Emotionally, the diet was no problem. I got a bit tired of the shakes despite having a different flavor every meal. I noted the following physical effects.
Stool quality in the first few days strongly suggested incomplete fat metabolism: stool floated and had a paler, yellow-green cast than usual. There was one day of loose, almost diarrhetic stool, which I suspect was caused by some funky “beef chips” I picked up on a whim at Whole Foods. Then the stool settled back down to normal color and mostly sinking, indicating complete fat metabolism. I took that as a sign showing I had reached metabolic ketosis. (I did not have any way to monitor blood ketones.)
I was noticeably more thirsty. More often than previously I would feel very thirsty, and drink 8 ounces or more of liquid. I take this as another sign that I was in metabolic ketosis, or at least, some metabolic state different from previous.
My weight dropped sharply. My weight had been generally stable, on a very slow climb from a post-surgery low of 160 lbs, to 164 lbs over the prior three months. In the first four days of the Keto diet it dropped three pounds, then stabilized, then slowly dropped over the final week to 158.8. That’s a 5+ lbs loss in two weeks, with a noticeable effect on my waist size (belt one notch tighter).
This indicates I was not taking in enough calories for maintenance, despite snacking freely on salted cashews and Havarti dipped in PB. Yes, I am well aware of Keto cooks like Chef Taffy Elrod, who publish cookbooks of yummy Keto meals. I have no cooking facilities other than a fridge, a sink and a microwave. So my ability to have a varied Keto diet was limited to what I could buy at the grocery and prepare with a paring knife and a spoon. Apparently that was not enough, although I wasn’t troubled by hunger at any point.
And the blood pressure?
So what was the result of this short, N=1 experiment? Besides affecting stool quality, thirst, and weight, did my systolic BP show any trend during roughly 10 days in ketosis?
Nope. The dark blue line connects all my BP readings (2, 3 or 4 per day depending on how often I remembered to take it) for the period one week before and two weeks during the diet. The light blue line is a 3-measurement rolling average to smooth out the results.
Being in ketosis might possibly have raised my BP a few points, but that is dubious. It might have made my BP more variable: the dark blue line seems to get more bouncy in the right-side two-thirds of the chart. But really, there’s no result there.
What ketosis definitely did not do is to lower my BP in any meaningful way.
So on the 15th day since the start of the diet, I resumed normal eating with an almond croissant from my local coffee shop.