I’m tied up all weekend with work, so no time to post. Tons of interesting experiments coming up, though:
Flour replacements: Just finished up testing of the last flour, so just need to test how much water each absorbs and write up. Very interesting results, some surprisingly good, some surprisingly bad.
Allergy study: got great feedback on my proposed protocol, ready to finalize & pre-register and get going on the tests.
BP & breathing: got great feedback on my proposed protocol, ready to finalize & pre-register and get going on the tests. I also have preliminary data from exploring different breathing protocols to hone in on the most impactful before starting.
Commute studies: Got curious about how to speed up my commute and have been tracking time using different routes.
If I have time, I’ll post a little during the week so as not to build up a backlog, but at worst will resume next Saturday.
I’ve started paying more attention to my breathing in the past few weeks and have noticed that when I go for a walk in the mornings or a run in the evening, I develop a runny nose that goes away shortly after I go back inside. It’s not terrible, but is annoying and prevents me from breathing comfortably through my nose.
From a quick search, my symptoms match closely with exercise induced rhinitis (list of articles). Numerous studies have found that exercise induced rhinitis is usually caused by allergies. I have never had nasal allergies, but it’s possible I’ve developed them or that they’ve always been mild enough that I haven’t noticed.
I’d like to determine whether my symptoms are, in fact, being caused by allergies and, if so, if there’s any simple interventions I can do to mitigate them.
Here’s my plan:
Step 1: Test if the symptoms are caused by just being outside or only during exercise
Go outside to the same location where I exercise and wait for 30 min. (same length as walks/runs).
Record whether I develop a runny nose and its severity.
Step 2 Test if the symptoms are ameliorated by allergy medication
Take fast-acting allergy medication or a placebo 1 hour before exercising.
Record whether I develop a running nose and its severity.
This experiment will be blinded by placing the pills inside of opaque gel caps and have another person randomize the treatment days for me.
Run the experiment for 10 weekdays & 4 weekend days (exercise locations differ)
If no effect is seen, repeat this experiment with long-acting (24h) allergy medication, but randomize by week instead of by day.
Questions
Does this approach seem reasonable? Any other measurements/tests I should try?
Does anyone else have this problem? If so, any recommendations for interventions to try?
Phase 2: Testing Deep Breathing to Lower Blood Pressure
Approach (details below)
Measure blood pressure and pulse before & after the most well studied protocols as well as normal breathing.
If any protocols show significant reduction in blood pressure, optimize the protocol and design/execute an experiment to test the long term effect.
Analysis
Student’s t-test will be used to test if the blood pressure change for any of the protocols is different from that of normal breathing.
Questions:
Phase 1
Any other metrics I should be looking at?
Does this analytical approach seem reasonable? Are there different statistical approaches I should be taking (details below)?
Phase 2
Has anyone tried this? If so, what breathing protocols have worked for you?
Any suggestions for other interventions to try?
Any comments or critiques of the experimental design or analysis?
Anything else I should be measuring while doing this?
It would significantly improve these studies to have a larger number of participants. If you’re interested in collaborating on this or other scientifically rigorous self-experiments with blood pressure, low-carb foods, supplements, or other health interventions, please let me know in the comments or via the contact form on the right.
Details
Purpose
To identify environmental or controllable factors that have a significant impact on my blood pressure.
To quantify the effect of known interventions for reducing blood pressure.
To find a set of interventions that enable me to reduce my blood pressure below 120/80 mmHg.
Background
Figure 1. Weekly average of blood pressure as measured by Omron home blood pressure monitors.
Figure 2. Cumulative incidence of cardiovascular disease vs. time for different blood pressure groups from a study of the South Korean nationwide health screening database (6.4M participants).
Table 1. Rate of cardiovascular disease for different blood pressure groups from a study of the South Korean nationwide health screening database (6.4M participants).
Given this, I’d like to see if I can reduce my blood pressure and reduce the strain on my heart and circulatory system.
There are numerous medications that lower blood pressure, but all risk of side effects. Before I pursue that route, I’d like to better understand the cause of my elevated blood pressure and see if any diet or lifestyle interventions can ameliorate it.
As mentioned above, I’ve been measuring my blood pressure for the past 4 months, along with blood glucose, sleep, weight, and exercise. This provides a (hopefully) rich dataset for identifying environmental or lifestyle factors that influence my blood pressure. Notably, I’ve noticed that my blood pressure is elevated on days after I’ve had low blood sugar the night before, indicating a possible effect (no statistical analysis done).
Type of exercise the previous day (aerobic vs. strength training) and frequency of aerobic exercise
Manually recorded
Analysis
A mixed effect model will be used to calculate the effect size, standard error, and p-value for the correlation between each metric and systolic and diastolic blood pressure
Effects will be of significant magnitude if a reduction of 5 mmHg can be achieved via a practical variation in the correlating metric.
Given the large number of metrics being looked at, I will use p-value thresholds of:
0.02 for planning testing interventions
0.05 for follow up experiments to confirm the correlation
0.1 for further monitoring/assessment as I get more data
Questions
Any other metrics I should be looking at?
Does this analysis seem reasonable? Are there different statistical approaches I should be taking?
Phase 2: Testing Deep Breathing to Lower Blood Pressure
Background
Numerous studies, reviews, and meta-analyses have shown deep breathing to lower blood pressure in both the short and long-term (example 1, example 2).
Effect sizes are moderate (3-5 mmHg) and statistically significant for large patient populations (>10,000 patients in some studies).
Numerous breathing protocols have been tested, with varying results.
Approach
Measure blood pressure and pulse before & after the most well studied protocols as well as normal breathing.
For each protocol, measure at least three times. If the protocol shows a reduction in blood pressure, measure an additional 5 times to confirm.
Conduct measurements 1/day in the mornings.
If any protocols show significant reduction in blood pressure, optimize the protocol and design/execute an experiment to test the long term effect.
Measurement
Blood pressure and pulse will be measured with an Omron Evolve.
Analysis
Student’s t-test will be used to test if the blood pressure change for any of the protocols is different from that of normal breathing.
Questions
Has anyone tried this? If so, what breathing protocols have worked for you?
Any suggestions for other interventions to try?
Any comments or critiques of the experimental design or analysis?
Anything else I should be measuring while doing this?
Acknowledgements: Thanks /u/genetastic for advice on the statistical analysis!
This post is an update on my experiments to quantify the effect of vinegar on blood glucose & to better understand the underlying mechanism by determining how this effect varies with person/metabolic status, dose, source of calories, and type of acid.
In Phase 1, /u/genetastic, /u/kabong, and I replicated the literature showing that vinegar can reduce the blood sugar impact of complex carbohydrates (white bread). From those experiments, we found that:
Vinegar significantly lowered blood glucose
Peak change in blood glucose & iAuC were reduced by 20% and time to peak blood glucose & initial rise were slowed by 15-20 min. (30-50%).
P-values were all <0.05, with the exception of the drop in iAuC, which was 0.12
The concentration of vinegar we used was extremely unpleasant to consume. So much so that I, at least, wouldn’t be willing to use it for additional experiments, much less daily life.
In this Phase, I tested a more palatable protocol, vinegar diluted in water (~30g vinegar in ~325g water) drank immediately before the meal. Here’s a summary of the results & next steps (full details below):
Diluted vinegar had a statistically significant and meaningful impact on blood glucose compared with no vinagar:
Peak change in blood glucose and iAuC were reduced by ~20% and time to peak was slowed by ~20 min.
P-value was <0.05 for the change in peak blood glucose, but not for iAuC and time to peak.
Diluted vinegar gave very similar results to undiluted, with virtually no change in peak blood glucose and only a modest increase in iAuC and decrease in time to peak. None of these differences were statistically significant.
These results give further evidence that the effect of vinegar on blood glucose is real and provide a practical protocol that can be used for further experiments. For the next phase, I will be testing the following:
Alternate macronutrients (simple sugars, proteins) to determine scope of the effect
Alternate acid sources to test the amylase-inhibition hypothesis
Whether this effect is significant with full meals, including insulin doses
For this last experiment, I will randomly drink 30g ACV in 325g water before my standard breakfast (50g ketochow, 2 tbsp butter, water to 12 oz total volume) and monitor BG impact.
It would significantly improve the study to have a larger number of participants. If you’re interested in collaborating on this or other scientifically rigorous self-experiments with low-carb foods, supplements, or other health interventions, please let me know in the comments or via the contact form on the right.
I’m always looking for collaborators for future experiments. If you’re interested in collaborating on scientifically rigorous self-experiments with low-carb foods, supplements, or other health interventions, please let me know in the comments or via the contact form on the right.
I posted initial results from testing of flour replacements this week. Of the 7 flours I’ve tested so far, all have been pretty good, with peak ∆BG of 16-29% of wheat flour by weight and 9-23% by volume (see post for details).
The post got a huge response, the most site visits and first-day comments on Reddit of any post so far. I’ve definitely hit on something people are interested in. From the comments, I also got tons of new flour replacements to try, almost double what I had found on my own.
Experiments this week focused on flour replacements and vinegar experiments. Next week will focus on continuing both of these, as well as figuring out protocols for some non-food studies I’d like to get going around breathing, blood pressure, and palm-cooling.
– QD
Active & Planned Experiments
Blood Glucose Impact of Low-Carb Foods & Ingredients
Goal: Determine blood glucose impact of low-carb foods and ingredients
