My latest blood test results are in-how’s my biological age?
In the video I discuss my dietary approach prior to my latest blood test, the blood test results, and my plan to improve them with diet going forward.
After going on Joe Rogan’s podcast, Paul Saladino, MD, posted his show notes, which included his blood test results. Based on that data, is his biological age optimal while on a carnivore diet?
Sleep changes during aging may impact Alzheimer’s disease risk, and with the goal of minimizing that risk, can sleep, in particular, levels of deep sleep, be optimized?
Here’s a podcast that was recorded with WildHealth, enjoy!
Germ-free mice (animals don’t have a microbiome) live longer than microbiome-containing mice, but it’s impractical for people to live in a bubble for their entire lifespan. As a more practical approach, which microbiome-derived factors impact lifespan, and can they be modified?
Dietary supplementation with acarbose increases lifespan, and one reason for that may involve reduced circulating levels of glucose, but the other side of that story involves increased gut bacterial production of short chain fatty acids (SCFAs). Whether acarbose will increase lifespan in people is unknown, and with the goal of increasing lifespan, are there other ways to increase SCFAs?
The incidence of fungi bloodstream infections increases during aging-is that a potential explanation for the presence of fungi in the brains of Alzheimer’s disease patients? Rapamycin is a known antifungal-is it effective against fungi that are found in the blood and brain?
Maximal lifespan in calorie restricted (CR) mice can range from 45 – 55 months. In this video, I present data for 3 studies on rapamycin-can it beat CR for maximal lifespan?
In order to slow aging, it’s important to know how circulating biomarkers change during aging, and how these biomarkers are associated with risk of death for all causes. In this video, I discuss blood test data for the oldest old, including centenarians (100 – 104y), semi-centenarians (105 – 109y), and super-centenarians (110y+).
NR and NMN are popular ways to try to boost levels of NAD+, but that approach hasn’t worked every time in human studies. One reason for that may involve CD38, which degrades both NR and NMN. With the goal of boosting NAD+ levels during aging, why does CD38 increase with age, and what can be done about it? All that and more in this video!
Blood urea nitrogen (BUN) is one of the 19 variables found on the biological age calculator, aging.ai. It measures the amount of nitrogen, as contained in urea (i.e., blood urea nitrogen, BUN) in your blood. The reference range for BUN is 5 – 20 mg/dL, but within that range, what’s optimal?
First, BUN increases during aging, from 11 – 13 mg/dL in 20 yr olds to 20 – 22 mg/dL in 90 yr olds (Wang et al. 2017):
The importance of the age-related increase in BUN is illustrated by the finding that risk of death for all causes increases above 15 mg/dL:
Also note that maximally decreased risk for all cause mortality was associated with BUN values between 5 – 15 mg/dL. In addition, even though a BUN value = 20 mg/dL is technically within the reference range, risk of death for all causes would be 50% higher when compared with someone that had BUN levels between 5 – 15 mg/dL. Collectively, based on the aging and all-cause mortality data, I’d argue that 5 – 13 mg/dL may be the optimal range for BUN.
Assuming normal kidney function (see https://michaellustgarten.wordpress.com/2019/11/18/optimizing-biologic-age-creatinine/), if your BUN is higher than 15 mg/dL, can it be reduced? Note that urea production is almost perfectly correlated (r = 0.98) with dietary protein intake (Young et al. 2000):
In other words, the main source of dietary nitrogen is protein, so if you eat a lot of protein, you’ll make a lot of urea. Circulating levels of urea can be easily calculated by measuring BUN, via: Urea [mg/dL]= BUN [mg/dL] * 2.14). Therefore, measuring BUN can then be used to determine if your protein intake is too high or too low.
What’s my BUN? As shown below, I’ve measured BUN 22 times since 2015. In line with the Young et al. (2000) data that showed an almost perfectly linear correlation between dietary nitrogen intake with urea production, similarly, as my dietary protein intake has increased, so have my BUN levels. The correlation between my dietary protein intake with BUN is strong (r = 0.76, R^2 = 0.575, p-value = 4.3E-05):
Note that my BUN is (purposefully) below 15 mg/dL, the upper limit for reduced all-cause mortality risk in Solinger and Rothman (2013), and within the 11 – 13 mg/dL range reported for the 20 yr olds of Wang et al. (2017).
For more recent tracked data, see the video!
References
Solinger AB, Rothman SI. Risks of mortality associated with common laboratory tests: a novel, simple and meaningful way to set decision limits from data available in the Electronic Medical Record. Clin Chem Lab Med. 2013 Sep;51(9):1803-13.
Wang Z, Li L, Glicksberg BS, Israel A, Dudley JT, Ma’ayan A. Predicting age by mining electronic medical records with deep learning characterizes differences between chronological and physiological age. J Biomed Inform. 2017 Dec;76:59-68. doi: 10.1016/j.jbi.2017.11.003.
Young VR, El-Khoury AE, Raguso CA, Forslund AH, Hambraeus L. Rates of urea production and hydrolysis and leucine oxidation change linearly over widely varying protein intakes in healthy adults. J Nutr. 2000 Apr;130(4):761-6.
If you’re interested, please have a look at my book!
Michael Lustgarten 