How long does sulforaphane keep?

This 2023 clinical trial with broccoli sprout powder investigated ways of improving blood plasma measurements:

“Quantifying sulforaphane (SFN) and its thiol metabolites in biological samples using liquid chromatography-tandem mass spectrometry is complicated by SFN’s electrophilic nature and the facile dissociation of SFN-thiol conjugates. We used the alkylating agent iodoacetamide (IAA) to both release SFN from protein thiols and force the dissociation of SFN metabolites.

After 15 min of incubation, approximately 90% of the SFN was recovered. After 2 hours of incubation, SFN loss to thiol conjugation was significant, with approximately 30% recovered. The percentage of SFN lost in this manner in human plasma upon protein precipitation would likely be greater than the loss we observed in fetal bovine serum (FBS), as free thiols in human plasma are approximately 6 times higher than in FBS.

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Subjects were 12 healthy, young (19–30 y), men (n = 4), and women (n = 8). They consumed three EnduraCell capsules with water.

Per the manufacturer, each capsule contained 700 mg of 100% whole broccoli sprout powder, including active myrosinase and 21 mg of glucoraphanin, which upon full conversion to SFN would yield ∼8 mg, equaling ∼24 mg of SFN total per three-capsule dose. We note that full conversion to SFN, even with active myrosinase in the supplement, is not expected.

SFN concentrations in plasma increased for all subjects, with the highest being 193 nM for subject 4 one hour post consumption. Asterisks for the 2 and 3 hour time points indicate a p-value of <0.05, comparing that time point to the previous time point for that participant.

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This thiol-blocking method increased SFN percent recovery from FBS from 32 to 94 ± 5%. Applying the method to clinical samples, SFN concentrations were on average 6 times greater than when IAA was omitted.”

https://pubs.acs.org/doi/10.1021/acs.jafc.3c01367 “Bioavailable Sulforaphane Quantitation in Plasma by LC–MS/MS Is Enhanced by Blocking Thiols”


I didn’t highlight subject bioavailability statistics or researcher generalizations. Someday, researchers will be interested and forward-thinking enough about their field to plan ahead and investigate likely occurrences such as:

  • What caused Subjects 3 and 4 to have much higher responses than Subjects 2 and 6?
  • What caused Subjects 5 and 11 to have their highest sulforaphane levels at their 3-hour points, whereas 3-hour points were most other subjects’ lowest levels?

And, of course, what was the actual sulforaphane intake by researcher measurements vs. relying on manufacturer statements? Especially when researcher lab equipment was available to measure that.

This study’s proof of concept demonstrated a 10% sulforaphane loss after 15 minutes, and a 68% loss after two hours. Applying their finding to home sprouting, I wouldn’t expect any advance preparation method of broccoli sprouts or seeds to adequately address sulforaphane degradation.

I’d suggest microwaving up to 60°C (140°F) and/or grinding and/or blending broccoli sprouts and seeds just before eating to optimize your sulforaphane intake. Also, taking the very reactive sulforaphane by itself to optimize your results.

A blood plasma aging clock, Part 2

Quite a few people recently looked at Part 1 which curated “Undulating changes in human plasma proteome across lifespan are linked to disease” in December 2019. Let’s start with a 2023 human study coauthored by Part 1’s lead researcher:

“The aim of this study is to identify a set of proteins in human plasma associated with aging by integration of data of four independent, large-scaled datasets. We identified a set of 273 plasma proteins significantly associated with aging (aging proteins, APs) across these cohorts consisting of healthy individuals and individuals with comorbidities and highlight their biological functions.

arthur and robbins cohorts

Although these presented proteins may be different compared to other presented proteomic clocks [like Part 1’s], this can be explained due to a variety of factors. Across studies there may be several technical factors, such as used anti-coagulants, and biological differences, such as different age ranges, ethnicity and corrections for BMI, which may influence the plasma proteome in the cohorts. To overcome these differences, we focused on the overlap between the different studies as they also present several of these confounding factors.

We show that individuals presenting accelerated or decelerated aging based on their plasma proteome, respectively have a more aged or younger systemic environment. These results provide novel insights in understanding the aging process and its underlying mechanisms and highlight potential modulators contributing to healthy aging.”

https://www.frontiersin.org/articles/10.3389/fragi.2023.1112109/full “Markers of aging: Unsupervised integrated analyses of the human plasma proteome”


A 2023 human study cited the above study and found:

“Our cross-sectional study of adults adherent and non-adherent to recommended lifestyle habits established strong group differences for 39 proteins primarily related to innate immunity and lipoprotein metabolism. Many of these protein differences were best explained by group contrasts in adiposity and visceral fat. The relatively small number of upregulated and downregulated proteins associated with good lifestyle habits should facilitate development of a targeted lifestyle proteomic panel that can be used in future studies to determine efficacy of various prevention and treatment strategies.”

https://www.researchsquare.com/article/rs-3097901/v1 “Adherence to Lifestyle Recommendations Linked to Innate Immunity and Lipoprotein Metabolism: A Cross-Sectional Comparison Using Untargeted Proteomics”


A 2023 human study from Google-owned Calico:

“In most cases, direction of effects between cause-specific and all-cause mortality was concordant, but all-cause mortality association was not statistically significant. Neither do we have insight into conditional causal effects of these proteins nor interaction effects between them.”

https://www.researchsquare.com/article/rs-2626017/v1 “Plasma Proteomic Determinants of Common Causes of Mortality”

“Undulating” in Part 1 described plasma proteins changing over time with peaks at ages 34, 60, and 78. Those peaks don’t provide a base for linearly extrapolating all-cause mortality.

peaks


A 2023 rodent study did a touch better with one of Part 1’s 46 proteins of a conserved aging signature that changed in the same direction with mice and humans, although it didn’t fully investigate protein expression over time.

“Interactions between CHRDL1 levels, age, and plasma lipids that might affect cardiometabolic health should be further investigated.”

https://www.mdpi.com/2073-4409/12/4/624 “Chordin-like 1, a Novel Adipokine, Markedly Promotes Adipogenesis and Lipid Accumulation”

Adverse Childhood Experiences, Part 2

A request was made to present studies that investigated epigenetic impacts of corporal punishments or physical trauma to children or adolescents. Here’s a follow-on of the 2015 Grokking an Adverse Childhood Experiences (ACE) score, since physical abuse is one factor of an ACE score.

1. The largest problem is that a person filling out an ACE questionnaire or Childhood Trauma Questionnaire can’t provide first-hand answers of their own experiences during womb life, infancy, and early childhood. These critical development periods are more impacted by adversity than are later life windows.

Human brains aren’t developed enough before age 3 to provide retrospective answers using cerebral memories. A self-reported ACE score can’t possibly address what happened during the times when we were most vulnerable to disrupted neurodevelopment. And good luck with parents providing factual histories of whether they physically or emotionally neglected, physically or emotionally abused, or otherwise adversely treated their fetus, infant, and young child.

2. Another problem is researchers can pretty much choose whatever questions they want as input criteria. I’ve seen pliable ACE scores developed from 5- to 25-item questionnaires.

Do these questionnaires cover all relevant adverse childhood experiences? For example, are researchers permitted to use as inputs societal-created adversities a child may have lived through such as the Khmer Rouge or Cultural Revolution? Studies are just starting to investigate adverse childhood experiences created by worldwide abuses of authority since 2020.

3. Other problems were discussed in a 2023 paper https://www.sciencedirect.com/science/article/abs/pii/S0145213423003162 “Adverse childhood experiences and adult outcomes using a causal framework perspective: Challenges and opportunities” (not freely available), two of which were:

  • Adding up ACE factors to a cumulative score ignores the impact of synergistic sets. For example, although both cumulative ACE scores are 2, a child who was physically and sexually abused would probably be more adversely affected than a child whose parents divorced or separated, and also had a family member incarcerated.
  • At any given time point, and especially with older people, there’s a potential selection bias against those most affected by adverse childhood experiences, such as those who died.

Using flawed, squishy, cumulative ACE scores as inputs, here are two 2023 studies that found epigenetic associations:

“We tested the following pre-registered hypotheses: Mothers’ adverse childhood experiences are correlated with DNA methylation (DNAm) in peripheral blood during pregnancy (hypothesis 1) and in cord blood samples from newborn infants (hypothesis 2), and women’s depression and anxiety symptoms during pregnancy mediate the association between mothers’ ACE exposure and prenatal/neonatal DNA methylation (hypothesis 3).

  1. Hypothesis 1: In 896 mother−infant pairs with available methylation and ACE exposure data, there were no significant associations between mothers’ ACE score and DNAm from antenatal peripheral blood, after controlling for covariates.
  2. Hypothesis 2: In infant cord blood, there were 5 CpG sites significantly differentially methylated in relation to mothers’ ACEs (false discovery rate < .05), but only in male offspring. Effect sizes were medium. CpG sites were in genes related to mitochondrial function and neuronal development in the cerebellum.
  3. Hypothesis 3: There was no mediation by maternal anxiety/depression symptoms found between mothers’ ACEs score and DNAm in the significant CpG sites in male cord blood.”

https://www.jaacap.org/article/S0890-8567(23)00313-1/fulltext “Epigenetic Intergenerational Transmission: Mothers’ Adverse Childhood Experiences and DNA Methylation”


“In this study, the effect of cumulative ACEs experienced on human maternal DNAm was estimated while accounting for interaction with domains of ACEs in prenatal peripheral blood mononuclear cell samples. Intergenerational transmission of ACE-associated DNAm was explored used paired maternal and neonatal cord blood samples. Replication in buccal samples was also explored.

We used a four-level categorical indicator variable for ACEs exposure: none (0 ACEs), low (1–3 ACEs), moderate (4–6 ACEs), and high (> 6 ACEs). 🙄

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https://www.researchsquare.com/article/rs-2977515/v1 “Effect of Parental Adverse Childhood Experiences on Intergenerational DNA Methylation Signatures”

A flawed broccoli sprouts clinical trial

This 2023 human study investigated commercially available broccoli sprouts’ effects on platelets. I’ll provide details of some procedures, but not of findings, as there were several issues:

“Administration of intervention (sulforaphane/placebo) was followed in 90 min by administration of standardized caloric challenge PhenFlex. Urine samples were classified into three groups: (A) baseline, green line, (B) after intervention or placebo, blue lines, and (C) after PhenFlex challenge, red lines. Samples were divided into 5 timepoints: (0) baseline, (1) <60 min after intervention or placebo, (2) >60 min after intervention or placebo, (3) <60 min after PhenFlex challenge, and (4) >60 min after PhenFlex challenge.

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Shortly (maximum of 3 min) before administration, sprouts were cut approximately 1 cm below the leaves, weighed, and mashed with a small amount of tap water (approximately 13°C) in a kitchen blender for 30s at room temperature. Subsequently, tap water was added to a total amount of 250 mL and participants were instructed to drink the entire mixture.

Commercially available pea sprouts (Affilla Cress®) were used as placebo in this study since pea sprouts do not contain glucoraphanin/sulforaphane. Affilla Cress (16 g) was prepared and administered in a similar fashion. Blinding of participants was ensured by the even appearance of both drinks and the use of nasal plugs during consumption of the investigational products. 🙂

Ninety minutes after administration of investigational products, participants were asked to drink PhenFlex, a high-fat, high-glucose, high-caloric product. PhenFlex mixtures were freshly prepared, and participants were instructed to consume the drink within 5 min.”

https://www.frontiersin.org/articles/10.3389/fnut.2023.1204561/full “The beneficial effect of sulforaphane on platelet responsiveness during caloric load: a single-intake, double-blind, placebo-controlled, crossover trial in healthy participants”


Two main issues were:

1. It was stated throughout that sulforaphane did or could do this and that. None of this was supported by sulforaphane intake measurements / estimates, although measuring equipment was available.

Researchers couldn’t assume that blending 16 grams of broccoli sprouts of unknown age creates x amount of sulforaphane. 3-day-old broccoli sprouts have the optimal yields measured 6 broccoli varieties’ sulforaphane content over 3, 5, and 7-day ages, and published 15 different answers.

Sulforaphane and two metabolites’ urinary output was measured. Supposing that only output measurements were adequate leads to the second main issue.

2. Genes were asserted for certain effects. Plausible alternate explanations such as individual differences in gut microbiota composition, excretion, and metabolism weren’t explored.

These researchers knew or should have known about the 2016 https://onlinelibrary.wiley.com/doi/abs/10.1002/mnfr.201600766 “Stabilized Sulforaphane for Clinical Use: Phytochemical Delivery Efficiency” (not freely available). That study measured two known sulforaphane inputs, and in ten people each, blood plasma and urinary outputs.

The first sulforaphane input had sulforaphane bioavailability from 19.5% to 86.9% of dose. The second input ranged from 48% to 96% of dose. Widely different responses to sulforaphane intake prompted those researchers to state:

“These differences in SF bioavailability may be due to differences in gut microbial metabolism, in the levels of drug metabolizing enzymes (e.g. well-known polymorphisms of glutathione S-transferases that catalyze the conjugation of SF with glutathione), and in excretion kinetics. Innate metabolic differences must not be discounted when assessing the metabolism of SF.”

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Comparing ten dietary fibers’ effects on obesity

This 2023 rodent study compared a high-fat high-sugar diet’s deleterious effects with adding ten bioactive dietary fibers vs. adding the weight-loss pill Orlistat vs. a normal diet:

“Different dietary fibers supplementation improved obesity in rats with diversely positive responses, improvement of dyslipidemia, serum hormone, serum metabolome, and gut microbiota disorders.

Model group ate 66.5% normal chow diet, 10% lard, 20% sucrose, 2.5% cholesterol and 1% sodium cholate. Normal group ate normal chow.

Treatment groups ate high-fat high-sugar diet plus 270 mg/kg each of either barley β-glucan, glucomannan, arabinoxylan, inulin, guar gum, xanthan gum, carrageenan, apple pectin, arabinogalactan, or xylan dietary fibers. Orlistat (Y) supplementation was equivalent to 120 mg taken 3 times per day for 70 kg humans.

dietary fiber effects

We found that supplementation with β-glucan, arabinoxylan, xanthan gum, guar gum, apple pectin, carrageenan, inulin, and xylan significantly reduced body weight and dyslipidemia, whereas glucomannan and arabinogalactan did not. Apple pectin, β-glucan and arabinoxylan improved the most biomarkers (15, 17 and 18 kinds) relevant to obesity.

Most dietary fibers improved physiological indicators which have a risk with obesity, including accumulation of body fat, dyslipidemia, glucose metabolic abnormality, oxidative stress, and adipocytokines secreted by adipose tissue, while β-glucan reversed almost all physiological indicators. Consequently, intake of β-glucan could be considered as therapy for obesity management induced by high fat diet.”

https://www.sciencedirect.com/science/article/abs/pii/S0268005X23001637 “Different dietary fibers unequally remodel gut microbiota and charge up anti-obesity effects” (not freely available). Thanks to Dr. Jiajia Wen for providing a copy.


A human equivalent to this study’s 270 mg/kg daily dietary fiber intake is (270 mg x .162) x 70 kg = 3062 mg. I eat > 4 grams of oat β-glucan daily, and much less than that of orange pectin. No human will eat > 10 grams of inulin every day without having severe gastrointestinal adverse effects.

I didn’t curate this study’s gut microbiota findings because it used fecal samples. Per Measuring gut microbiota, Part 1 and Part 2, fecal microbiota don’t adequately represent gut microbiota in either the entire gastrointestinal tract, or in any section of it.

Replicating other studies’ fecal microbiota findings doesn’t advance science when these don’t define subjects’ gastrointestinal tract situations. More work is needed to improve methods of investigating gut microbiota.

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Amphibian epigenetic clocks

This 2023 study of two frog species expanded one of the cited studies in Epigenetic clocks so far in 2022 to include post-embryonic epigenetic clock measurements:

“We generated DNA methylation data from African clawed frogs (Xenopus laevis) and Western clawed frogs (Xenopus tropicalis) and built multiple epigenetic clocks. Dual species clocks were developed that apply to both humans and frogs (human-clawed frog clocks), supporting that epigenetic aging processes are evolutionary conserved outside mammals.

The two species underlying our Xenopus clocks have markedly different maximum lifespans (30.3 for X. laevis and 16 for X. tropicalis), and average ages of sexual maturity (1 year for laevis and 0.375 for tropicalis). When building our Xenopus clocks, we addressed this fact in two ways:

  • In our pan-clock, we used a log-linear transformation of age that effectively normalizes ages with respect to age at sexual maturity.
  • In our relative pan-clock, we instead estimate relative age (chronological age divided by maximum lifespan), which normalizes ages with respect to maximum lifespan.

We also created dual-species clocks, referred to as human-clawed frog clocks, for estimates of chronological age and relative age. Relative age is the ratio of chronological age to maximum lifespan, and takes on values between 0 and 1. Maximum lifespan observed for humans was 122.5 years.

The relative age clock allows for alignment and biologically meaningful comparison between species with different lifespans.

relative age

Previous studies in humans showed that a hallmark of age-related CpGs is their association with target sites of Polycomb repressive complex 2 (PRC2), which gain methylation with age. This feature is fully recapitulated in Xenopus, and physiological significance of this association is an important open question.

PRC2 plays a prominent role during embryonic development and consequently, many aging-clock-associated genes relate to developmental processes. Given its evolutionary conservation from frogs to humans, methylation status of PRC2 targets supports some critical causal relationship to systemic aging.

Since the association with PRC2 with aging stems from analyses of adult postmitotic cells, and of different tissue origin rather than from embryonic cells, it is tempting to speculate that adult methylation status will get important input during embryonic development, the very phase when PRC2 target gene expression is prominent.

Genes associated with both positive and negative age-related CpGs relate to neural processes, although in somewhat opposite direction. While DNAm increase is linked to neural developmental genes, DNAm decrease links to synaptic transmission, roughly corresponding to processes of immature vs. mature neuronal cells, respectively. This leads to the counter-intuitive suggestion that studying Xenopus neural development may yield new insights into biological aging.”

https://link.springer.com/article/10.1007/s11357-023-00840-3 “DNA methylation clocks for clawed frogs reveal evolutionary conservation of epigenetic aging”


I’ve seen dual-species epigenetic clocks – introduced in A rejuvenation therapy and sulforaphane – referenced elsewhere, most recently in Selective Breeding for High Intrinsic Exercise Capacity Slows Pan-Tissue Epigenetic Aging in Rats. These clocks still aren’t in wide use by researchers, though. Don’t know what it will take to persuade researchers to use dual-species relative age clocks in their model organism studies so that they can justifiably invoke human applicability.

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Broccoli seeds and yeast?

This 2023 study created sulforaphane from broccoli seeds at room temperature using a yeast strain that expressed myrosinase enzyme:

“Myrosinase harboring high glucoraphanin-hydrolyzing activity is the key to prepare sulforaphane efficiently. Almost all the reported exogenous myrosinases are extracted obtained from plants by complex steps. In our previous study, it was proved that a Yarrowia lipolytica 20–8 carrying an Arabidopsis thaliana-derived myrosinase gene can be applied to hydrolyze glucoraphenin for efficient preparation of sulforaphene.

Before being evenly crushed, broccoli seeds were incubated at 100 ℃ for 1.5 h to eliminate endogenous myrosinases and epithiospecifier protein. One unit (U) of glucoraphanin-hydrolyzing activity was defined as the amount of enzyme that hydrolyzes glucoraphanin into 1 μmol glucose per minute.

gr3

Yeast whole-cell catalyst of Y. lipolytica 20–8 could yield 10.32 mg (58.22 μmol) sulforaphane from 1 g dried broccoli seeds within 15 min under mild reaction conditions with a conversion rate of 99.86%. This yeast whole-cell catalyst could be employed for efficient and reusable preparation of sulforaphane.”

https://www.sciencedirect.com/science/article/pii/S2590157523001104 “High-level and reusable preparation of sulforaphane by yeast cells expressing myrosinase”


These researchers referenced their 2021 study where they did the same thing with sulforaphene and radish seeds. That caused English-translation confusion in the Abstract and Conclusion sections.

This study’s yeast strain price and/or availability may preclude use for home sprouting. Arabidopsis thaliana is a road-side weed in Eurasia, though, so who knows what a functioning market could deliver?

3-day-old broccoli sprouts have the optimal yields heated broccoli seed powder at 55° C for only 5 minutes – which sufficiently inactivated epithiospecifier protein – vs. this study’s 1.5 hours at 100° C. Would you do that for five minutes, mix in yeast, then wait 15 minutes for a better sulforaphane yield?

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Does eating broccoli sprouts influence biological age?

A 2023 review of 28 human clinical trials investigating broccoli sprout compounds brought up this post’s title by omitting discussion of it:

“In order to determine the effective reference dose of a broccoli sprouts beverage for detoxifying carcinogenic air pollutants (benzene), Chen et al. administrated a drink enriched with glucoraphanin (GR) and sulforaphane (SFN) from 3-day-old broccoli sprouts to healthy adults. Researchers focused on excretion of metabolites SFN-NAC, SFN-CYS, and non-esterified SFN, which represent 80–81%, 12–14%, and 5–7% of total SFN forms, respectively.

Excretion percentage did not change during the intervention, indicating that bioavailability remained constant.

Enhanced excretion of the urinary biomarker of benzene detoxification S-phenylmercapturic acid (SPMA) was measured in urine collected every 12 h during the 10-day intervention. Out of 132 samples analyzed, >95% had detectable concentrations of SPMA, being significantly increased after consumption of the high dose of beverage (600 and 40 μmol GR and SFN, correspondingly), suggesting that consumption of >10 μmol SFN per 24 h may represent the lowest effective dose of the BSE affecting this biomarker.

https://www.mdpi.com/2072-6643/15/6/1424 “Systematic Review on the Metabolic Interest of Glucosinolates and Their Bioactive Derivatives for Human Health”


These reviewers did much hand waving to draw their conclusions. They ignored that the only way randomized trials become better than non-randomized trials is in dealing with confounders.

The largest confounder with glucoraphanin is that an individual’s gut microbiota, not their human cells, metabolize it into isothiocyanates. A glucoraphanin randomized trial has to have sufficient numbers of subjects in each group to adequately deal with confounding individual differences in gut microbiota.

I highlighted the largest of the 28 trials:

Basic RGB

Sulforaphane studies have fewer confounders. Even so, Upgrade your brain’s switchboard with broccoli sprouts stated:

“Power analysis calculations suggest that a sample size of n = 50 would yield a significant result.”

An insufficient number of subjects in both the half dose and full dose groups caused that study’s researchers to frame their results as “suggesting that consumption of >10 μmol SFN per 24 h may..” rather than asserting significant results.


Addressing this post’s title, it’s been ten years since epigenetic clocks came into use. This review highlighted by omission that there still hasn’t been even one investigation of isothiocyanates’ effects on human biological age as measured by epigenetic clocks.

A 40 μmol ≈ 7 mg sulforaphane “high” dose of the cited study is easily achievable with microwaved 3-day-old broccoli sprouts. There’s little question that healthy people activating AMPK, Nrf2, and associated signaling pathways, and inhibiting pro-inflammatory pathways such as NF-κB with sulforaphane, will experience beneficial effects.

The cited study found no change in sulforaphane treatment bioavailability over ten days, and a predecessor study found the same over 12 weeks. I’ll guess those bioavailability findings will extend over longer time periods.

Where are the researchers who will take the next step to show isothiocyanate treatments cause positive changes in epigenetic clock / biological age measurements?

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Peripheral vs. brain epigenetic measurements

This 2023 human study investigated associations of peripheral and brain epigenetic measurements:

“Evaluating DNA methylation of brain tissue is challenging owing to the issue of tissue specificity. Consequently, peripheral surrogate tissues are used, resulting in limited progress compared with other epigenetic studies.

Averaging data for each CpG across individuals, saliva–brain correlation (r = 0.90) was higher than that for blood–brain (r = 0.87) and buccal–brain (r = 0.88) comparisons. Among individual CpGs, blood had the highest proportion of CpGs correlated to the brain at nominally significant levels (19.0%), followed by saliva (14.4%) and buccal (9.8%). However, cross-database correlations of correlation coefficients revealed relatively low brain vs. blood: r = 0.27, saliva: r = 0.18, and buccal: r = 0.24.

The majority of methylation in the brain is most likely not synchronized with methylation in the periphery. Despite this, variable CpGs that correlate in the brain and periphery, although in small numbers, may have biological relevance, and could be useful for inferring brain methylation from peripheral tissues.

This study has six major limitations.”

https://www.nature.com/articles/s41398-023-02370-0 “Cross-tissue correlations of genome-wide DNA methylation in Japanese live human brain and blood, saliva, and buccal epithelial tissues”


Real science is messy. Hypotheses are experimentally reevaluated many, many times under varying conditions. I skip over studies where researchers don’t provide meaningful limitation clauses.

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Sex hormones and epigenetic clocks

This 2023 human study investigated associations among sex hormones and epigenetic clocks:

“We studied associations between sex steroid hormones and DNA methylation-based (DNAm) biomarkers of age and mortality risk including Pheno Age Acceleration (AA), Grim AA, and DNAm-based estimators of Plasminogen Activator Inhibitor 1 (PAI1), and leptin concentrations.

Leptin is a peptide hormone and is associated with regulation of food intake and energy balance. Leptin also influences inflammatory processes, angiogenesis, lipolysis, and neuroplasticity.

PAI1 is a protein that is involved in tissue hemostasis. Previous studies that assessed associations between sex hormones and PAI1 protein concentrations in blood reported conflicting results.

DNAm PAI-1 was shown to be a better surrogate for lifespan than the actual plasma measure, and performs better than Grim AA regarding associations with the comorbidity-index. Another potential benefit of using DNAm-based biomarkers instead of plasma biomarkers is that the DNAm-based biomarkers represent a longer average estimate of biomarker concentration, and are not as affected by day-to-day variations that could bias results.

sex hormones and epigenetic clocks

Associations are represented by colored arrows with the lines’ thickness representing association strength. As the association was measured mainly cross-sectional, association directionality cannot be established.

  • Hormone levels were inversely associated with epigenetic estimators of mortality risk.
  • Sex Hormone Binding Globulin (SHBG) was associated with a decrease in DNAm PAI1 among men and women.
  • Higher testosterone and testosterone/estradiol ratio (TE) were associated with lower DNAm PAI and a younger epigenetic age in men.
  • A decrease in DNAm PAI1 is associated with lower mortality and morbidity risk indicating a potential protective effect of testosterone on lifespan and conceivably cardiovascular health via DNAm PAI1.”

https://www.medrxiv.org/content/10.1101/2023.02.16.23285997v1.full “Higher testosterone and testosterone/estradiol ratio in men are associated with better epigenetic estimators of mortality risk”


Similar to a coauthor’s outstanding A rejuvenation therapy and sulforaphane where he was the lead author, this study may stay in preprint a while because it challenges current paradigms.

Remember that every truth passes through three stages before it’s recognized:

  1. It’s ridiculed; then
  2. It’s opposed; then
  3. It’s regarded as self-evident.

There may be a long lag between Stages 2 and 3 to memory-hole a fading paradigm’s damage. Don’t expect apologies, remediation, or restitution.

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The goddess of destiny

A 2023 human study investigated exercise, klotho gene, and epigenetic clock relationships:

“Named after the spinner of the thread of life, klotho (KL) is involved in the aging process and may act as an anti-aging hormone in mammals. We hypothesize that circulating KL is correlated with age-associated methylation of the KL gene promoter region, and this is one reason for age-related decline in circulating KL.

202 subjects between ages 37 and 85 were included in the study. A great percentage of volunteers participated in the World Rowing Masters Regatta in Velence, Hungary. They were considered to be the trained group (TRND): n = 131; 80 males: age 59.14 ± 10.8; 51 females: age 57.24 ± 9.4. Results were compared to the sedentary group (SED): n = 71; 27 males: age 55.63 ± 13.4; 44 females: age 61.91 ± 10.5.

Circulating level of KL showed a negative correlation with chronological age in the TRND group, but not in the SED group.

klotho and exercise

Examining the relationship between circulating KL level and PhenoAge and GrimAge, KL is associated with PhenoAge acceleration in the TRND group only. It appears that higher KL can decelerate the DNA methylation-based aging process assessed by PhenoAge.

The present study revealed that circulating KL level is associated with exercise status level and general strength level, and is greatly dependent upon exercise-induced DNA methylation.”

https://www.mdpi.com/2073-4425/14/2/525 “The Circulating Level of Klotho Is Not Dependent upon Physical Fitness and Age-Associated Methylation Increases at the Promoter Region of the Klotho Gene”


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Blinded by their paradigm?

This 2022 human study investigated another type of aging clock:

“The glycan clock of age, based entirely on immunoglobulin G (IgG) N-glycans, can predict biological age with high accuracy. Unlike DNA methylation, glycosylation of IgG does not predict chronological age with high accuracy.

Heritability analysis of plasma glycans revealed that the majority of traits have high heritability estimates, indicating a tight genetic control of glycosylation. To better understand genetic and environmental factors influencing glycan clock variation, we performed a heritability analysis on data from two cohorts included in the TwinsUK registry.

Glycosylation is a series of enzymatic reactions in which carbohydrates are attached to other molecules (e.g., proteins or lipids) resulting in formation of complex carbohydrates and glycoconjugates commonly referred to as ‘glycans.’ Glycosylation of IgG antibody is especially interesting as it dramatically affects its function, and acts as a molecular switch between pro- and anti-inflammatory immune responses.

Heritability of the glycan clock was estimated to decompose observed phenotypic variance into three latent sources of variation:

  • A—additive genetic variance [red] represents cumulative impact of genes;
  • C—shared/common environment variance [purple] results from influences to which both members of a twin pair are exposed; and
  • E—unique environment variance [green] is events occurring to one twin but not the other, and includes measurement error.

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Despite tight genetic control of the IgG glycome:

  • Heritability analysis of the glycan clock revealed only a moderate genetic contribution averaging around 39% [A, left side].
  • Including age of the individuals as a covariate in heritability analysis averaged 71% heritability estimates [B, right side].
  • Mean time difference was 7.5 years for points 1 and 2, and 6 years for points 2 and 3.

Observed increase in the genetic component could be a consequence of chronological age as a shared environmental variance characteristic for every individual and determined by their genetic makeup and epigenetic regulation.”

https://www.frontiersin.org/articles/10.3389/fcell.2022.982609/full “Heritability of the glycan clock of biological age”


Although A rejuvenation therapy and sulforaphane was cited, these researchers missed its central premise: Pro-aging epigenetic programming is directional and not purely random. Contrasting their above graphic’s heritability estimates of 39% with the age-regressed, right side’s average 71% could hardly have been more clear in illustrating this fact.

This study instead stated “Aging in general leads to epigenetic mediated deregulation of genes.” This weak sauce accompanied speculations such as “supports the notion that the glycan clock can be rejuvenated by simple lifestyle choices.”

Researchers almost always want to claim being first in finding x, y, or z. These researchers could have done that in this glycan clock study by highlighting an outstanding finding. So what happened?

An alternate explanation to their paradigm blinding them could be sponsor expectations, peer pressures, etc. I’ll ask them about it, and will update here with their response.


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Do broccoli sprouts treat gout and kidney stones?

This 2022 rodent study investigated glucoraphanin’s effects on reducing uric acid:

“Hyperuricemia is a chronic disease characterized by abnormally elevated serum uric acid levels. Sulforaphane could lower uric acid by decreasing urate synthesis and increasing renal urate excretion in hyperuricemic rats.

A hyperuricemia model was established by administering feedstuffs with 4% potassium oxonate and 20% yeast. Forty male Sprague–Dawley rats were randomly divided into the normal control, hyperuricemia, allopurinol, and sulforaphane groups. Animals were treated by oral gavage for six consecutive weeks, and then phenotypic parameters, metabolomic profiling, and metagenomic sequencing were performed.

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We identified succinic acid and oxoglutaric acid as critical host-gut microbiome co-metabolites. Sulforaphane improved diversity of microbial ecosystems and functions, as well as metabolic control of the kidney. Sulforaphane exerted its renoprotective effect through epigenetic modification of Nrf2 and interaction between gut microbiota and epigenetic modification in hyperuricemic rats.

Limitations of this study include:

  1. We used glucoraphanin bioactivated with myrosinase for our experiments. Future experiments may directly involve sulforaphane.
  2. Bioinformatics analysis resulted in speculations that require further experimental testing.
  3. Further investigation of interactions between microbiota and the host epigenome is still needed.”

https://www.sciencedirect.com/science/article/pii/S209012322200251X “Sulforaphane-driven reprogramming of gut microbiome and metabolome ameliorates the progression of hyperuricemia”


It was a stretch to label treatment subjects as the “sulforaphane group” by claiming “Glucoraphanin (10 mg/kg) was metabolized to SFN by myrosinase as described in previous studies.” Both this and the referenced 2014 study “(RS)-glucoraphanin purified from Tuscan black kale and bioactivated with myrosinase enzyme protects against cerebral ischemia/reperfusion injury in rats” measured glucoraphanin and myrosinase, but not sulforaphane.

A human equivalent to this study’s daily glucoraphanin intake of 10 mg / kg weight would be (.162 x 10 mg) x 70 kg = 113 mg. Whether 10 mg was dry or wet weight wasn’t disclosed.

If 10 mg was wet, 113 mg is a little more than twice our model clinical trial’s average glucoraphanin intake of 51 mg fresh weight from eating 30 grams / day of super sprouts. In April 2020’s Understanding a clinical trial’s broccoli sprout amount, a study coauthor said:

“We considered 30 g and 60 g to be 1/2 and 1 portion per day, respectively, of broccoli sprouts. When we carried out tests with consumers, previous to the bioavailability studies, higher amounts per day were not easy to consume and to get eaten by participants.”

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Eat broccoli sprouts for longevity

This 2022 rodent study investigated effects of broccoli sprouts intake on health and longevity:

“The objective of this study was to assess effects of long-term broccoli sprouts (BrSp) feeding on longevity in rats, as well as on cardiometabolic health parameters. Twelve-week-old Long-Evans rats were randomized to control or BrSp groups.

Broccoli seeds were sprouted for 4 days then air dried for 7 days before use. Rats were fed 300 mg/kg body weight BrSp 3 days per week (Monday, Wednesday, Friday, to limit rat agitation) beginning at 4 months of age until death/euthanasia.

Mean age at death for the oldest 25% of male rats was higher in BrSp-fed rats (838 ± 18 days) than controls (754 ± 17 days). In females, BrSp feeding improved survival.

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BrSp feeding of rodents starting at 4 months of age caused:

  1. Extended life span in rats, albeit this was observed predominantly in females;
  2. Reduced body weight gain in females;
  3. Modest improvements in glucose handling in males;
  4. Marked blood pressure reduction in males; and
  5. Modest changes in behavioral traits examined at 18 months in both sexes.

These findings highlight sex-dependent benefits of BrSp on improving longevity and delaying cardiometabolic decline associated with aging in rats.”

https://www.mdpi.com/1660-4601/19/20/13468/htm “Broccoli Sprouts Promote Sex-Dependent Cardiometabolic Health and Longevity in Long-Evans Rats”


A human equivalent to this study’s dose is (.162 x 300 mg/kg)  x 70 kg = 3.4 grams dry weight three times a week. Per Drying broccoli sprouts, dried 3-day-old broccoli sprouts contain 10% moisture, and fresh 3-day-old broccoli sprouts contain 82.6% moisture. So 3.4 grams of broccoli sprout powder may be an approximate equivalent of 3.4 g x (.826 / .1) = 28 grams fresh broccoli sprouts.

Not sure why a dose regimen of “(Monday, Wednesday, Friday, to limit rat agitation)” was necessary, as that limited human applicability, lifespan results, and healthspan results. Still, this study was a step forward, and encouraged further lifespan and healthspan studies on broccoli sprout consumption.

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Eat broccoli sprouts to combat effects of BPA?

This 2022 rodent study investigated abilities of both glucoraphanin and sulforaphane to reduce bisphenol A’s effects:

“There are only a few studies on the anti-obesogenic activity of sulforaphane (SFN) in bisphenol A (BPA)-induced obese C57BL/6J mice and 3T3-L1 cells. BPA is one of the endocrine disrupting chemicals that mimics bioidentical hormones and acts as an active agonist of glucocorticoid receptors to promote adipogenesis.

We investigated anti-obesogenic effects of broccoli sprouts powder (BSP) with a high glucoraphanin (GRA) content, mustard (Sinapis alba L.) seed powder (MSP) that has a high myrosinase activity, and sulforaphane-rich MSP-BSP mixture powder (MBP).

  • GRA content in BSP was 131.11 ± 1.84 μmol/g, and SFN was not detected.
  • SFN content in MBP was 162.29 ± 1.24 μmol/g, and GRA was not detected.
  • GRA and SFN were not detected in MSP.

Mice were administered:

  • BPA (500 μg/kg/day);
  • BPA supplemented with 100 mg/kg/day Gar (BPA + Gar);
  • 15 mg/kg/day MSP (BPA + MSP);
  • 150 mg/kg/day BSP (BPA + BSP); or
  • 100 mg/kg/day MBP (BPA + MBP)

for 12 weeks. The BPA + Gar group served as the positive control group, since studies showed that Garcinia cambogia extract induces weight loss.

bpa weight gain

Mice in the BPA group showed a significantly high body weight and epididymal adipose tissue weight, compared to the ND group mice. MSP treatment had no significant effects. Gar, BSP, and MBP treatment significantly decreased body weight and epididymal adipose tissue weight in BPA-induced obese mice.

BSP and MBP exert anti-obesogenic effects by activating the AMPK signaling pathway. Our results suggest that BSP and MBP could be effective in the treatment and prevention of BPA-induced obesity.”

https://www.mdpi.com/2072-6643/14/18/3814/htm “Anti-Obesogenic Effects of Sulforaphane-Rich Broccoli (Brassica oleracea var. italica) Sprouts and Myrosinase-Rich Mustard (Sinapis alba L.) Seeds In Vitro and In Vivo”


Human daily equivalent doses:

  • Sulforaphane was (.081 * 100 mg) x 70 kg = 567 mg, or (.567 g * 162.29 μmol/g) = 92 μmol. The μmol amount is reasonable, but the mg weight would be intolerable. I’ve contacted these researchers for clarification, and will update with their response.
  • Glucoraphanin in broccoli sprout powder at (.081 * 150 mg) x 70 kg = 851 mg looks reasonable. Broccoli sprout powder vendors recommend 1 gram.

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