An optimal metabolism: a look at the furnace within

Why can some people eat a high carb diet and flourish?

Why does some nootropics work for some but not for others?

Why does one person get great results from one supplement, whereas another gets the opposite reaction?

Let’s take dopaminergics for example. One person might feel great whereas another feel anxious and wired.

Most of it comes down to the state of the cell, specifically the redox state.

Cellular redox state

The body is composed of amino acids which regulate most enzymatic functions and processes in the body. One important example of this is the amino acid cysteine. Cysteine is linked to many other amino acids in many enzymes, receptors, etc. When a free radical oxidizes the cysteine, it changes the function of that enzyme or receptor or whatever it might be. Cysteine is the reduced form ad when it becomes oxidized, it turns to cystine. The cysteine to cystine ratio indicates a redox balance.

There are many redox couples in a cell that work together to maintain the redox environment. For example, there is the cysteine:cystine, reduced/oxidized glutathione (GSH/GSSG) and NAD:NADH redox couples.

Each couple is either in a reduced or an oxidized state.

Some couples include:

  • NAD:NADH ratio
  • NADPH:NADP+ ratio (maintained at around −400 mV)
  • GSH:GSSG ratio (reduced/oxidized glutathione (GSH/GSSG), which is often reported as the cell potential, is maintained around -280 mV in the mitochondria and about -260 mV to -200 mV in the cytosol) (R)
  • Cysteine:cystine (Cys:CySS) ratio (it has an intracellular value of −160 mV, whereas in plasma it averages around −80 mV in young, healthy individuals)

Each couple have different levels where it becomes oxidized or reduced. It’s more like a spectrum.

The explanation of a redox potential is as follows:

The redox potential (electromotive force, Eh), is a measure of the tendency of a chemical species to accept or donate electrons. This tendency is quantitatively expressed in millivolts relative to the standard hydrogen electrode reaction (H2/2H+ + 2e). The Eh for an oxidation/reduction couple (e.g., GSH/GSSG) is dependent upon the inherent tendency of the chemical species to accept/donate electrons (Eo) and the concentrations of the respective acceptors and donors, defined by the Nernst equation (e.g., for the GSH/GSSG couple, Eh = Eo + RT/NF ln([GSSG]/[GSH]2).

Complicated explanation, but basically, when the cell is more oxidized, it has a much bigger capacity to accept electrons and prevent oxidative stress. A reduced state is the opposite. I’ll explain more about this concept in just a bit.

So when the body/cells become more reduced, the minus gets bigger, and when it becomes more oxidized, the minus gets smaller. A cell with an Eh of -150mV is very reduced compared to a cell with an Eh of 0mV.

It’s always a balance between the two. Going to far to either side is bad.

For example, the Cys:CySS ratio of a cell becomes more oxidized with aging, cardiovascular disease, diabetes, smoking, etc. And that’s because reactive oxygen species (ROS) production goes up with aging, which oxidizes the cysteine as well as other redox couples. More on ROS production in a second.

On the other hand, a more reduced state promotes the progression of cancer. Even supplementing NAC (N-acetylcysteine), which can increase glutathione can promote the spread of cancer.

NADPH, which is used as a cofactor for many enzymatic functions, is increased in a reduced state. It’s most well known for aiding in the synthesis of glutathione, but it’s also used for the synthesis of estradiol, DHT and cortisol, just to name a few.

Also, when the NADH:NAD ratio is high, as in a reduced state, reactive oxygen specie production is elevated. In a more oxidized state (high NAD to NADH), energy production is enhanced and there is a higher rate of uncoupling. Uncoupling has been shown to extend lifespan, be neuroprotective, lower oxidative stress, improve insulin sensitivity, promote fat loss, heat production, etc.

Measuring redox status

Measuring the NAD:NADH ratio is what matters most to determine cellular heath, but it’s difficult to measure and not readily available to everyone. So that’s why we look at other measures, such as the pyruvate to lactate and β-hydroxybutyrate to acetoacetate (βOHB/Acoc) ratio which will reflect the cytosolic and mitochondrial NAD:NADH ratio respectively.

Lactate and pyruvate in cells are present in a ratio of about 10 whereas the β-hydroxybutyrate to acetoacetate ratio is around 2 (R).

What different redox states look like

Exposure to a more oxidized redox state in liver cells from fed mice had:

  • Increased intracellular hydrogen peroxide without causing oxidative damage.

A more reduced state:

  • Led to increased NADPH and maximal mitochondrial respiratory capacity in liver cells (R). In other words, less uncoupling.
  • Less uncoupling, since glutathione deactivates uncoupling proteins and NADPH and GSH is elevated in a reduced state.
  • Enhanced lipogenesis. Yes, you synthesize much more fat from carbs in a reduced state. That’s why people gain a lot of weight when they come off of a low carb diet, because low carb diets cause a reduced mitochondrial redox state (indicated by elevated βOHB/Acoc ratio).
  • Stimulated gluconeogenesis and glycogen synthesis. Fasting also creates more of a reduced state, which stimulates these processes. So even if fed, you’ll have elevated gluconeogenesis and most likely high blood sugar, as seen in those with diabetes (R).

Trouble with a reduced state

When cysteine becomes oxidized by a free radical, it’s converted to cystine in some circumstances. The extracellular cystine is then imported into the cell to be converted back to cysteine via Slc7a11.

Intracellular cystine imported through system Xc- is the predominant source of cysteine in most cancer cells (R). Cysteine is then either be converted to GSH or exported via neutral amino acid transporters.

As the functional component of system Xc-, which imports extracellular cystine with intracellular glutamate release at a ratio of 1:1, Slc7a11 has diverse functional roles in regulating many pathophysiological processes such as cellular redox homeostasis, ferroptosis, and drug resistance in cancer.

Overexpression of Slc7a11 not only increases GSH, but can also quench free radical by itself, maintaining the cell in a reduced state.

Histone deacetylase inhibitors (HDACi), such as butyrate, niacinamide, etc., are able to inhibit SLC7A11 (R).

Sulforaphane promotes the activity of Slc7a11, thus creating a reduced extracellular Eh(Cys/CySS) and this might fuel the growth of certain cancers (R).

Redox shifts with aging

Aging promotes the oxidation of redox couples. In human plasma, aging is associated with the oxidation of the GSH/GSSG as well as the Cys/CySS redox state after middle-age. In the rat brain, NADPH levels decrease after middle age (R).

This study also found that there is an age-related decrease in intracellular free NADH of brain neurons (R). Also, fixing the Cys/CySS ratio in a more reduced state, increase NADH levels as well. The researchers (mistakingly) reasoned that “This restoration to youthful levels of free NADH could provide the reductive energy for higher rates of oxidative phosphorylation.” (R)

Why is NADH low? What is NADH created from?

If you guessed NAD, you are correct. NAD levels decline with age, so it’s reasonable to assume that NADH might also decrease with age. Their goal was to restore neural energy levels, but they did it with creating a reduced environment. Creating an oxidized environment and/or boosting NAD can also increase total NADH levels. Because breaking glucose and fat down for the production of energy requires NAD. Yes, NADH can be recycled by NAD, but by boosting NADH directly, we could overload the electron transport chain and create and excess of ROS while causes neurological damage.

The reason why NAD and NADPH decline with age is because there is an age-dependent loss of gene expression of key redox-dependent biosynthetic enzymes, NAMPT (nicotinamide phosphoribosyltransferase), and NNT (nicotinamide nucleotide transhydrogenase) (R).

NAMPT is the rate-limited step for NAD synthesis, and NNT (located in the mitochondrial membrane) transfers hydride from NADH to NADP + coupled to proton pumping across the inner mitochondrial membrane. So the more glucose and fat are broken down (NADH is produced from NAD) and the faster the electron transport chain runs, the more NADPH could be produced.

However, in an oxidized state, there is a higher level of uncoupling which lowers NADPH production. But this is totally fine since uncoupling lowers oxidative stress and protects against it.

Simply increasing NAD in neurons with niacinamide can restore NADPH and glutathione deficits caused by aging (R). No need to take NAC or anything.

Oxidative/reduced state and ROS

Let’s discuss where most of the ROS comes from.

There is ROS (reactive oxygen species) and RNS (reactive nitrogen species).

ROS include superoxide, hydrogen peroxide and hydroxyl radical.

  • Superoxide is generated mostly through the electron transport chain and NADPH oxidase (NOX).
  • Most hydrogen peroxide (H2O2) is produced from superoxide via the enzyme superoxide dismutase.
  • A hydroxyl radical can be created when superoxide or H2O2 reacts with iron or copper.

RNS include nitric oxide and peroxynitrite (ONOO).

  • Nitric oxide is created through nitric oxide synthase (NOS), of which there are 3 enzymes; endothelial NOS (eNOS), neuronal NOS (nNOS) and inducible NOS (iNOS). Learn more about NO here why excess is bad and how to block it.
  • Peroxynitrite is created when NO reacts with superoxide.

In a reduced state, more NADPH and GSH are produced which quenches free radicals and lowers oxidative stress. A highly reduced state doesn’t mean that there is less ROS production, it just means that ROS detox is higher than ROS production.

A certain amount of ROS is needed for various intracellular signaling pathways and physiological events such as stem cell renewal, immune response, insulin synthesis and vascular tones.

However, on the other hand, too much ROS is destructive and leads to cell death.

NADPH oxidase induced ROS production

NADPH is used by NADPH oxidase (NOX) to produce ROS. So there are cases where a highly reduced state can also lead to excess oxidative stress. Using an oxidizing agent, such as beta-lapachone, lowers NADPH dramatically and creates an oxidized environment while lowering excess ROS. This property helps to protect organs (e.g. kidney) against excess oxidative damage.

Multiple studies have shown that beta-lapachone (βL), an oxidizing agent, is protective against kidney dysfunction, pancreatitis (R), ischemia/reperfusion (R), etc, by lowering the cofactor for NOX, namely NADPH. So instead of boosting glutathione to quench ROS, rather reduce ROS production.

βL treatment significantly lowered the cellular NAD(P)H:NAD(P)(+) ratio and dramatically reduced NOX activity in the kidneys of HS diet-fed DS rats. In accordance with this, total ROS production and expression of oxidative adducts also decreased in the βL-treated group.


Electron transport chain as a source of ROS

There is 5 complexes in the ETC. NADH donates its electrons to complex I and FADH2 donates its electrons to complex II. Complex I & II passes their electrons on to complex III, then cytochrome C oxides and complex IV, where water is created.

The ETC creates a charge which then drives protons out of the mitochondria. The protons can then re-enter the mitochondria through complex V (ATP synthase), where it then drives ATP synthesis.

These complexes are stabilized by cardiolipin. When these complexes are damaged and unstable, instead of passing their electrons onwards, the electrons leak out, react with oxygen and create the free radical called superoxide.

The most significant source of ROS production in a reduced state is complex I. Where excess fat oxidation is taking place, most of the CoQ is already reduced by the FADH2, so then there are limited CoQ for the NADH (coming mostly from glucose oxidation) to donate their electrons to. A high CoQH:CoQ and NADH:NADH ratio leads to excess ROS production.

The ROS produced can then damage the other complexes as well, leading to more ROS production all over. Too much ROS damages the mitochondria, which then signals cell destruction. However, an excess of damaged cells can overwhelm the body’s ability to break all the cells down (mitophagy). In a state of excess ROS, there’ll be an excess of small, fragmented, ROS producing cells that are wreaking havoc.

As a compensatory mechanism for defective ETC, glycolysis (which generates 4 ATP from 1 molecule of glucose compared to 30 ATP through complete oxidative phosphorylation) becomes significantly upregulated. The faster glycolysis runs, especially the specific enzyme glucose-6-phosphate, the more NADPH can be produced through the pentose phosphate pathway (PPP).

This is what happens in cancer. The ETC becomes defective and ROS production sky-rockets. But the cancer cells have to protect themselves, so they upregulate glycolysis and the PPP to produce glutathione. So despite elevated ROS production, glutathione production is so high that it puts cancer cells in a reduced state.

ROS on the NAD levels

Following ischemic insult (a significant reduction in blood flow), the mitochondrial NAD levels are depleted leading to an increase in mitochondrial protein acetylation (an effect that reversibly inhibits enzymatic functions), high ROS production, and excessive mitochondrial fragmentation (excess fission overwhelming mitophagy).

In this study, the administration of a single dose of NMN (nicotinamide mononucleotide) after ischemic insult normalized hippocampal mitochondria NAD pools, protein acetylation, and ROS levels. These changes were dependent on SIRT3 activity which uses NAD as a cofactor (R). Also, the NMN inhibited mitochondrial fission protein, pDrp1(S616) thus preventing excess fragmented mitochondrial formation.

How the redox state affects our hormones and neurotransmitters


Neurotoxicity in a reduced state

Rotenone, which inhibits complex I of the ETC, puts the mitochondria in a more reduced state by increasing the NADH:NAD and CoQH:CoQ (ubiquinol:ubiquinone) ratio. This leads to an increase in ROS, which can then be neurotoxic.

Tyrosine hydroxylase (in the nigrostriatal area of the brain), the enzyme that creates L-dopa from tyrosine (the rate-limited step in dopamine synthesis), is significantly reduced by rotenone treatment (R). This indicates that a reduced state can be detrimental to dopaminergic neurons, whereas an oxidized state with slight uncoupling will be beneficial.

Quinones, which increase the NAD:NADH ratio and lower NADPH (and NOX), are highly neuroprotective.

Exaggerated dopamine response in a reduced state

Dopamine, when acting on the dopamine receptor D1, stimulates the release of intracellular calcium. This is excitatory. An excess of intracellular calcium can cause overexcitation of the brain. A reduced state (low NAD to NADH or low pyruvate to lactate) enhances dopamine-induced calcium signals in cells (R). Pyruvate has the opposite effect because it creates a more oxidized environment, lowering the lactate to pyruvate ratio, increase NAD:NADH, stimulating glucose oxidation, etc. (R)

So if you tend to get anxious or overstimulated from dopaminergics, then you might be in a reduced state and could benefit from oxidizing agents, such as methylene blue, pyruvate, CoQ10, etc.

Glutamate signaling

Glutamate is an excitatory amino acid/neurotransmitter that acts on many glutamate receptors; namely the ionotropic receptors (NMDA, AMPA & Kainate) and the metabotropic glutamate receptor (mGlu1-8).

In normal conditions, glutamate contributes to neuronal growth and even neurotoxicity in large amounts. However, in cancer cells, glutamate serves as an important oncogenic signaling molecule for promoting malignant transformation, tumor proliferation, invasion and metastasis as well as inhibiting the immune system by acting on the glutamate receptors on cancer and non-cancerous cells (R).

Glutamate in normal amounts is necessary, but in excess it’s very bad.

Glutamate receptor signaling

mGlu5, which increases NMDA receptor activity and risk of excitotoxicity, is widely expressed in astrocytes in the brain. This receptor is a target (for antagonism) for pharmacotherapy in Parkinson’s disease (PD). PD is a complex chronic neurodegenerative disorder primarily involving loss of dopaminergic (DAergic) neurons in the substantia nigra pars compacta (SNc), decay of the nigrostriatal tract, symptomatic rigidity, bradykinesia, and resting tremor.

Excess ROS production oxidizes the CyS:CySS ratio which leads to the activation of mGlu5.

Activation of mGlu5 by oxidized extracellular Cys/CySS E(h) was found to affect expression of NF-κB and inducible nitric oxide synthase (iNOS). The results also showed that extracellular Cys/CySS E(h) involved in the activation of mGlu5 controlled cell death and cell activation in neurotoxicity.


A major source of ROS production comes from the mitochondrial, especially the ETC. A defect in one of the complexes of the ETC, can dramatically increase the production of superoxide. Superoxide is rapidly converted to hydrogen peroxide (H2O2) which can then oxidize plasma Cys/CySS.

Even more specifically, it’s the defect of complex I that’s most often the cause of excessive ROS production as seen in studies using rotenone (R). And as I mentioned, defective complex I activity leads to a reduced state (high NADH:NAD and CoQH:CoQ (ubiquinol:ubiquinone) ratio), which causes an excess of ROS production. Taking niacinamide to boost NAD or taking CoQ10, which can shift the balance towards an oxidized state, is highly neuroprotective.

Let’s talk a little more about glutamate signalling.

NMDA signaling is also controlled by the redox state.

Under normal physiological conditions, NMDA receptor activity induces the production of nitric oxide, which can reduce NMDA receptor activity in a negative feedback loop (through S-nitrosylation of cysteines on NMDA receptor subunits, NR1 and NR2A). However, with increased oxidative stress, the production of nitric oxide through NMDA receptor activation can induce the formation of peroxynitrite. This elevated RNS production leads to hyperactivation of the NMDA receptor and neurotoxicity (R).

The NMDA receptor is a major target for treating mental conditions such as depression, anxiety, schizophrenia, fear, paranoia, substance-induced psychosis, substance abuse, obese conditions, Huntington’s disease, Alzheimer’s disease, and neuropsychiatric systemic lupus erythematosus, etc.

A reducing agent, such as NADH or ubiquinol could potentiate the activation of the NMDA receptor, thus leading to excitotoxicity, more ROS production, oxidative stress, neuroinflammation, etc (R).

On the other hand, oxidizing agents, such as NAD, methylene blue, ubiquinone (CoQ10), PQQ, GSSG, dihydrolipoic acid or anything that shifts the balance towards oxidation, can reduce overactivation of the NMDA receptor (R).

Quick word on PQQ & NMDA receptor interactions

PQQ proved to be strongly neuroprotective, not only against excitotoxic injury, but also in in vivo models of both stroke and epilepsy (R).

It appears as if the entire neuroprotective effect of PQQ is attributable to direct oxidation of the NMDA receptor redox site. The results discussed in this study suggest that PQQ, other quinones and redox modulators in the brain, and may represent a novel therapeutic approach for the amelioration of NMDA receptor-mediated neurotoxic injury (R).

NMDA, redox and additive behavior

Overactivation of the glutamatergic system has been shown to play an important role in substance abuse and obese conditions. In particular, it has been previously shown that treatment with N-methyl-D-aspartate receptor (NMDAR) antagonists can attenuate drug cue associations, and reduce cue-induced drug-seeking and relapse-like behavior (R).

So using an oxidizing agent to increase NAD should help against substance abuse, right?

The significance of NAD in addictive disorders stems from the work of Dr. Paul O’ Hollaren (1961) who claimed to have successfully utilized IV NAD+ for the prevention and treatment of over 104 cases of addiction to alcohol and other drugs of abuse, including heroin, opium extract, morphine, dihydromorphine, meperidine, codeine, cocaine, amphetamines, barbiturates and tranquilizers (R). In his retrospective case series, IV NAD+ was administered at a dose of 500–1000 mg added to 300 cc normal saline daily for 4 days, twice per week for a month, followed by a maintenance dose twice per month until addiction was ameliorated, with limited toxic effects.

Lastly, elevated lactate, which indicates a reduced state (low pyruvate to lactate ratio reflects a low NAD to NADH ratio) also activates the NMDA receptors whereas pyruvate has the opposite effect.

Glutamate uptake

Glutamate uptake from synapsis is energy intensive. A low energy and reduced state can lead to excess glutamate accumulating in the synapsis.

Niacinamide, by increasing NAD and increasing the NAD:NADH ratio is able to protect against glutamate excitotoxicity (R).

ATP is needed for the uptake of glutamate and when astrocyte glucose uptake and oxidation is impaired, astrocytes lack the energy to sufficiently clear glutamate from the synapse. This leads to excitatory neurotoxicity, defined in part by increased ROS and mitochondrial dysfunction, and neuronal death.

This is one example of how a low energy state leads to chronic excitation. If you want a relaxed brain that can perform required tasks as needed, then you want an energized brain. Might seem paradoxical, but it’s not.


Treatment with exogenous NAD has been shown to increase adenosine levels which are likely to activate adenosine receptors (R). An excited brain in a reduced state is unable to switch off, leaving you with invasive, obsessive, persistent thoughts overexcitation, anxiety, insomnia, etc.


NAD is necessary for the proper detoxification of serotonin. The main enzyme that breaks serotonin down is called monoamine oxidase-A (MAO-A). MAO-A converts serotonin to 5-hydroxyindole-3-acetaldehyde (5-HIAL), using vitamin B2 and copper as cofactors. 5-HIAL can then be broken down by aldehyde dehydrogenase (using NAD) or aldehyde reductase (using NADH) to form 5-hydroxyindole-3-acetic acid (5-HIAA) and 5-hydroxytryptophol (5-HTOL) respectively.

Alcoholics have an elevated urinary 5-HTOL/5-HIAA ratio, which indicates low NAD, since alcohol lowers NAD and the NAD:NADH ratio. This ratio is a good indication of (recent) alcohol and these people have a higher mortality rate and risk for pneumonia and sepsis (R).

Increasing the NAD:NADH ratio improves intestinal function and lowers serotonin content (R). Excess serotonin contributes to intestinal inflammation, IBD, Chron’s disease, autoimmune conditions, etc.


Cortisol, the active hormone, is created from cortisone via the enzyme 11beta hydroxysteroid dehydrogenase (11β-HSD1) using NADPH. 11β-HSD2, which converts cortisol back to cortisone requires NAD.

Interestingly, glucocorticoid (cortisone and cortisol) levels within cells do not necessarily reflect blood levels due to pre-receptor metabolism by 11β-HSDs (R). 

So a highly reduced state will have an elevated intracellular cortisol:cortisone ratio (more catabolic state), whereas an oxidized state will have higher cortisone:cortisol ratio.

Excess cortisol, driven by 11β-HSD1 overexpression, is overly expressed in diabetes, obesity, hypertension, atherosclerosis, etc.

Epigallocatechin gallate (EGCG; a component found in green tea) lowers cortisol exactly by shifting the redox to a more oxidized state. It lowers the NADPH:NADP ratio, thus reducing the cortisol to cortisone ratio (R).

Furthermore, under oxidizing conditions, cortisol receptor activity is decreased by reduced transport of the receptor into the nucleus and regulation of DNA binding (R).

A more reduced state with elevated NADPH can lead to elevated ROS production (NOX), cortisol synthesis and even enhanced effects of cortisol due to increased transport of the receptor into the nucleus.


The aromatase, which converts testosterone to estradiol and androstenedione to estrone, uses NADPH as a cofactor.

Also, the decline of the NAD/NADH ratio enhances the conversion of estradiol to estrone, resulting in a higher estrone to estradiol ratio. Just because your estradiol is low doesn’t mean that your estrogen is low. Check your estrone and/or estrone-sulfate levels first.


Testosterone production is also an energy-intensive process and requires proper glucose oxidation and NAD levels. A reduced state can lead to lower testosterone production due to reductive stress and low NAD.


5-alpha reductase (5AR), the enzymes that synthesize DHT from testosterone, deactivate cortisol to 5α-dihydrocortisol, convert progesterone to 5α-dihydroprogesterone as of other conversions, use NADPH as a cofactor.

But just because you have high NADPH will mean that you’ll have high DHT. Since DHT can be converted to 3α-diol by 3alpha hydroxysteroid dehydrogenase (3α-HSD) using NADPH as a cofactor. On the other hand, 3α-HSD can use NAD to convert 3α-diol back to DHT.

DHT can also be converted to 3β-diol via 3β-HSD using NADH as a cofactor.


DUOX2 (Dual oxidase 2) creates H2O2 in the thyroid, which is needed for thyroid hormone synthesis, but in large amounts, it’s mutagenic and carcinogenic (R). Estrogen increases DUOX2 (either directly or by increasing NADPH), which overproduces H2O2 and contributes to thyroid cancer.

How to create a more oxidized redox state

#1 Fix electron transport chain

The ETC is where NADH and FADH2 are converted back to NAD and FAD. Good function of each complex (especially complex I) helps to increase NAD.

Low CoQ production (due to statins, hypothyroid, PUFA intake, precursor deficiencies, etc) and low intake of red meat, can create a more reduced state and reduce complex I function.

Vitamin K2 (MK-4), vitamin C and methylene blue intake can rescue defective complex I, II and III function and increase the NAD:NADH ratio.

#2 Increase NAD synthesis

NAD is synthesized from tryptophan, but there can be multiple hiccups along the way. I also don’t recommend taking tryptophan as it can lead to excess serotonin, which is highly detrimental. Tryptophan can also fuel excess quinolinic acid production, which is an NMDA receptor agonist and can promote excitotoxic neuro damage.

Magnesium is required for the conversion of quinolinic acid to NAD, so make sure you get enough magnesium daily.

NAD can also be created from niacin, niacinamide, NMN and NR through the ‘salvage pathway’. This is a much better way of boosting NAD than taking tryptophan. Something as simple as 100mg niacinamide x3 daily can greatly help to increase NAD.

#3 Inhibit NAD catabolism

NAD is utilized by three types of NAD‐consuming enzymes: CD38 NADase/cyclic ADP‐ribose synthases, poly(ADP‐ribose) polymerases (PARPs), and sirtuins (SIRTs).

CD38 inhibitors include quercetin and apigenin. Apple, black currant and guava juice are good sources of quercetin and apigenin.

PARP inhibitors include inosine, quercetin, rutin, naringenin, hesperidin and niacinamide (R, R, R). So basically orange and apple juice and a little bit of niacinamide and inosine supplementation.

#4 Recycle NADH back to NAD

One of the best ways to recycle NADH back to NAD is to activate NAD(P)H:quinone acceptor oxidoreductases (NQO), specifically NQO1, with quinones.

NQO1 converts a quinone and NADPH to a hydroquinone and NADP+ and also NADH to NAD.

Different quinones have different affinities to NQO1 so some will be better at increasing NAD levels at certain doses through NQO1. Meaning vitamin K2 might be better at increasing NAD by supporting the ETC instead of activating NQO1, whereas beta-lapachone might be the reverse.

Other functions of NQO1 include:

  • Being involved in the detoxification and cytoprotection mechanisms of astrocytes.
  • Generating antioxidant forms of ubiquinone, vitamin E, and superoxide reductase (R).

Normal tissue contains low NQO1, so the ROS production is low in normal cells, but high is elevated in cancer/tumor cells, which allows ROS production through NQO1 to destroy cancer cells.

Quinones are able to increase the NAD:NADH ratio, lower lactate, support the ETC, decrease brain edema, reduce BBB permeability as well as elevated levels of nitrate/nitrite, IL-6, IL-1β and TNF-α, etc (R).


Beta-lapachone (βL) prevents aging-related brain dysfunction by increasing NAD levels and the NAD:NADH ratio (R). As already mentioned above in this article, βL lowers NADPH, which lowers NOX activity and oxidative stress, thus being highly protective.


Emodin, a quinone found in cascara sagrada, aloe, Rhubarb, etc, is neuroprotective (R). Emodin is also a strong inhibitor is 11β-HSD1 (R).

Vitamin K2 (MK4)

Vitamin K2 (MK-4) is neuroprotective without increasing GSH (R) and people with multiple sclerosis have significantly reduced vitamin K2 levels (R).


Pyrroloquinoline quinone (PQQ) is also highly neuroprotective and I already covered a little about it above in the glutamate section.

In contrast to PQQ, antioxidant vitamins, ascorbic acid and alpha-tocopherol, had no neuroprotective protective effect (R).

The neurotoxicity of aggregated β-amyloid (Aβ) has been considered to be a critical factor in the pathogenesis of Alzheimer’s disease (AD). It can lead to neurotoxicity in AD by inducing a cascade of oxidation. It was reported that PQQ pretreatment could protect human neuroblastoma SH-SY5Y cells against Aβ-induced neurotoxicity (Zhang et al., 2009). One study established that PQQ may offer an effective therapeutic approach to Parkinson’s disease (PD; Zhang et al., 2009) by preventing α-synuclein amyloid fibril formation (Kobayashi et al., 2006). Zhang and associates also investigated whether PQQ may be a beneficial neuroprotectant in stroke therapy (Zhang et al., 2006). It also has been reported that PQQ may inhibit N-methyl-D-aspartate (NMDA)-induced electrical responses and protect against NMDA-mediated neurotoxic injury (Aizenman et al., 1992; Alexandrova and Bochev, 2005).


Another beneficial effectof PQQ is by upregulating the expression of the galactosidase β-1 (Gal β-1), 4-galactosyltransferase N-acylsphingosine (4-GlcNAc) group which may play an important role in recovery post-TBI (R).


Thymoquinone, a component of Black cumin (Nigella sativa) seeds, is able to increase the expression of NQO1 through Nrf2/ARE signaling, thus exerting a neuroprotective effect (R).

Thymoquinone has also been shown to inhibit many inflammatory mediators, such as  nitric oxide (NO), PGE2, TNF-α, and IL-1β and protect against endotoxin induce neuroinflammation.

Methylene blue

Although methylene blue isn’t a quinone, it’s a good electron acceptor that supports the ETC very effectively. Methylene blue is neuroprotective against excess glutamate by creating a more oxidized state and as well as increasing ATP levels. Methylene blue also inhibits NO and ROS formation and protects against hypoxia.

#5 Remove metabolic brakes

Things that cause oxidative stress and DNA damage and inhibit the ETC will deplete NAD.

A few things that act as metabolic brakes are:

  • Excess NO production, induced most often by gut issues (SIBO, endotoxins, pathogenic gut bacterial byproducts, etc.), inhibits energy production.
  • Endotoxins, caused by an excess of gram-negative gut bacteria. The Bacteroides bacteria is the largest group of gram-negative bacteria in the gut and can easily cause issues if in excess.
  • Stress. Both mental and physical. Consuming aspirin and carbs can help you cope with stress better if you’re unable to escape the stressful situation.
  • Hyperinsulinemia and angiotensin increase the lactate:pyruvate ratio (indicating a reduced state) and synergistically produce superoxide (R).
  • Excess heavy metals, such as iron, copper, lead, cadmium, mercury, etc.
  • Elevated PTH due to low vitamin D and/or calcium intake.
  • EMF exposure, especially if you’re sensitive to it. If you want to learn how to protect against the harmful effects of EMF, check out this article.
  • Mouth breathing
  • Sleep loss

#6 Eat more carbs, speed up the metabolism and and induce uncoupling

There is this (wrong) notion that a fast metabolism speeds up aging and that’s why we want to slow our metabolism with low carb diets, fasting, cold treatment, caloric deficits, etc.

The reason for this is that your metabolism produces ROS as it produces energy. So a faster metabolism would mean more ROS production and faster aging. However, this is not the case.

…individuals with higher oxygen consumption rates can actually have lower levels of H2O2 which is most likely due to elevated uncoupling.

(Reference; thanks Amazoniac for this study)

Elevated uncoupling speeds up the metabolic rate, improves insulin sensitivity, increases the NAD:NADH ratio, increases CO2 production, lowers superoxide and inflammation and protects against oxidative stress. It also increases body temperature, which in turn can help the cells work better to produce energy more effectively.

Also, this study found that there is a strong decrease in absolute and relative (per unit of O2 consumed) mitochondrial oxygen radical production with chronic exercise training, hyperthyroidism, and dietary restriction (R). So even in a hyperthyroid state, ROS is reduce, since thyroid hormones also promote uncoupling.

In order for the mitochondria to reduce oxygen to superoxide, the mitochondrial respiratory chain must be in a highly reduced state (R). Meaning, a reduced state leads to high superoxide production. Higher uncoupling can lead to lower membrane potentials and greater rates of electron and oxygen flow in the respiratory chain (so making it more oxidized).

So, if oxidative damage is an important contributor to aging, then those individuals with a high metabolic rate (and higher uncoupling) may benefit through slower aging (R).

Mice in the upper quartile of metabolic intensities had greater resting oxygen consumption by 17% and lived 36% longer than mice in the lowest intensity quartile. Mitochondria isolated from the skeletal muscle of mice in the upper quartile had higher proton conductance than mitochondria from mice from the lowest quartile. The higher conductance was caused by higher levels of endogenous activators of proton leak through the adenine nucleotide translocase and uncoupling protein-3. Individuals with high metabolism were therefore more uncoupled, had greater resting and total daily energy expenditures and survived longest.


The reason I mention eating carbs is good, is because carb put you in a more oxidized environment that fats does.

Eating more carbs might not be enough

As mentioned earlier, in a reduced state, more lactate is produced, a much greater proportion of carbs can be converted to fat and you can even get hyperglycemia due to overactive gluconeogenesis. plus, you might create more ROS through complex I of the ETC since it’s heavily reduced after a low carb diet.

So when you start eating carbs again, you want to make sure your body is using it properly.

If you want to learn more about how to maximize glucose oxidation, check out this article. Also, check out this article on the dope on blocking fatty acid oxidation.

A few compounds that can improve glucose oxidation, increase the NAD:NADH ratio and that are neuroprotective include:

  • Pyruvate (R). Pyruvate (and ethyl pyruvate) is neuroprotective. quenches free radicals, lowers lactate, stimulates pyruvate dehydrogenase (PDH), increases ATP and the NAD:NADH ratio, and reduces intracellular calcium (R). According to this study, sodium pyruvate (SP) significantly improved glucose metabolism in 3 of 13 brain regions while ethyl pyruvate (EP) improved metabolism in 7 regions compared to saline-treated controls at 24h post-injury (R). Thus, early administration of pyruvate compounds enhanced cerebral glucose metabolism and neuronal survival, with 40mg/kg of EP being as effective as 1000mg/kg of SP (R). Pyrucet from Idealabs is where I get my ethyl pyruvate.
  • Vitamin B1 (R)
  • Methylene blue
  • CoQ10
  • Magnesium
  • Niacinamide (R). Combining niacinamide with progesterone is even more beneficial than either one alone (R).


Now you know what a true metabolism should look like and why some people do good on a high carb diet and others don’t, why some responds better to supplements/nootropics than others and so on.

Here is the NAD boosting stack I’m currently using daily:

  • 500mg niacinamide in the morning (used for NAD synthesis)
  • 3 drops Lapodin (containing beta-lapachone and emodin) sublingually x3 daily (targets NQO1 to boost NAD from NADH)
  • 1mg methylene blue (Oxidal) (electron acceptor to recycle NADH back to NAD)

Keep in mind I have already optimized my glucose oxidation and eliminated any gut irritation by following the guidelines I outline in the Alpha Energy Nutrition Course.

5 of the latest reviews


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