@photobiogenesis: Thoughts on the relationship b...

Thoughts on the relationship between deuterium and diet

For some time now I've written about deuterium, the "heavy" form of hydrogen which contains an extra neutron in its nucleus

This produces a "deuteron" instead of a proton, and deuterons move through proton-driven reactions exponentially more slowly due to the kinetic isotope effect

Deuterium has been associated with reduced mitochondrial metabolism and other metabolic impairments, so it's useful to limit it in the diet

This raises the question, what's the relationship between deuterium and different chain length fats?

Short chain fats are more common in dairy, while medium chain fats are abundant in tropical highly saturated oils like coconut and palm kernel oil

Lipid saturation is tuned to latitude, light, and environmental temperature

This is why cold water fish are rich in highly unsaturated omega-3 fats, for example

The double bonds in unsaturated fats reduce Van der Waals forces between lipids, normally at cold temperatures this attractive force causes them to bind together rigidly

Van der Waals interactions occur when fluctuations in the electron structure of the hydrogen in lipids sync up, and double bonds work as a defect that limits this

This is also why oils from fish in cold water, and seeds which are exposed to cold winters, both tend to be highly unsaturated

In contrast, coconut and palm oil are highly saturated

Since plants aren't thermogenic in the way mammals are, they rely on ambient temperature to determine their lipid composition

High heat and light near the equator is associated with greater ROS generation, so it benefits these plants to use highly oxidation-resistant saturated fats instead

The high heat environment also dramatically increases the risk of potential fungal or bacterial infections in the fruit/seed

It turns out that medium chain fats like lauric and caprylic acid have antibiotic and antifungal effects, so these plants evolved medium-chain acyl-ACP thioesterase (MCTE) enzymes which cap fat synthesis early before they reach long chain length

Deuterium is also tuned to latitude, altitude, and light

The "heavy" nature of deuterium causes it to precipitate out first in rainfall, so most of the world's deuterium is found in the ocean and closer to the equator

Global weather cycles act to naturally deplete deuterium for organisms living at high altitude and high latitude

It turns out that cells use a similar "cycling" process to deplete deuterium during metabolism as well

I've talked about this before in several contexts

Glycolysis includes several key reactions in which hydrogen is taken out as water, and immediately replaced with a different hydrogen atom from water

This seems superfluous until you realize that if a deuterium is sitting at that site, it will be cleared regardless since the enzyme is selective for that hydrogen position alone

When it comes to selecting a replacement however, there are numerous water molecules to choose from so it's far more likely the reaction will occur with light hydrogen rather than deuterium

All the steps that involve these hydrogen-swap reactions are also bidirectional, so they can cycle if needed

This means glycolysis moves deuterium out of pyruvate and into cell water

Beta-oxidation, the breakdown of fats into multiple molecules of acetyl-coa, uses a different mechanism that depletes deuterium less effectively

In general hydrogen atoms from lipids are fed directly into the electron transport chain without the same cycling with water seen in glycolysis

Glycolysis feeds solely into complex I of the ETC through NAD+, while beta oxidation makes use of both complex I and complex II via FAD+

Beta oxidation also produces less CO2 and ATP per mole of oxygen, though beta oxidation also creates more ATP total due to the greater caloric density of lipids vs carbs

The latitude, elevation, and mechanism through which lipids are created, all influences the deuterium content of food

In general, the deuterium content of sugars and carbohydrates is higher than in fats, while animal fats are lower in deuterium than vegetable oils

Interestingly grains and industrial seed oils are some of the higher deuterium foods, while coconut oil is the lowest deuterium food tested at 110 ppm

What's the reason for this difference?

Since deuterium research is still in its infancy it's difficult to say for sure, but I'll speculate on a few mechanisms

Plants funnel protons into glucose synthesis in the Calvin cycle using six molecules of the reducing agent (electron and proton donor) NADPH

NADPH is produced via the thylakoid electron transport chain, which uses NADP+ reductase

As far as I can tell, while protons that move through the thylakoid ATPase are filtered through the ETC first, protons used by NADP+ reductase partially or completely come from the stroma side and are less deuterium depleted

This makes carbohydrates synthesized by plants inherently higher in deuterium (around 150ppm)

When plants synthesize lipids they funnel glucose through glycolysis to create pyruvate, which is then converted into acetyl-coa

Plants use the same fatty acid synthase enzymes, which then convert acetyl-coa to malonyl-coa which is then built into various lipids

Since glycolysis depletes deuterium plant fats are generally lower in deuterium, but not fully deuterium depleted

Laszlo Boros and Stephanie Seneff, two of the leading researchers discussing deuterium, suggest that the unexpectedly high level of deuterium in industrial seed oils may stem from the use of solvent like hexane which may act as a deuterium source

This suggests that cold pressed oils should be lower in deuterium than cheap canola or soybean oil

My personal theory is that overfarming and monocrops may play a role in higher deuterium food as well

Plants might preferentially absorb lighter isotopes like deuterium from soil first, leaving heavy isotopes behind

But when light isotopes are depleted with repeat farming, soil deuterium content could increase over time

Loss of deuterium-depleting bacteria and fungi from the use of pesticides could play a role as well

Ruminant fat tends to be more deuterium depleted, since its a
either derived from fiber fermentation into short chain fats in the gut, or produced from acetyl-coa derived from the Krebs cycle

Deuterium content of animal fat depends strongly on feed however, grain-fed fat is lower in deuterium than grains but still higher than pastured animal fat

Boros et al. have a good study on this
t.co/Jn6qXl3Xys

Light environment can also drive deuterium depletion as well, and long days with high sun exposure could improve the use of higher deuterium foods

Light stimulates various redox reactions through the photoelectric effect

Infrared light enhances function of the electron transport chain by improving oxygen binding to cytochrome C oxidase and displacing nitric oxide

These and other reactions may reduce or eliminate negative impact of deuterium on ATPase function
sciencedirect.com/science/articl…

On the other hand, deuterium is not an entirely negative dietary component

Rodents fed 40ppm deuterium depleted water will not lower circulating deuterium levels to below 90-100ppm, almost as if excretion is restricted with low dietary intake
romj.org/2014-0201

It turns out to be essential for growth and stability in proteins

Deuterium improves polymerization of proteins like tubulin into microtubules, and preferentially accumulates in proline in collagen

It acts as a growth and cell division stimulus, which seems to play a role in its anti-cancer effects, but could also make the use of DDW a problem in childhood development or healing

I believe that deuteration of proteins improves their stability when conducting electrons and protons, as a similar technique is used with deuterium-rich gas to stabilize silicon circuits

Overall it doesn't make sense to minimize deuterium completely in any context

So where does this leave us?

Animal fat deuterium content mirrors their dietary intake, so to avoid skewing deuterium/hydrogen ratio its best to eat pastured meat or wild game

Industrial seed oils and grains are particularly high in deuterium due to processing and poor farming practices and should also be avoided

Coconut oil is an exception to the rule that deuterium normally concentrates in the ocean and near the equator, and 110ppm deuterium is close to the deuterium content of our mitochondria

Sunlight improves proton and electron flow through the ETC and enhances respiration in general, which should mitigate the impact of high deuterium intake near the equator

Now for the controversial points:

Deuterium stabilizes the conductive proteins like tubulin and collagen, and seems to increase their stability and formation

There's no data I've seen to show a ketogenic diet will deplete deuterium

If we want to keep deuterium in proteins where it belongs, and out of the ETC, the fact that glycolysis has extra deuterium filtration built in means it's not inferior to beta-oxidation

If anything, deuterium from fats may be more likely to enter the ETC than deuterium from carbs

Because of this, I would focus on short and medium chain fats, as these tend to be lower in deuterium, and if you eat animal fat make sure it's pastured or wild game

Carbohydrate sources like fruit and vegetables matter less, but it's still important to avoid industrial grains, processed food, etc

I wouldn't use DDW outside the context of a disease like cancer personally

More on seasonal eating

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Deuterium as a growth regulator

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