@photobiogenesis: The most underrated dietary fa...

The most underrated dietary factor to focus on is shifting dietary fat intake away from long-chain saturated fats, toward short and medium-chain saturated fats, and toward odd-chain saturated fats

For now it feels like I'm the only one talking about chain length

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There are different nuances to this, but the biggest point I've argued is that we now consume much more palmitic acid (a 16 carbon long chain saturated fat) than our ancestors

The same is true for myristic acid (14 carbons) as well

Palmitic acid in particular is problematic

The main reason for this is its accumulation in cell stress

When people talk about free fatty acids, visceral fat synthesis, and insulin resistance, they all boil down to high free palmitic acid levels in the cell cytosol

In cases of energy surplus or impaired metabolism, excess acetyl-coa is carboxylated by ACC into another intermediate called malonyl-coa

Fatty acid synthase, another enzyme implicated in various diseases, including cancer, drives conversion of malonyl-coa into palmitic acid

When a human or animal is obese, the majority of the fatty acids they create are in the form of palmitic acid

This is also the case in industrial agriculture, where cows are fed grains, low fiber diets, and given antibiotics, in order to make them store more carbohydrates as fat

This results in modern meat containing previously unheard of levels of palmitic acid and far more fat in general vs wild meat

This is why I'm so adamant about eating wild game like bison, elk, venison, and boar, instead of modern industrial meat

Palmitic acid and other long-chain saturated fats drive cell stress through several mechanisms

Free PA blocks downstream signals from insulin receptors, and this is now thought to be the primary mechanism behind insulin resistance

While MUFAs like oleic acid are protective

This is also implicated in general inflammation and cytokine release, via palmitic acid's activation of TLR4 receptors in the gut and brain

Palmitic acid enhances response to bacterial endotoxin
nature.com/articles/s4159…

And contributes to neural stress and brain inflammation
journals.physiology.org/doi/abs/10.115…

Now this is definitely an issue in obesity, in which case fatty acid synthase enzymes are over-activated, and free palmitic acid is being liberated into organs like the brain, liver, and pancreas

But what are the impacts of dietary long-chain saturated fat intake?

It turns out there are a few different avenues of research on this question

This study found that the MUFA oleic acid improved resting total daily energy expenditure, while palmitic acid lowered it
sciencedirect.com/science/articl…

This study points out a number of problems in palmitic acid metabolism
lipidjournal.com/article/S1933-…

- Palmitic acid synthesis is increased in low-fat diets, so avoiding fat is not a good solution

- Palmitic acid from food does influence circulating levels

- The increase in heart disease seen in RCTs and observational studies in saturated fat intake are mostly attributable to long-chain saturated fats and their ability to increase LDL particle count and skew LDL/HDL ratio

- Palmitic acid has a FAR greater
impact when obesity and insulin resistance are already present, as more PA is found in the "free" form in these individuals

However, this article is another good overview of many sides of this question
frontiersin.org/articles/10.33…

It makes several good points:

- PA and myristic acid both negatively affect HDL/total cholesterol ratio, and increase LDL particle number, though this will have far worse effects when combined with other risk factors

- The body desaturates some dietary palmitic acid to MUFA as a protective mechanism

- Many studies highlight the impact of PA by swapping it with things like omega-3 fats which would normally be protective against free fatty acids

- Replacing palmitic acid with PUFA will skew PUFA intake too high, causing problems of its own

Lastly, both palmitic acid and myristic acid have been shown to directly elevate apoB, the best overall predictor of heart disease since it's a proxy for LDL particle count
ahajournals.org/doi/pdf/10.116…

Remember that heart disease is the number one cause of death in the United States, and increased LDL particle count and apoB is the closest predictor of mortality, so this is the biggest cause for concern here

I wrote a previous thread on this topic for those interested:

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So where does this leave us?

I'm not in favor of replacing palmitic acid and myristic acid with omega-6 or omega-3 PUFA, as the amount you'd need to swap would be excessive

Our bodies need fairly limited amounts of PUFA, and the O3:O6 ratio needs to be balanced

We could also swap some long-chain SFAs for carbohydrates, and this seems to be neutral or mildly beneficial as far as I can tell

However there's also a third option... focusing instead on saturated fat sources rich in short and medium chain fats rather than long chain fats!

This is the approach I've landed on personally

Let's look at some of the benefits of short and medium chain length

These include fats like lauric, capric, caprylic, caproic, and butyric acid, all of which have very interesting effects

Lauric acid is the most abundant in food

It only slightly raises LDL while significantly improving HDL, so it creates a more favorable ratio

In general, the shorter the chain length the less a fat raises LDL particle count (the exception is stearic acid C18 which is neutral)
openheart.bmj.com/content/3/2/e0…

Medium and short chain length fats also bypass the carnitine shuttle and enter mitochondria more quickly

MCFs increase metabolic rate in the short term, increase levels of acetyl-coa, produce a thermogenic effect, and even elevate circulating ketones without protein catabolism

Short chain fats like butyrate can either be acquired from food, or produced by gut bacteria digesting soluble fiber

Dairy products are high in butyrate when ruminants are grassfed and eating a high fiber diet

Butyrate has potent anti-inflammatory effects, and promotes neuroplasticity by acting as an HDAC inhibitor

Something I find really interesting is that the body even has a receptor system activated by different chain lengths

Short and medium chain saturated fats activate FFAR2 and FFAR3, both of which are being studied as targets to protect against diabetes and obesity

I'll expand more on the benefits of short chain fats in later writing

The last thing I want to touch on is the presence of odd-chain saturated fats in certain foods

There's are incredibly beneficial for several reasons, they act as HDAC inhibitors, have antibiotic properties, and enhance mitochondrial metabolism by skipping acetyl-coa to direct increase succinyl-coa, as well as feeding electrons into the ETC

Here's an excerpt from my article on odd-chain fats and valerian from last year
patreon.com/posts/89818073…

So we have potentially negative effects from palmitic and myristic acid, and huge positive effects from short, medium, and odd-chain saturated fats

How do we shift towards the positives and away from the negatives?

The single best way to balance this equation is by shifting away from beef fat, butter, and ghee, and toward wild game fat, milk fat, cream, and coconut oil

Coconut oil is VERY high in short and medium chain fats compared with butter, 50% of its fat content is lauric acid while palmitic only makes up 8%

Palm kernel oil is very similar, and is superior to palm oil itself

In comparison, beef fat and butter contain ~25% palmitic and are very low in short and medium chain fats

Milk fat is also similar to butter, with 25-30% palmitic acid, but it contains around 10-15% short and medium chain fats, as much as 5% of that being butyrate

It also contains beneficial CLA, vaccenic acid, and pentadecanoic acid in smaller amounts

Butter and milk fat are similar and somewhat interchangeable, the issue is that butter is often consumed in excess in the absence of other nutrients

Small amounts of butter will have similar benefits to milk, and grassfed will have lower palmitic acid generally

In general I prefer milk as a whole food, and coconut oil or olive oil as cooking oils

This also begs the question...

What about people eating a healthy diet in general but lots of palmitic acid?

This is fairly common in "high fat" or low carb circles, and the outcome seems to be that high metabolism, good thyroid function, and good mitochondrial function will mitigate most issues

Problems occur when a stimulus of de novo lipogenesis like slow metabolism or high calorie malnutrition is paired with high palmitic acid consumption

This scenario is a recipe for metabolic dysfunction and heart disease, and replacing long chain for short and medium chain fats may be therapeutic

Given that these shorter chain fats provide so many benefits, even if we consider palmitic acid totally neutral it would still be worthwhile to replace it with them!

This paper is also very key

It found that circulating long chain fats was one of the closest predictors of short lifespan in mammals

This includes both palmitic and myristic acid and long chain omega-6 or omega-3 fats like arachidonic acid or DHA

All of these fats are fine, but optimal levels are likely in some moderation, especially with highly unsaturated long chain omega-3/6 fats

High circulating free fatty acids, excessive long chain fats, and excessive membrane peroxidation, are all associated with shorter lifespan in mammals

To summarize:

- Long chain fats like palmitic and myristic acid are associated with heart disease, inflammation, and insulin resistance in various organs

- This causes the biggest problem when metabolism is impaired or in a state of high calorie malnutrition, since de novo lipogenesis accumulates these fats directly, and high dietary intake compounds this

- Long chain unsaturated fat intake of both omega-6 and omega-3 should not replace long chain SFAs as these are only needed in small amounts and excess accumulation causes issues

- Carbohydrates can be used to replace long chain SFAs, but an even better replacement is with short and medium chain SFAs

- In practice this means swapping industrial animal fat with fat from milk, cheese, and coconut oil or palm kernel oil, these sources also provide beneficial odd-chain fats as well

- The optimal ratio of fatty acids seems to be high MUFA and short/medium SFAs, while consuming PUFA in moderation with balance between O3/O6, and consuming long chain SFAs in moderation

That's all for now, I'll continue fleshing out the mechanisms behind these ideas in future threads and articles

For those who want to see more of my previous writing on this subject, I suggest these articles

GABA, Valerian, and odd-chain saturated fats
patreon.com/posts/89818073…

Breaking beef: how we ruined industrial agriculture
patreon.com/posts/62863199…

More data on wild game vs industrial meat

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