For today’s edition of Dear Mark, I’m discussing the seemingly evil qualities of palmitic acid, the preferred storage form of body fat in humans and many other mammals. Studies seem to indicate that pure palmitic acid has negative health effects, so should we be avoiding palmitic acid-containing foods like butter, meat, or palm oil? Then, I explain the health effects of eating really fast. As you’ll see, there are quite a few reasons to eat more slowly than quickly. I also include a few tips for fast eaters who want to slow down.

Let’s go:

Hey Mark,

This is something I have been trying to get to the bottom of recently. I have been reading about different saturated fatty acids and their effects on the body. One that always comes up is Palmitic acid. I read that “Palmitic acid is one of the most damaging fats, second only to trans fats in its list of negative health effects” and the same goes for myristic acid. Normally I would dismiss these sorts of claims, but it came from somebody who knows that saturated fats aren’t correlated with heart disease, so this person isn’t in the whole “saturated fats are evil” club.

I would really like to hear your views on this Mark, if some saturated fats are actually harmful, or if it just outdated science.



Ah yes, dastardly palmitic acid. So evil, so toxic that it’s the body’s preferred storage form of energy. Kind of like how we make cholesterol in order to clog our arteries and give ourselves heart disease, our livers convert energy into palmitic acid to commit long, slow, agonizing suicide and develop diabetes. Makes sense.

I certainly love to cook with palmitic acid. Unfortunately, the refined, isolated palmitic acid doesn’t exist in nature, so I got a fancy fractionation machine sitting on my counter that separates the various fatty acids. It works great. Plop in some butter and let the centrifuge spin, spin, spin until the isolated palmitic acid comes out ready to be used.

I’m kidding, of course. The point is that if you take a look at the literature you’ll find evidence that while isolated palmitic acid has some negative effects, palmitic acid mixed with other types of fatty acids and nutrients – also known as food – has a very different effect. In other words, palmitic acid gets an undeserved bad rap. So what does the research show?

1. Palmitic acid lowers expression of the LDL receptor gene. Less LDL receptor activity, more time for LDL to hang around in the bloodstream and cause trouble. That’s not good.

Except a modicum of oleic acid stimulates LDL receptor activity.

2. Palmitic acid is toxic to skeletal muscle cells, impairing glucose uptake and increasing insulin resistance. I for one like my muscle cells to have the ability to accept glucose, so maybe I’ll stop eating palmitic acid.

But arachidonic acid, a polyunsaturated fat found in animal products often alongside palmitic acid, prevents this lipotoxicity.

3. Palmitic acid induces inflammation and disrupts insulin signaling, early signs of diabetes. We don’t want diabetes, so we should probably stop eating any palmitic acid, right?

Except that introducing a little bit of oleic acid, a monounsaturated fat almost invariably found alongside palmitic acid in the animals we eat (or in the olive oil we use to dress our meat), completely obliterates the inflammation.

Heck, even if we do manage to isolate and choke down enough pure palmitic acid to cause problems, our livers can modify some of it to produce oleic acid, thus negating any potential negative effects.

Physiology is quite a thing, huh? It’s amazing how well simply eating food in its natural state and letting your body take care of the rest works. It’s only when we upset the natural order by engaging in biologically inappropriate activities like drinking two sodas a day plus sweet junk food while sitting down for twelve hours a day with a glycogen-replete liver, thus prompting the liver to convert sugar into palmitic acid for storage and circulation because there’s nowhere else for the fructose to go.

I don’t know about you, but the fact that we “choose” to store it as palmitic acid seems to suggest that it’s not the dangerous toxin we’ve been led to believe it is.

Hi Mark,

I have a weird problem :) I tend to be a very fast eater (speed at which I eat). As a result, even though I stick to primal foods, I tend to overeat by the time my appetite is satisfied.

I am sure there would be a few others like me who tend to have this problem. Would you have any tips on how one could slow down the speed of eating? It sounds like a simple problem – but just like any other bad habits, fast eaters have built it over a lifetime which makes changes difficult.

Appreciate your response. Thank you for all the great work you do that helps millions of people worldwide :)



Eating speed is absolutely a factor in health. To date, most of the research has focused on the links between eating speed and obesity, with fast eating being associated with higher body weight in middle aged womenmiddle aged men, and teenagers.

There’s evidence the link is causal. One study followed fast eating school age girls from fourth to seventh grade. Those who speed ate in fourth grade and continued to eat quickly through seventh grade gained the most weight, body fat, waist size, and waist-to-height ratio. Those who ate quickly in fourth grade but slowed down in the ensuing years had normal weight measures. Another study found that retraining fast-eating obese adolescents to eat more slowly improved their satiety responses to carbohydrates and reduced body weight.

That’s the big one, as you’ve noticed, Abhi: eating so fast that you outpace your own satiety signaling. Fast eaters tend to overeat, showing less satisfaction with their food despite eating way more of it.

Relationships between fasting eating and type 2 diabetes have also been found, even when adjusting for family history of diabetes, BMI, waist circumference, and activity level.

What can you do? Well, “don’t eat so fast” is obvious but mostly unhelpful advice. What are some more concrete tips a fast eater can try?

Eat with others. When you sit down (or stand) to a meal with friends, business associates, significant others, kids, or any other sentient being capable of engaging in conversation, you have something else to focus on – the other person.

Eat food that requires work. I enjoy a good amorphous multicolored mash of six different ingredients as much as anyone, but food like that lends itself to speed eating. Favor foods that require some cutting. Think meat on the bonewhole steakschops, and the like. Try to limit foods you can eat with a spoon, in other words.

Eat at the table. Your body needs to “know” you’re eating a meal, and that means sitting down at a table with actual plates, silverware, and even companions. If you’re driving while eating, standing in front of the open fridge digging through tupperware to snack, or grabbing a “bite” while “on the run,” you’re not creating the meal environment your body needs.

Eat when hungry, not when ravenous. You want to spice your food up with a dash of hunger, not dump the entire jar onto your plate.

Don’t eat in front of the TV. You’ll zone out and mindlessly shovel food into your mouth at breakneck speed.

Chew more. The more you chew, the more time each bite spends in your mouth, the slower you eat. Plus, there’s the possibility that better-chewed food will get digested more quickly and register in your brain as having been eaten sooner than partially chewed food. Some research points at 35 chews per bite (compared to 10 chews per) as optimal for reducing food intake, extending meal time, and increasing satiety.

Put the fork down in between bites. If you’ve got a fork in your hand all the time, of course you’re going to use it. So keep it out of your hand until it’s absolutely needed.

Practice mindful eating. Savor every bite. Observe the flavors and textures. Pinpoint individual ingredients. Consider absolutely everything about each piece of food entering your mouth, and ruminate deeply on your observations. I’m sure most of you will find satisfying all these practices somewhat exhausting, but being even a bit more mindful will slow you down.

Buy a Vibrafork. I poked fun at them last week, but they actually do exist.

Good luck!

That’s it for today, folks. Thanks for reading!

Read more:


The cholesterol-raising effect of dietary saturated fatty acids is largely accounted for by lauric, myristic, and palmitic acids. Dairy fat is a major source of myristic acid, and palm oil is especially rich in palmitic acid. Myristic acid is suspected of being much more cholesterolemic than palmitic acid, but direct comparisons have been lacking. We therefore fed 36 women and 23 men three diets that differed from each other in palmitic, oleic, and myristic acid content by about 10% of total energy. We used palm oil, high-oleic acid sunflower oil, and a specially produced high-myristic acid fat to achieve these differences. Each diet was consumed for 3 weeks in random order. Mean serum cholesterol was 4.53 mmol/L on the high-oleic acid diet, 4.96 mmol/L on the palmitic acid diet, and 5.19 mmol/L on the myristic acid diet (P < .0001 for all comparisons). Myristic acid raised low-density lipoprotein (LDL) cholesterol by 0.11 mmol/L, high-density lipoprotein (HDL) cholesterol by 0.12 mmol/L, and apolipoprotein (apo) A-I by 7.2 mg/dL relative to palmitic acid; increases relative to oleic acid were 0.50 mmol/L for LDL cholesterol, 0.15 mmol/L for HDL cholesterol, 6.0 mg/dL for apoB, and 8.9 mg/dL for apoA-I (P < .01 for all comparisons). The HDL cholesterol and apoA-I levels on the palmitic and oleic acid diets were the same. None of the responses differed significantly between woman and men. Myristic acid and palmitic acid both caused high LDL cholesterol and apoB levels and low HDL to LDL ratios.(ABSTRACT TRUNCATED AT 250 WORDS)