Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
17 May

How Bad is Peanut Butter, Really?

Man, you guys really love your peanut butter.

I get at least one email a week from a devoted reader of the blog who just can’t shake the desire (that feels like a need) to eat peanut butter on a regular basis. They’re on board with everything else. They’ve ditched grains and vegetable oils. They’re walking more and getting better sleep. They’re getting sun and eating more vegetables than ever before. They’ve switched to grass-fed beef (sometimes liver, too!) and wild-caught fish. They’ve even happily dumped all the other legumes, except for that persistent, palatable peanut. The more dedicated among them may be soaking, sprouting, roasting, and grinding their own peanuts into peanut butter, but they’re still eating peanut butter – a “forbidden” food on the Primal eating plan.

I’m talking questions like this:

Dear Mark,

I have been following MDA for about a year now and last I week I finally went primal.  So far I have not had any issues with giving up grains (no cravings), except I cannot shake my peanut butter addiction! I eat a small bowl full of peanut butter with banana slices for a snack and I know it is awful for me! I eat very healthy foods for the rest of the day (eggs for breakfast, salad for lunch, meat and veggies for dinner) but the peanut butter is probably preventing progress! Help!


I don’t want people to feel deprived, nor do I enjoy stripping from them the ability to enjoy their favorite foods, but I also want people to make the best and healthiest food choices possible. To do that, we need to examine the evidence. We need to give peanut butter the rice and oat treatment. We need to figure out whether or not peanut butter is really all that bad. Let’s go, shall we?

First, The Good.

What’s good about peanut butter? Why would we ever want to eat it?

It’s tasty.

I’ll admit it: peanut butter is quite delicious. I’ve never much cared for actual peanuts – they were okay, but not something I sought out – but I’d always grab a spoon or dip a finger for some peanut butter.

It contains nutrients.

It’s food, so of course it has something to it. But what?

Peanut butter is a decent source of thiamin, niacin, folate, and magnesium. It’s actually fairly rich in polyphenols, particularly when roasted (which increases the coumaric acid content considerably). Peanuts also contain small amounts of CoQ10 and resveratrol, though I’d much rather get those from beef heart, sardines, and red wine, personally.

Now, The Bad.

Why should we avoid it? What’s not to like about peanut butter? I’m not even going to discuss the soybean oil and sugar-laden garbage that passes for peanut butter, because my readers definitely aren’t asking about that stuff. They’re doing natural butter with peanuts (and salt) as likely the only ingredient.

It generally contains aflatoxins.

Aflatoxins are naturally occurring fungal toxins, or mycotoxins, produced by certain members of Aspergillus, a type of fungus found pretty much everywhere throughout the world. Aspergillus tends to colonize any monosaccharide and polysaccharide it comes across, as long as the conditions are right, but peanuts are particularly susceptible. Most crops are colonized after harvest and during storage, but since Aspergillus is found in the soil (among other places) and peanuts grow underground, peanut colonization often occurs well before harvest. The result is that peanuts are among the most contaminated crops, along with corn and cottonseed.

I wrote about the negative effects in a previous post, which I’ll sum up for you:

Aflatoxin, being a toxin, is metabolized by the liver. Large enough doses of aflatoxin are a liver carcinogen in high doses (it’s actually what T. Colin Campbell used to induce liver cancer in mice during his China Study crusade to indict animal protein). Early exposure and elevated bloods level of aflatoxin are associated with stunted growth in children.

Interestingly, it seems that the peanut butter-making process dramatically reduces the aflatoxin content of the initial peanuts, by around 89% (PDF). In the study, roasting at 160 degrees C reduced aflatoxin by 51%. Blanching, or skin removal, reduced it by 27%. Finally, grinding the peanuts into butter removed another 11% of the aflatoxin, probably because of the heat (not the actual grinding). So if you’re going to eat peanuts, stick with a good butter.

It contains peanut agglutinin.

As of now, the harmful effects of peanut agglutinin, a peanut lectin, are mostly speculative, but still compelling:

  • In isolated human colon cancer cells, peanut lectin is a mitogen, or growth-promoter. You generally don’t want cancer cells to divide and increase in number.
  • Altered glycosylation may be at the heart of inflammatory bowel disease-related cancers, like colon cancer.
  • Peanut agglutinin causes colon cancer cell proliferation via altered glycosylation, in an in vitro study.

That said, those are just in vitro studies. They don’t tell us what happens when peanuts are eaten. However, in real live human subjects who ate real peanuts, peanut agglutinin has been shown to make it through the gut lining to end up in the blood stream. That’s a little worrisome, don’t you think?

I want to reiterate, though: eating peanut butter has never been causally linked to the development of colon cancer. In fact, one epidemiological study found that frequent intake of peanuts and peanut products was linked to a lowered incidence of colorectal cancer in Taiwanese women.

It might contain a uniquely atherogenic oil. 

Yeah, peanut oil has a good amount of monounsaturated fat, about 46.8% of the total fatty acid content, which has earned it a solid reputation for heart health in the conventional health world. But it’s also got a significant amount of PUFAs, too. 33% of the total fat is omega-6 linoleic acid, with an essentially nonexistent omega-3 ALA content. You could say that about a lot of nuts, though, and I don’t think the PUFA content is the big determinant here. It doesn’t help, but it’s not a deal breaker on its own. Let’s dig a little deeper.

Peanut oil has favorable effects on standard lipid panels. LDL drops, total drops, total:HDL ratio drops. The jury is out on how much that all matters, but eating peanut oil will probably make your cardiologist happy. Awesome, right? Maybe, but peanut fat appears to be uniquely atherogenic despite the lipid effects. For decades, it’s been used by scientists to induce atherosclerosis in cholesterol-fed rats, rabbits, and primates. Some researchers think that peanut lectins, present in the oil, are the cause of the atherogenicity. Reduction of the lectin content of peanut oil, through “vigorous washing,” also reduces the atherosclerosis it causes (although not completely).

You know what else reduces the peanut lectin content? Not eating any peanut butter.

It’s a little too tasty.

There’s something about the combination of fat, salt, protein, and smooth scoopability of peanut butter that promotes overeating. I wasn’t able to bring up any concrete studies on the pro-bingeing effects of peanut butter in humans (though if you run a Google search for “peanut butter addiction,” you’ll get a bevy of testimonials from all sorts of people claiming to be addicted to the stuff), I believe it. And I bet obesity researchers who typically work with rodents would believe it, too, since peanut butter is often used in these studies as a high-reward, obesogenic comfort food that rats and mice will readily and consistently overeat.

Ultimately, to feverishly scoop in a ravenous frenzy or not to feverishly scoop in a ravenous frenzy is a choice you have to make. I wouldn’t recommend eating peanut butter very regularly, and I know I won’t for the reasons mentioned above, but that doesn’t mean you have to follow suit. The inclusion – or exclusion – of peanut butter (or peanuts in general) will not make or break your Primal cred. There are a lot of things you want to have under control before obsessing over peanut butter, like grains, omega-6 oils, sleep, exercise, play, daily low level activity level, quality of meat, etc. You get those under control and then start thinking about some peanut butter as a treat every now and then, if ever.

As I see it, the easy answer is to just not eat it, because I don’t see anything at which it particularly excels (besides inducing people to eat the entire jar in a single sitting). You can get your polyphenols and your minerals from fruits and vegetables, your monounsaturated fat from meat, olive oilmac nuts, and avocados, and your smooth pulverized salty nutty fix from almond butter, mac nut butter, coconut butter, or any other nut butter – without the peanut lectin, the weirdly atherogenic fat, the aflatoxin load, or the insatiable desire to eat more and more and more until it’s all gone and your forearm is sticky.

Of course, it’s easy for me to say: I don’t have a peanut butter habit.

Anyway, let’s hear from you guys. Do you eat peanut butter? Are you addicted? Are you able to stop with just a bite or two? And most importantly, has your peanut butter habit negatively affected your results? Let me know in the comment section!

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. I think Barney Butter is the most incredible nut butter…it happens to be made from almonds, but tastes even better than peanut butter. Tastes like Skippy or Jiff. YUM!

    cz wrote on May 18th, 2012
  2. I’m not really a fan of peanut butter, and once I go natural style it is definitely more of an ingredient than something I would put on my toast.

    (I did used to take finger-fulls as a kid, but I think that was more sugar-calories-fuel-easy reward system than any sort of palate discrimination.)

    I think I have a total of three recipe types that use peanut butter; throw-the-packet-out ramen broth, oriental meat-marinades, and the other has a strong tomato component. I might be able to deal with my tomato-nut recipe using a different nut if it has a strong flavor, cheap price, and stores well. The ramen broth can go mustard-based no problem, and hopefully the nostalgia will eventually go away.

    Kelekona wrote on May 18th, 2012
  3. I was never big on peanut butter until I had the “real” stuff – no sugar, no salt, just peanuts. Wow! For me, almond butter is just OK and actually kind of ruins the taste of a good, healthy smoothie, whereas peanut butter enhances one.

    I did read a study several years ago that addressed how peanut butter and just the smell of buttered popcorn can influence women’s moods (think oysters as an aphrodisiac.)

    AmyC wrote on May 18th, 2012
  4. I never had the taste for peanuts and peanut butter. They were good as a treat depending how they were prepared. the thing I miss most is peanut sauce, but I found and excellent recipe for satay chicken with almond butter sauce that I like even better! Sure your ahead if you choose peanut butter over cake or twinkies, but if you really want to live optimally peanut butter is something you can cut out. I admit I’m speaking from an ex smoker’s point of view. Compared to quitting a 15 year cigarette addiction peanut butter is nothing. I also used to brew beer and go to tastings…..I will be giving up beer after Memorial day. What makes this easy for me is the remarkable changes in my attitude, energy, and general feeling of well being in the last month of moving in a primal direction. For the almond butter enthusiasts I really like the Kettle brand, natural almond butter. It even comes in a BPA free plastic jar!

    Ashley wrote on May 18th, 2012
  5. Thanks Mark, great post! My son was diagnosed with peanut allergy at the age of one but during a hospital managed ‘challenge’ at age two he seemed to have outgrown it. The advice from our immunologist was to expose him regularly to peanuts in some form to ensure the allergy does not reappear. So, my question Mark, is this: Given that he must have it, what is the best form, in your opinion? We are currently giving peanut butter made from roasted organic nuts, with no salt added. ari :)

    ari wrote on May 19th, 2012
  6. I never ate peanut butter regularly except briefly on the Zone in 1996. Read years ago that it contains lectins so avoided. Last year I discovered the Justin’s single packet nut butters and so decided to buy a pb packet to have as part of a Warrior meal and well…. sure, it’s tasty. I like the chocolate pb packets best. Fortunately hard to justify because the Justin’s brand uses palm oil which is bad. So, every once in a while I have a choccy pb packet, feeds my inner child.

    catrina wrote on May 19th, 2012
    • why is palm oil bad? i thought it was supposed to be good (lot’s of MCT).


      pam wrote on May 20th, 2012
  7. Eat what you like but consider with your eyes closed the ramifications it’s having on your insides and the things you can’t see.

    If you are feeling better when you aren’t eating and feeling hungover after you’ve eaten it. Most likely it’s not the best choice.

    But everyone has got to treat themselves. If you don’t you are doomed to failure. Remember it’s a “blue print” and even building schematics get changed during construction do to unseen obstacles. It takes time to change but you don’t stop because there is a wall! Push through and ditch the habits over time. Your body will thank you!

    Nicolas zahasky wrote on May 19th, 2012
  8. Great article. I think I eat way too much peanut butter. It’s also quite high in calories. Before you know it you have eaten hundreds of calories. Hopefully reading this information will cause me to eat less of it.

    Leighton wrote on May 19th, 2012
  9. I bought raw almond butter and its amazing! ! Way tastier than regular roasted almondbutter.

    Gabriel Wigington wrote on May 19th, 2012
  10. Grew up on the stuff but stopped eating it for a few years. I read about the lectins a few years ago and determined to go clean…but got crazy pregnancy cravings and gained a gazillion pounds from 2am indulging. The constant craving bugged me so I over-ate until I was sick of it….clean pantry again and I won’t consider buying it. There’s no such thing as just one bite.
    Next pregnancy: I’ll cope with nightime cravings with a tsp of cod liver oil and wash it down with raw milk, if it’s the right season. Or coconut oil and a hard boiled egg.

    Olivia wrote on May 19th, 2012
  11. I love peanut butter on apples…that’s the only time I eat it though, but fairly regularly so. I bought some almond butter, but just didn’t like it, and I don’t think my body did either, even though I can eat almonds just fine. It wasn’t organic, maybe that’s why. Maybe it would help to make my own nut butter, but I really don’t want to buy a food processor.

    In any case, I’ve only been primal for 2 weeks, figure I can ease in slowly for all the edge cases. I’m pretty committed in general to my good health. :)

    Cristina wrote on May 19th, 2012
  12. I used to love peanut butter but had to give it up even before going primal. Peanuts are very high in androgen hormones which is a problem for those who get acne breakouts. Whenever I would eat PB an acne breakout would always follow. So, I switched to almond butter and no problem. I use almond butter in primal recipes I make from, otherwise I just prefer eating whole almonds as a snack.

    Kelley wrote on May 20th, 2012
  13. I like peanut butter but have it rarely. Get the good stuff, only salt is added.

    What I do eat a lot of are “skin on” spanish peanuts. They are tasty and serve as a midnite snack. I prefer the spanish peanut form since the skin on the peanut is loaded w/ resveratrol and I don’t like red wine.

    Iluvatar wrote on May 20th, 2012
  14. What about tahini ? It’s made from sesame and I consider it quite healthy. It’s not extremely tasty, especially since I buy a non-roasted version, but when taken with something else, it’s acceptable.

    Rosenthal wrote on May 20th, 2012
  15. Mark, I think you forgot one more good thing about peanuts – but not commercial peanut butter – is their skins have the highest amount of proanthocyanidins than any other food source per dry weight.

    It has always leaved me to wonder, what does Jiffy do with all those glorious cranberry red coloured skins after they strip all their peanuts clean?

    Paul M. wrote on May 20th, 2012
  16. Try a mix of almonds, cashews and macadamia’s.
    Blend the almonds and cashews first then slowly add macadamia’s until you get you preferred consistency.

    Stuart wrote on May 20th, 2012
  17. Brazil, cashew and almond butter – a matc made in heaven

    Aussie123 wrote on May 21st, 2012
  18. Only found out recently that I’m only allergic to peanuts, rather than all nuts in general. Absolutely loving trying out all these new flavours. Favourite has to be pistachios and cashews. Yum!

    Aussie123 wrote on May 21st, 2012
  19. My family all transitioned to the TJ’s sunflower seed butter very easily. So, if you are not an almond butter fan (which I am not) you might find the sunflower seed butter more to your liking.

    Michael wrote on May 21st, 2012
  20. I like peanut butter, but I don’t have it very often. I only like the whole nuts if they are still in the shell (There is just something about having to work for it that makes them that much better) but I really prefer almonds or pistachios or cashews over peanuts.

    Beth wrote on May 21st, 2012
  21. how about powdered peanut butter from bell plantation or betty lous great stuff. it is organic Organic Peanuts, Organic Coconut Sugar*, Sea Salt. and only 4 grams carbs.

    capemayorganicmarket wrote on May 22nd, 2012
  22. I definitely was addicted to peanut butter, it’s so hard to stop eating once you start! I started buying individual packets instead of a jar which yes, is more expensive, but worth the forced portion control. The portion control of the packets really forced me to cut back and decrease my peanut butter binges. Over time I just stopped eating it and found that I didn’t miss it all. If your seriously addicted, give the packets a try.

    Lauren wrote on May 22nd, 2012
  23. I used to ADORE peanut butter. . .in fact, a PB&J was my preferred meal or snack any time of the day (or a bowl of rice chex, but I digress).

    Now, I’m perfectly happy with raw almond butter. . . but I’m still trying to get my kids to not pine after peanut butter. I just found a chocolate sunflower seed almond butter. . . it’s delicious, but does have sugar. :(

    Jamie wrote on May 22nd, 2012
  24. I never thought of it as an addiction until reading this. Just last week I sat down with half a jar of chunky and a spoon, it never stood a chance. I’m just starting to change my eating habits due to a long list of medical reasons. Thanks for the information

    Damion S wrote on May 22nd, 2012
  25. I’ll be honest here…I’m not giving up my peanut butter. I eat the best kind of peanut butter you can find and 1 or 2 tablespoons of it a day. I ccan do the no grains or dairy, but peanut butter is my breakfast every day with a scoop of a high quality protein powder. Most negative aspects of peanut butter are speculation and lack of self control. Peanuts are also very good for you despite what you wrote most of which is…speculation or due to people’s lack of self-control with the stuff making it no different then any other tasty food. I will continue enjoying the stuff. Sorry.

    Mindy1986 wrote on May 23rd, 2012
  26. Once again, Mark, great, thought-provoking post! I always enjoy reading your ideas, even if I don’t always totally agree – Peanut butter… we keep a jar of Teddie’s Brand on hand to load the mouse traps. And another jar to occasionally treat ourselves with. Thanks to all for great snack ideas…

    primalgranny wrote on May 23rd, 2012
  27. It could also be that your body is craving/needing a nutrient in the peanut butter, and not the peanut butter itself. : )

    Raymond wrote on May 23rd, 2012
  28. I guess no more nuts on my salad; maybe just a tablespoon of pine nuts.

    Kenny wrote on May 25th, 2012
  29. Oh my gosh! My kids eat so much peanut butter! Have I been stunting their growth!? ::Freakout::

    Alexis wrote on May 26th, 2012
    • Peanut butter is one of the staples of childhood food in America. So if your kids are stunted, then probably all American kids are stunted. Considering that we produce pretty much the biggest kids in the world, I think this is unlikely. Just keep them away from that sugary stuff like Jif and Peter Pan. In fact, if you want your kids to eat less peanut butter, just start buying the grind-to-order kind like what’s available at Whole Foods and other natural grocery stores. They’ll probably hate it, because it’s not smooth, sweet, and creamy like the industrially produced brands.

      MarkA wrote on July 20th, 2012

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