Nuts have gotten a surprising amount of flack as of late. Many nuts have a fairly high PUFA content, and most of that PUFA is omega-6 linoleic acid, the same one we try to avoid by avoiding seed oils. Linoleic acid is easily oxidized, accumulates in our tissues and determines our inflammatory response, is highly unstable for cooking, usually rancid on the shelf, and, thanks to government farm subsidies and public hysteria over animal fat, it’s in absolutely everything nowadays. We Primal types generally avoid it for good reason, and that tends to influence how we perceive the O6 content of nuts.
Is there a place for nuts in the Primal Blueprint diet? Should we worry about nuts and omega-6 fats? Let’s take a closer look.
How Much Omega-6 Do Nuts Contain?
In a typical serving of each:
Walnuts – 9.5 g
Almonds – 4.36 g
Cashews – 2.6 g
Macadamias – 0.5 g
Brazil nuts – 7.2 g
Hazelnuts – 2.7 g
Pistachio – 4.1 g
Pine nuts – 11.6 g
Pecans – 5.8 g
A diet high in most nuts, then, would presumably skew the vaunted tissue omega-6 to omega-3 ratio toward pro-inflammatory bodily processes… right? I mean, if you were to eat food fried in high-O6 vegetable oil at some restaurant, that would be pro-inflammatory. If you were to eat cheap Chinese food stir-fried in cheap, high-O6 soybean oil every day for lunch, you’d expect a good amount of oxidized LDL at your next lipid test. And if you were to supplement your diet with a few daily tablespoons of unheated corn oil, there would be markedly negative effects (besides gagging and/or vomiting) on your body. How are nuts any different?
Nuts are Whole Foods
For one, nuts aren’t just “bags of linoleic acid.” A nut is a pretty complete nutritional source. After all, it’s the seed of a tree, a sort of arboreal egg. Contained within is everything that tree needs to start growing from scratch—fats, carbohydrates, even protein, plus natural antioxidants like Vitamin E and plenty of minerals.
Consider 160 calories worth of raw almonds, which has 3.5 grams of omega-6 linoleic acid. What else do you get along with those PUFAs?
76 mg of calcium
76 mg of magnesium
207 mg of potassium
0.3 mg of copper (a third of your RDI)
0.9 mg of zinc
25% of your daily riboflavin
45% of your daily vitamin E
Prebiotic fiber to feed your gut
Not bad, right? Nuts aren’t just defined by their omega-6 content.
Compare that to 160 calories worth of soybean oil, which has almost 10 grams of linoleic acid. What else do you get along with those PUFAs?
You don’t get any vitamins or minerals to contribute toward your micronutrient status. You don’t get any vitamin E to protect the fragile omega-6 fats from breaking down. You get absolutely nothing.
Even if the omega-6 fats in nuts are bad taken in isolation, the positives of the nut seem to outweigh them. Whole nut intake seems to reduce markers of systemic inflammation, and inflammation is linked with a wide range of ailments and afflictions (obesity, insulin resistance, heart disease, excess cortisol, etc.). To isolate and praise or malign a single component of nuts is wrong without considering them as complex food matrices containing diverse nutrients and other chemical constituents. In other words, nuts are food, not single nutrients.
Pick a nut, any nut, and you’ll find research showing benefits from its consumption.
Nutritional Value of Nuts
If the high omega-6 content of nuts was such an issue, you’d probably see an indication in the literature. Instead, the vast majority of studies find only benefits to nut consumption.
Walnuts improve lipid profile, lower oxidative stress, increase cholesterol efflux, and improve cardiovascular disease risk.
Pistachios attenuate the glucose response to carb-rich meals.
Pecans acutely increase antioxidant capacity and lower LDL oxidation.
Hazelnuts reduce the susceptibility of LDL to oxidation.
Brazil nuts improve selenium status, glutathione activity, and lower inflammation.
When the Omega-6 in Nuts Can be Too Much
Problems arise with steady year-round access to foods whose historical availability was seasonal and intermittent. If you were a hunter-gatherer, you probably weren’t gathering bushels of nuts on a daily basis – at least, you weren’t finding enough nuts in the wild to eat eight ounces a day. Nuts are seasonal in the wild. Perhaps the best example of a traditional hunter-gatherer population eating significant amounts of nuts are the Hadza of Tanzania, who eat large amounts of mongongo nuts only when they’re in season. They can’t go down to the corner store for a sack of out-of-season nuts, and nor could any human for most of our history.
Model your nut consumption after biologically-appropriate, evolutionarily-congruent availability patterns and you will be fine.
Eating a handful of almonds and Brazil nuts won’t give you too many omega-6 fats.
Eating half a bag of almonds and Brazil nuts will.
It’s all about the quantity.
Nuts should never comprise the bulk of your diet, anyway. A quarter cup as a snack every now and then isn’t going to kill you. It’s not even going to compromise your progress. I mean, they’re nuts. They aren’t meals, and they’re not meant to be. They’re snacks, basic supplements to an already nutritious diet replete in animal fat, protein, and vegetables. And in a diet like the Primal Blueprint that provides plenty of omega-3s through seafood to balance out the omega-6, nuts definitely have a place.
Just make sure you treat your nuts as delicious treats, rather than staple cornerstones of a meal. Don’t burn your nuts, and don’t cook with the oil. The safest bet is to buy them raw and soak or roast them yourself. That way, you control the heat and you can mediate the oxidation.
Overanalyzing your food intake is a good way to stress yourself out and make every little dietary choice an internal struggle. Avoid falling into this trap. Be vigilant of your food choices, but pick your battles wisely. Making sure you ask the waiter to cook your omelet in butter rather than vegetable oil is worth the trouble; stressing over the Omega-6 content of the twenty walnuts in front of you is decidedly not.
Care to weigh in with your thoughts on nuts? I know a lot of forum members have reservations about them, so I’d love to hear in the comments section.