Since there’s less than 0.02% separating us genetically, it shouldn’t come as a surprise that our optimal nutrition strategy is closely related to the eating habits of hunter-gatherers. Unfortunately, one of the major differences today is that foods that were scarce then, are easily attainable now. With nuts and seeds being a prime example.
I’ve been eating predominantly like a hunter-gatherer for the last 15 years and I can’t tell you the number of times I was saved by my nuts. However, similar to the nuts you’re now laughing about, reaching for them too often can get you in trouble…and it’s not because of fat and calories!
Nuts Are High in Phytic Acid
The first challenge with nuts is that they have some of the highest phytic acid levels (in mg per 100g of dry weight):
- Brazil Nuts – 1719mg
- Almonds – 1138-1400mg
- Walnuts – 982mg
- Hazelnuts – 648-1000m
To put that into perspective, oats are at 1175mg, brown rice 990mg, refried beans 642mg, and corn 367mg.
Phytic acid reduces nutrient absorption (magnesium, calcium, iron, zinc, and B12), and can inhibit digestive enzymes like amylase (to properly breakdown carbohydrates), and pepsin (to digest proteins). Although it only becomes an issue when consumed in above average amounts, each additional milligram produces a considerable decrease in absorption.
Zinc absorption decreases by 18% for 2mg of phytic acid, 64% from 25mg, and 82% from 250mg.
Fortunately, this tends to be more of a concern for those refraining from meat, as they tend to rely heavily on high-phytic foods as their main protein sources (beans, legumes, nuts and seeds). Many are consuming some source of phytic acid at every meal, and usually in much larger quantities.
Common sense says we’ll eat more 100g servings of brown rice (1 cup = 150-250g) than 100g servings of brazil nuts; but unfortunately, that’s not always the case. The convenience of nuts and seeds, and prioritization of them as snacks for those following a Paleolithic eating strategy, makes them commonly overconsumed
Although we could attempt to soak nuts and seeds to reduce their phytic acid content, research suggests that an 18hr soak only removes 50%. The bigger question is, who’s actually going to take the time to do this?
I’ve developed my philosophies over the years based on what I believe is realistic and necessary. If I’m not going to soak my nuts, then my clients won’t soak their nuts, and probably you won’t either.
Plus, I heard its not good for sperm quality (joking!)
Nuts Are High in Omega-6 PUFAs
The 2nd reason for controlling our intake of nuts and seeds, is because of the amount of omega-6 polyunsaturated fatty-acids (PUFAs):
- Pine Nuts – 11.6g
- Walnuts – 9.5 g
- Brazil Nuts – 7.2 g
- Pecans – 5.8 g
- Almonds – 4.36 g
- Pistachio – 4.1 g
- Hazelnuts – 2.7 g
- Cashews – 2.6 g
- Macadamias – 0.5 g
Fortunately, nuts and seeds are not the isolated omega-6 PUFAs, like the oils discussed here. The PUFA from a nut or seed in its whole natural form is not going to be as highly reactive, and it comes packaged with high amounts of built-in antioxidants. Interestingly, the whole reason nuts and seeds have phytic acid is to protect themselves from oxidation.
That being said, we should keep a close eye on our nut and seed intake to control our omega 6:3 ratio. A disjointed ratio in favor of omega-6’s promotes chronic inflammation; and unfortunately, the cheap oils (soybean, sunflower, canola) used in commercial products, restaurants, and animal feed is already facilitating a higher than acceptable ratio. Most North Americans are looking at an omega 6:3 ratio of 25:1, instead of the 1:1 our Paleolithic ancestors enjoyed.
Nuts Are a Garnish NOT a Meal
Nuts and seeds aren’t a huge deal in small quantities, here and there (to garnish), but chop up 100 almonds into a flour and throw them in the oven at 300F and you’re stirring up trouble. Not only does the heat increase the risk of oxidation, but any phytase present in these foods (to help digest phytic acid) is destroyed at 176 degrees Fahrenheit in 10 minutes.
Nut Flours = Too much phytic acid + No ability to digest it (phytase)
If you’d rather eat almond flour cookies on your Feast (or Cheat) Day, as opposed to wheat flour, then go for it (I will encourage that). However, it would be a travesty if you take the advice to eat like a Caveman and start making almond flour muffins everyday for breakfast. One of those will give you 700mg of phytic acid, plus a boatload of oxidized PUFAs. Throw in 50 grams of cocoa powder and you’ve got another 800mg.
Interestingly, a study from Oxford University demonstrated the negative effects of overdoing a food that would otherwise be considered healthy. I mention this research because many following an ancestral or hunter-gatherer diet over-do the nuts and seeds to avoid giving up baked goods, and breads. Published in 2014, results from the analysis of 52 skeletons from a 15, 000 year old hunter-gatherer tribe in Morocco, showed a considerable amount of tooth decay. The lead researcher, Dr. Louise Humphrey, suggested that a heavy reliance on edible acorns as a dietary staple could be the catalyst.
“The acorns may have been boiled or ground to make flour; cooking the acorns would have added to their stickiness, and abrasive particles from grindstones contributed to rapid tooth wear so that cavities started to form on the roots of the teeth.”
Many following a Paleo eating strategy are correct in believing that the degenerative disease and ailments plaguing human beings was initiated by the agricultural revolution. However, this doesn’t mean they can’t over-eat a food on the ‘approved list.’ If you Make Meat Mandatory, there should be no reason to rely on nuts and seeds as a dietary staple.
Hunter-gatherers didn’t have 2lb bags of nuts from Costco at their finger-tips 24/7. They’d stop and pick a few nuts, seeds and berries while on a hunt for ANIMAL PROTEIN!
Nuts & Seeds – Best Practices
Despite the negatives of eating too many, nuts and seeds play an integral part of a healthy diet. They contain a considerable amount of protein and fat (45-75%), that provides fuel for your brain and support for your body. Although walnuts appear to be the best choice with respect to antioxidant and omega-3 levels, research has shown that a wide-variety of nuts (pecans, pistachios, almonds, hazelnuts, macadamias, pine, brazil) produce considerable reductions in oxidative stress and inflammation.
Eating a 1-ouce serving of nuts 5 days a week instead of 1, lowered heart disease risk by 50%
There also appears to be an inverse relationship between nut and seed intake and body fat, with several studies finding that:
Individuals eating nuts and seeds regularly were less likely to be obese and were at a lower risk of becoming obese.
Other than keeping on eye on your daily intake, here are 9 best practices to get the most out of nuts and seeds:
Prioritize Nuts & Seeds with Best 6:3 Ratio