Nuts and seeds…Too much of a good thing?

For years, nuts and seeds were a BIG part of my diet.  Nuts, seeds, nut and seed bars, and nut butters were staples when it came to my everyday food plan.   I ate almond butter in my oatmeal in the morning, a bag of nuts for a snack, a few nuts on my salad for lunch and a scoop of peanut butter in my protein shake later on in the day.  Nuts and seeds, seeds and nuts…how could you lose with such a tasty nutritious snack?

The only problem, were some digestive issues: stomach bloating and seeing the undigested nuts and seeds in my stool (I know…too much information).  Quite honestly, I didn’t think much about any of these things because I knew how healthy they were for me. I thought of nuts and seeds as a good source of protein, filled with anti-oxidants, vitamins and minerals…plus they were convenient and tasted great… right?

These days, almost every-health conscious person loves their nuts and seeds.   Almonds, peanuts, cashews, pistachios, pumpkin seeds, sunflower seeds, and walnuts… these crunchy, tasty snacks go great with any salad, casserole or just eaten by themselves as a snack.  Eating nuts and seeds has become a staple for individuals who want a healthy snack, that’s easy and taste great.

BUT — (you knew there was going to be a BUT)—have any of you, like me, ever had digestive upset, bloating or undigested nuts and seeds in your stool?  I’ll guess most of you will say “yes,” and for those of you that said “no”, you may want to take a second look. Have you ever wondered why the nuts and seeds are in your stool?  No?  Well, the good news is I did…and this is why I am now asking:

“Are nuts and seeds as healthy for us as we all have been lead to believe? Could we actually be damaging our metabolism eating them everyday of our lives?  Are we over-nutting and over-seeding and causing digestive distress?”

Keep reading and you will find out…

First, lets look at the positive qualities of nuts and seeds.

* Nuts and seeds contain a moderate level of protein (anywhere from 5%-30% of their total calories)

* Nuts and seeds contain the so-called “healthy” fats

* Nuts and seeds contain anti-oxidants and other mineral and vitamins including:  selenium, calcium, magnesium, iron, potassium, phosphorus, folic acid and vitamin E.

* Nuts and seeds contain fiber

* Nuts and seeds are easy and convenient to eat when you are on the go

* Nuts and seeds taste great and go well with many dishes

So far, this all looks pretty good…right?  So, what possibly could be wrong with consuming nuts and seeds on a daily basis?

Here are 6 reasons you may want to re-think your nut and seed intake

  1. High levels of the wrong fats

So many people believe nuts and seeds are a great source of protein, which in truth, they are anywhere from only 5% to 30% protein.  Most nuts and seeds are somewhere in between.  The rest of the nuts and seeds calories come from fat.  Now, if you have been reading my blogs you will know I am not against eating fat.   BUT, I am against the anti-metabolic polyunsaturated fats (PUFA’s).  PUFA’s are commonly found in soy, corn, legumes, AND nuts and seeds.  The PUFA’s in nuts and seeds are actually used as protection toward hungry animals and from the cold winter weather.  However, what is protective to the seed has been shown to be toxic to the human.

According to Dr. Ray Peat

“Polyunsaturated oils defend the seeds from the animals that would eat them, the oils block the digestive enzymes in the animals’ stomachs. In addition, seeds and nuts are designed to germinate in early spring, so their energy stores must be accessible when the temperatures are cool, and they normally don’t have to remain viable through the hot summer months. Unsaturated oils are liquid when they are cold, and this is necessary for any organism that lives at low temperatures. These oils easily get rancid (spontaneously oxidizing) when they are warm and exposed to oxygen. When the oils are stored in our tissues, they are much warmer, and more directly exposed to oxygen, than they would be in the seeds, and so their tendency to oxidize is very great. These oxidative processes can damage enzymes and other parts of cells, and especially their ability to produce energy (cellular respiration).”

Like Dr. Peat states PUFA’s are highly oxidative, especially under heat and in the presence of oxygen.   This can cause decreased cellular function, leading to disease, aging and a slower metabolism.  If you want to understand the dangers of PUFA’s more refer to my blog, PUFA’s essential or toxic?

  1. Phytates or phytic acid

If you read my article on soy, you would already have some understanding of the negative effects of phytates.  Phytates are anti-nutrients that can block the absorption of important minerals like iron, calcium, magnesium, and zinc.  Phytates are usually located in the hard outer shell of the seed and nut referred to as the hull.  Phytates have a strong affinity for minerals, and any mineral it binds to will become insoluble. This is how phytates leaches nutrients from the body.

Phytates are not only found in nuts and seeds but also in grains, soy, beans and legumes.  I think it is important to understand that phytate rich foods may not only inhibit the nutrients within the food itself but also in the foods eaten with the phytate containing food.   Meaning the phytates in your nuts and fruit snack or your salad and nut meal will not only block the nutrients contained in the nuts but also the nutrients in the fruit and salad.

  1. Trypsin Inhibitors

Nuts and seeds, like soy, contain trypsin inhibitors.  Trypsin inhibitors, like phytates, are anti-nutrients.  Their function is to protect the seeds of plants from insects by blocking enzyme function. Just another protective mechanism mother nature has given seeds and nuts. These trypsin inhibitors prevent protease enzymes from digesting protein in the human digestive tract.  Therefore, the little bit of protein you may think you are getting from your nuts and seeds may not even be digested.

  1. Cooked nuts and seeds

Now, there is good news and bad news to cooking your nuts and seeds.  The good news is cooking your nuts and seeds can decrease the effects of phytates and trypsin inhibitors.  Cooking the nut and seed allows the fibers to break down and allows for easier digestibility.  The bad news comes in how the nut and seek are cooked.  Most nuts and seeds are “roasted”.  This usually means they were fried and cooked in more vegetable oil, adding insult to injury in the amount of PUFA you are about to ingest.  Some nuts and seeds are dry-roasted, which is better, but unfortunately still damaging to the nut or seed.  In a 2008 study published in the Journal of Agricultural Food Chemistry, nuts and seeds that were roasted had a higher degree of fat oxidation and increased levels of trans-fats.  Research also shows that roasting nuts and seeds at high temperatures denatures the protein.  The denatured protein loses it structure and can become harder to digest.

  1. Raw nuts and seeds.

Many health conscious people think they are winning the battle over nuts and seeds by eating them raw.  Quite honestly, I use to be one of those people.  However, with further investigation I now believe eating raw nuts may be worse than eating the dry-roasted ones.  Why?  Well, mostly for the reasons I have already explained. Raw nuts are filled with phytates and trypsin inhibitors.  Raw nuts are almost indigestible by the human body.  They can cause irritation in the gut and small intestine by getting “stuck” in the intestinal micro-filli; this can cause inflammation, bacterial over growth, bloating, and gas.  I cannot even tell you how many health conscious people I meet complaining of digestive upset.   Nut ands seeds may be the sole culprit, or there could be a number of contributing factors– grains, fibrous vegetables and fruits, cheap dairy, carrageenan, processed foods, additives, grain-fed meats, PUFAs, endotoxins, and bacterial overgrowth all seem to play a role in digestive upset.

  1. Non-organic nuts and seeds.

If you are a nut and seed-eater, you know they are not a cheap food.  Nuts and seeds can be costly and if you go organic they can cost you upwards of $25.00/lb.  Most clients I work with are eating the raw or roasted non-organic varieties.  The problem is they may also be consuming pesticides and herbicides that are concentrated in the oils (fats) of the nuts and seeds.  The fats in seeds and nuts have a high affinity to attracting toxic pesticides.  Organic nuts and seeds are usually, but not always, free of toxic pesticides.

Ok, so what have we learned?  Maybe the handful of raw nuts and seeds you have been gobbling down everyday is not as healthful as you thought.  Maybe, just maybe, you might need to rethink your nut and seed consumption.

Personally, I am no longer a nut and seed-eater.  Or should I say a daily nut and seedeater.  My consumption has gone from a few handfuls a day to maybe a few handfuls a month.  If I do consume nuts and seeds I try and follow some simple guidelines.

  1. Soaked and/or sprouted are best.  


  1. Go Organic.  
  1. Some nuts are better than others.
  1. Eat in moderation.

Have I managed to make your head hurt yet?  Although it is never my intention to make people confused about what they are eating, I know it may sometimes occur.  Yet, I do believe we learn and grow as soon as we become confused.  So if I have confused you–then good—you are learning something.

Honestly, my only true intention is to share with you what I am learning and how it is working/not working for my clients and me.  It’s certainly not up to me to tell you what to do.  I am only here to help educate you and help you THINK before you grab that next bag of nuts.

I think it is important to remember that there are no clear-cut routes when it comes to nutrition and how it can affect YOUR health.  I think we should all be open to learning the good, the bad and the ugly when it comes to eating certain foods.  We are all different, at different phases of life, and have different health issues and needs.  The more you learn, the more you understand the more you can improve yourself and your diet.

Your Optimal Health Coach,


“Disclaimer:  I am an exercise physiologist, personal trainer, nutritional and lifestyle coach, not a medical doctor.  I do not diagnose, prescribe for, treat or claim to prevent, mitigate or cure any human disease or physical problem. I do not provide diagnosis, care treatment or rehabilitation of individuals, nor apply medical, mental health or human development principles.  I do not prescribe prescription drugs nor do I tell you to discontinue them.  I provide physical and dietary suggestions to improve health and wellness and to nourish and support normal function and structure of the body.  If you suspect any disease please consult your physician.”


  1. Rita Yaacoub, Rachad Saliba, Bilal Nsouli, Gaby Khalaf and Inès Birlouez-Aragon.  Formation of Lipid Oxidation and Isomerization Products during Processing of Nuts and Sesame Seeds.  J. Agric. Food Chem., 2008, 56 (16), pp 7082–7090
  2. Thomas Richardson, John W. Finley.  Chemical Changes in Food During Processing.  Pg 206-209
  3. Pelvan E, Alasalvar C, Uzman SJ Agric. Effects of roasting on the antioxidant status and phenolic profiles of commercial Turkish hazelnut varieties Food Chem. 2012 Feb 8;60(5):1218-23. Epub 2012 Jan 27.
  4. EUFIC REVIEW 11/2010   “The Why, How and Consequences of cooking our food”
  5. Bohn T, Davidsson L, Walczyk T, Hurrell RF. “Phytic acid added to white-wheat bread inhibits fractional apparent magnesium absorption in humans.” The American Journal of Clinical Nutrition. 2004. 79(3):418-423.
  6. Mahgoub SEO, Elhag SA. “Effect of milling, soaking, malting, heat-treatment and fermentation on phytate level of four Sudanese sorghum cultivars.” Food Chemistry. 1998. 61(1-2):77-80.
  7. Macfarlane BJ, Bezwoda WR, Bothwell TH, Baynes RD, Bothwell JE, MacPhail AP, Lamparelli RD, Mayet F. “Inhibitory effect of nuts on iron absorption.” The American Journal of Clinical Nutrition. 1988. 47:270-274.
  8. Fanbin Kong1 and R. Paul Singh.  Food Biophys. Digestion of Raw and Roasted Almonds in Simulated Gastric Environment.  2009 December; 4(4): 365–377.
  9. Pandey P, Raizada RB, Srivastava LP.  Level of organochlorine pesticide residues in dry fruit nuts.  J Environ Biol. 2010 Sep;31(5):705-7.
  10. Ricardo Bessin, Gerald R. Brown, John R. Hartman, and James R. Martin  FOOD SAFETY:  PESTICIDE RESIDUES IN GRAINS, VEGETABLES, FRUITS AND NUTS.   ISSUED: 7-90
  11. Allard JP, Kurian R, Aghdassi E, Muggli R, Royall D.  Lipid peroxidation during n-3 fatty acid and vitamin E supplementation in humans.  Lipids. 1997 May;32(5):535-41.
  12. Meydani M, Natiello F, Goldin B, Free N, Woods M, Schaefer E, Blumberg JB, Gorbach SL.  Effect of long-term fish oil supplementation on vitamin E status and lipid peroxidation in women.  J Nutr. 1991 Apr;121(4):484-91.
  13. Gonzalez MJ, Gray JI, Schemmel RA, Dugan L Jr, Welsch CW.  Lipid peroxidation products are elevated in fish oil diets even in the presence of added antioxidants.  J Nutr. 1992 Nov;122(11):2190-5.
  14. Humphries KM, Yoo Y, Szweda LI.  Inhibition of NADH-linked mitochondrial respiration by 4-hydroxy-2-nonenal. Biochemistry. 1998 Jan 13;37(2):552-7.
  15. Dr. Decuypere’s Nutrient Charts™
~~ Nuts, Grains & Seeds Chart .

  1. Dr. Ray Peat.  ”Unsaturated Vegetable Oils: Toxic”