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Food Intolerances

by Jon Sasmor

Last Updated July 13, 2018

Food Intolerances Are Common and Often Missed

Many people have bad reactions to certain foods without realizing it. Why? People tend to eat the same foods frequently. Harmful effects can show up from minutes to 3 days later. It's hard to correlate what's happening right now with a snack you ate 3 days ago!

The most common food intolerances seem to be wheat and dairy. Many people eat wheat and/or dairy several times a day, every single day. So they might not realize if inappropriate energy level, mood, or hunger is coming from the wheat or dairy.

Aside from wheat and dairy, other foods which seem to affect some people are peanuts, corn, soy, nightshade vegetables, shellfish, various grains, and various legumes. Substances in certain foods that might cause problems for some people include histamine, glutamates, GMOs, glyphosate, FODMAPs, salicylates, copper, folates, lectins, and others.

Why Identify Food Intolerances

It's often worthwhile to take simple steps to explore food intolerances because:

  • Food intolerances can have major effects on quality of life and mental health.
  • Modern hybridized plant foods are harsher on the gut, making food intolerances more common.
  • Modern foods are more sterile and less supportive of a healthy gut biome.
  • Toxins such as glyphosate / Roundup herbicide are common in plant foods (especially non-organic grains, legumes, nuts, and canola) and may damage the gut (Samsel 2013).
  • Vegans and vegetarians may eat more of certain plant foods which they tolerate poorly.
  • Vegans and vegetarians may be more susceptible to developing food intolerances. Lectins in grains, legumes, nuts, and seeds can scrape the gut lining. In some people, lectins cause the gut to leak. (Cohen 2018.)
  • It might be easy to make a few changes in diet to avoid trigger foods and feel a lot better.

Food Intolerances: What to Do

1. Identify Food Intolerances

a. Elimination Diets

Try eliminating every trace of suspect foods for a period of time. Then see whether adding the foods back one at a time causes a problem. A good start for everyone might be eliminating wheat and dairy for 6 weeks. Then eat a serving of wheat at every meal for 3 days. See how you feel. If you would like to eat dairy, you could try introducing dairy after that. If the food causes bad effects, stop eating it for some months then try again. If you suspect other foods, eliminate them for 6 weeks too. (See Hyman 2012.)

b. Inundation Diets

It may be difficult for vegans to do elimination diets because there are already limited food options available, even without eliminating more foods. For this reason, I propose an inundation diet. Choose a suspect food (wheat might be a good choice) and try eating a meal with a lot of that food. Monitor how you feel for 3 days: do any health issues get worse?

My first inundation diet experiment involved genetically modified foods, and I decided not to eat them after the experiment. I did a second inundation experiment, involving high-glutamate foods, including peas, tomatoes, and mushrooms, heavily cooked in vegetable stock, plus soy sauce. This meal caused an inflammatory reaction (possibly due to histamine rather than glutamate).

c. Blood Tests

Many people seem to find diet experiments more effective than lab testing. Certain allergy and food intolerance tests are available. Some are newer, run by specialty labs, and/or unlikely to be covered by insurance. Some may be unreliable, and might not show a food intolerance even if it's there. You could talk with your doctor about medical testing for food intolerances.

2. Stop Eating the Most Problematic Foods

The good side of stopping problem foods is you might feel a lot better. The bad side is that you have fewer food choices and also a harder diet for friends, family, and restaurants to accommodate. So I'd suggest stopping those foods that make the most difference, but maybe just cut back on ones that cause minor problems, and continue to eat them in social settings.

I know several people who have found that they feel much better without wheat, but still decided to return to wheat anyway because it's too abundant in the culture and difficult to avoid. Wheat commonly seems to cause mood swings and vastly increased hunger. I don't notice much effect from wheat myself but still don't usually eat it because of modern wheat's reputation for being very genetically different from traditional wheat and for wreaking havoc on many people. I do seem to be intolerant to other foods, such as white potatoes (lead to crashes later), Medjool variety dates (same), brown rice (inflammation), and monosodium glutamate (MSG) (headaches). Once you know more about which foods cause you trouble, you have the options to keep eating, cut back, or cut them out.

3. Takes Steps to Improve Gut Health by Improving General Health

It may be possible to eat some foods and supplements that will heal the gut and thereby heal food intolerances. What's struck me however is how often people doing various nutritional protocols to balance vitamins and minerals end up reporting that food intolerances go away on their own in the process (e.g. CMD 2018; Wilson 2014; Freddd 2012). The food intolerances may be a symptom of other biochemical problems just as much as a cause of them.

4. Prepare Your Grains and Legumes to Minimize Intolerance Problems

Traditional methods include sprouting, soaking overnight before cooking, boiling for an extended time, or, in the case of maize corn, nixtamalizing by boiling with lime (calcium, not the fruit). These methods may make grains and legumes both gentler on the gut and less likely to trigger an adverse reaction.

5. Eat a Variety of Delicious Plant Foods

We still don't know everything about the nutrients and antinutrients in foods. There are many unknown natural substances. Some will turn out to be helpful. Some will turn out to harmful, at least to some people, and require health and body resources to detoxify. If you focus heavily on one food or one group of plant foods (mostly fruits, mostly nuts, mostly grains, etc.), there's a risk. Highly specific diets do seem to work great for some people I know. Many others however prefer a variety of the tasty types of plant foods.