Inflammation From Plant Foods 101


This is a brief review of substances in plants that some people might be sensitive to. It does not mean that everyone is sensitive to all of these things, and what we are sensitive to depends on genetics, infections, gut microbes, lifestyle, stress, toxins, etc. Most of the foods discussed here can actually be quite healthy for you, so if you don’t react to them and they don’t harm you, then there’s no real reason to avoid them.



Inflammation coming from lectins is becoming more prevalent.  Lectins are resistant to cooking and digestion, and may be inflammatory for many people. Because they are so resistant to digestion, lectins can make it pass the gut barrier and bind to organs inside the body.

Lectins bind to carbohydrates, which is why carbohydrates themselves can “block” lectins. N-acetyl glucosamine is one such sugar that can block wheat lectin.

Lectins can also stimulate class II HLA antigens on cells of organs that normally wouldn’t present them, including pancreatic and thyroid cells. (R)

Autoimmune diseases are characterized by the expression of human leukocyte antigens (HLA). (R)

Rheumatoid arthritis is characterized by IgG molecules deficient in galactose.  A normal IgG molecule will have galactose on the end, but in rheumatoid arthritis, the galactose is missing. This means the molecule on the end is N-acetyl glucosamine, which wheat lectin has a high affinity for, and is probably why wheat is a common trigger of symptoms in persons with rheumatoid arthritis. This is also why supplemental N-acetyl glucosamine may help reduce symptoms of rheumatoid arthritis.

Lectins can also damage and remove the mucous coating that protects the gut wall, and can cause mast cells to release histamine in the stomach. (R)

It’s likely that lectins cause mast cells to release all kinds of inflammatory mediators in the entire gut.

Lectins can damage the cells of the gut, decrease digestion and absorption of nutrients, change the balance of gut bacteria and influence the immune system. They can also increase or decrease the size of internal organs, as well as alter hormones. (R)

We should all know by now that wheat is usually bad for you if you have chronic inflammation, has the ability to increase intestinal permeability, which is associated with a lot of health disorders, including but not limited to inflammatory bowel disease, asthma, chronic fatigue syndrome, and depression. (R)

From my own experience, not only wheat itself, but also most whole grain products destroy my gut. White rice, brown rice crispy cereal, brown rice pasta and flour products I tolerate very well, but anything else is terrible for me.


Foods high in lectins (not a complete list):

  • Whole grains
  • Legumes
  • Nuts
  • Seeds
  • Nightshades (peppers, potatoes, tomatoes)


To reduce the lectin content of foods, cook thoroughly.  To lower the content even more, pressure cook higher lectin foods. Or better yet, try an elimination diet of avoiding high lectin foods.


Biogenic Amines


Biogenic amines, also termed vasoactive amines, are produced through bacterial fermentation. Histamine is a biogenic amine, and is the most frequently associated with food intolerances and reactions.  Excess histamine in the body can lead to increased stomach acid and heart rate, flushing, headache, itching and hives, and bronchospasm. (R)

Histamine intolerance and mast cell activation disorder are associated with elevated levels of histamine, and persons with either disorders often have a difficult time tolerating foods high in histamine. Some foods may cause mast cells to release histamine, but there isn’t enough evidence supporting this claim.

Headaches are pretty common for people who are sensitive to biogenic amines. A diet low in biogenic amines was found to reduce chronic headaches, as well as reduce hives and itching. (R)

For more information about histamine intolerance and mast cell activation disorder, click here.

Other biogenic amines besides histamine:

  • Betaphenylethylamine
  • Tyramine
  • Tryptamine
  • Putrescine
  • Cadaverine
  • Spermine


Plant Foods high in vaso-active amines (not a complete list): (R)

  • Citrus: Oranges, tangerines, lemon, lime
  • Bananas
  • Pineapple
  • Grapes
  • Strawberries
  • Papaya
  • Tomatoes
  • Avocados
  • Eggplant
  • Pickled, cured, aged, smoked, and fermented foods
  • Spinach
  • Peanuts
  • Nuts and seeds
  • Tea
  • Coffee
  • Chocolate
  • Wine, beer, champagne



FODMAPs (Fermentable Oligosaccharide, Disaccharide, Monosaccharide, And Polyols) are carbohydrates and polyols that are highly fermentable by gut microbes. They are hard to digest and poorly absorbed, which means they make their way down to where the microbes in our gut live. Here in the lower intestinal tract, microbes feast of these FODMAPs. The fermentation can cause lots of gut issues in those who are susceptible, such as increased bloating, distention, gas, cramping, diarrhea, and other unwanted symptoms. A low FODMAP diet is quite popular, which helps alleviate a lot of these irritable bowel syndrome (IBS) symptoms. A low FODMAP diet can also help persons with inflammatory bowel disease (IBD). (R)


High FODMAP Foods (not a complete list):

  • Wheat
  • Legumes
  • Onions
  • Garlic
  • Broccoli
  • Asparagus
  • Avocado
  • Fructose
  • Apples
  • Cow’s Milk (lactose)


For more information about FODMAPs, read this article.




Oxalates decrease the absorption of minerals, such as calcium and iron. Although oxalate is poorly absorbed, once it is, it can bind to calcium and form kidney stones. (R)

Since 75% of kidney stones are made of calcium oxalate, it seems reasonable to lower oxalate intake if one is susceptible kidney stones. (R)

To reduce the amount of oxalate, boiling is better than steaming, and steaming is better than baking. (R)

High oxalate foods (not a complete list):

  • Grains
  • Legumes
  • Nuts
  • Seeds
  • Spinach
  • Beets
  • Swiss chard
  • Grapes
  • Berries
  • Kiwi
  • Cocoa
  • Tea




Nightshades contain solanine, which is an alkaloid believed to cause inflammation. The research is lacking, but you can’t deny that many people with chronic inflammation, such as arthritis, find relief when they remove nightshades from their diet, especially when eliminated with other potentially inflammatory foods. (R)


Nightshades include (not a complete list):

  • White potatoes
  • Tomatoes
  • Eggplant
  • Bell peppers and hot peppers


Phytic Acid (Phytate)

Although I’m discussing the drawbacks of phytic acid, you should know that phytic acid has anti-cancer, antioxidant, and blood sugar lowering benefits.

Phytic acid is known as an anti-nutrient, meaning that it binds to and blocks the absorption of minerals like iron and zinc. (R)

Phytic acid can also inhibit digestive enzymes, and coupled with decreasing the absorption of minerals, consuming a diet high in phytic acid could potentially lead to mineral deficiencies.

People who should decrease phytic acid intake are those who are susceptible to mineral deficiencies, which include people who are either already deficient in minerals and need to increase levels in the body, or people with gut issues who have a difficult time absorbing minerals. Supplementing with minerals may be a way to offset phytic acid intake as well.


Foods high in phytic acid (not a complete list):

  • Whole grains
  • Corn
  • Legumes
  • Nuts
  • Seeds


Ways to decrease phytic acid:

  • Eat refined grains, the bran is removed, which unfortunately also removes nutrients
  • Soak and rinse
  • Ferment
  • Sprout
  • Consume high vitamin C foods with high phytic acid foods



Although fiber is generally a good thing, too much fiber at the wrong time can be a bad thing. If you are having severe gut inflammation, then you may find relief by reducing the consumption of certain fibrous foods like whole grains, corn, nuts, seeds, beans, and raw fruits and vegetables; with the exception of apple sauce, melons, and bananas.  Fiber is rough and course, which can aggravate symptoms. (R)

Eating cereal grains during bouts of gut inflammation is like scratching an open wound, especially if you are having an inflammatory bowel disease flare.

Fiber is essentially a prebiotic, meaning it feeds gut microbes. A diet rich in fiber is great for increasing levels of good bacteria and maintaining a healthy gut microbiome. However, in the case of bacterial overgrowths, a fiber diet may not be the best thing for everyone.




An intolerance to salicylate leads to an increased production of inflammatory mediators. (R) Reacting to aspirin is a tell-tale sign of salicylate intolerance, but there are also many foods that can contain high amounts of salicylates as well. (R)

Symptoms of salicylate intolerance include: (R) (R)

  • Plugged or runny nose, sinusitis
  • Asthma
  • Gas
  • Diarrhea
  • Colitis


High salicylate foods (not a complete list):

  • Most spices and herbs
  • Curry
  • Peppers
  • Oregano
  • Mustard
  • Cayenne pepper
  • Raisins
  • Pepper
  • Oranges
  • Apples
  • Pears
  • Potatoes
  • Sweet potato
  • Apricot
  • Pineapple
  • Almonds
  • Raspberries
  • Dates
  • Coffee
  • Most nuts and seeds
  • Berries
  • Coconut oil
  • Olive oil
  • Dried fruits




Sulphites are added to foods to reduce oxidation, prevent browning, and control bacterial growth.

Sulphites are most likely to bother people with asthma. (R)

Symptoms of sulphite sensitivity: (R)

  • Wheezing
  • Bronchoconstriction
  • Nausea
  • Stomach cramps
  • Diarrhea
  • Itching
  • Hives
  • Throat swelling
  • Flushing
  • Hypotension.


Foods moderate or high in sulphites (not a complete list): (R)

  • Wine
  • Molasses
  • Sauerkraut
  • Lemon juice
  • Dried Fruit
  • Vegetarian meat products
  • Cider
  • Dried potatoes
  • Grape Juice
  • Wine Vinegar
  • Gravies and sauces
  • Fruit topping



*Be sure to work with a qualified health care professional if you decide to do an elimination diet, especially if you are testing multiple sensitivities.