The gut heals quickly when damage stops and the nutrients we need are readily available. Healing a leaky gut always starts with stopping the damage. Other than an infection of the gut, as a medical doctor and naturopath in my practice I've found that the primary causes of gut damage are NSAIDs (nonsteroidal anti-inflammatory drugs), acetaminophen, excessive alcohol, and consuming foods to which a person is either allergic or intolerant.
Most people don't realize that some foods damage their gut because the effects can happen hours after eating. Of course, immediately getting hives from eating a food makes such allergies obvious. But the ones that don't immediately cause symptoms are very hard to recognize. And to make matters more complicated, problem foods are unique to each individual. However, after seeing hundreds of patients with leaky gut, by far the worst foods I have seen are, in decreasing order, wheat (including rye and barley), dairy, peanuts, soy, corn, and tomatoes.
The best foods for the gut are those rich in nutrients that promote healing and foods that either inhibit toxic bacteria in the gut or promote the growth of bacteria that are good for the gut.
1. Foods rich in glutamine.
What does it do? A key nutrient to promote gut healing is the nonessential amino acid glutamine. While this important nutrient is available in many foods, it is very heat sensitive and breaks down easily when food is cooked. So, while meat is rich in glutamine, few people eat raw meat.
Where can I find it? Raw milk has good level of glutamine, but pasteurization greatly decreases the levels. I've seen the best clinical results with eating cabbage family foods, such as cabbage (red and purple are best), broccoli, Brussels sprouts, etc. However, they must be eaten raw and as soon as possible after cutting or juicing. This family of goods is also great for promoting liver detoxification enzymes.
However, I don't recommend eating more than the equivalent of ½ head of cabbage a day as it can bind to iodine and too many people are deficient in iodine.
2. Foods rich in quercetin.
What does it do? The bioflavonoid quercetin is very helpful for protecting and healing the gut as it decreases inflammation that is the primary way the cells of the intestinal lining are damaged.
Where can I find it? The foods rich in quercetin with the highest bioavailability in humans are onions (yellow or purple, not white) and apples. Interestingly, my friend Michael Ash, ND, DO, from London, lectures that stewed apples are the healthiest food he knows for the gut.
3. Fermented foods.
What does it do? A large amount of research shows that naturally fermented foods are excellent for gut health.
Where can I find it? Perhaps the best are sauerkraut and kimchi. These foods not only provide healthy lactobacilli bacteria, but they are also rich in glutamine. Naturally cultured dairy products are great at providing healthy bacteria, but be sure you are not allergic to them.
4. Traditional spices.
What does it do? Several traditionally used spices have been shown to improve gut function and decrease gut permeability.
Where can I find it? The one with the best is turmeric, which is rich in curcumin. This yellow root has been used in curries for millennia. Like quercetin, it decreases inflammation in the gut, the primary cause of excess gut permeability. This decrease in inflammation occurs not just in the gut but throughout the body. This may explain its remarkable anti-cancer benefit, which has been documented in over a hundred research studies.
If you think you might have a leaky gut, check out my book The Toxin Solution. It goes in-depth into the lifestyle changes you can make for optimal gut health.