Food allergies and related irritable bowel syndrome (IBS) can be the most devastating things a person can experience in a lifetime. This is especially bad if you don't actually know what you're allergic to. Imagine being afraid to eat, yet still being tremendously hungry. Symptoms of food allergies usually include bloating and diarrhea, which can develop to such a great extent that it pervades into every aspect of your life and has a negative impact on work and social activities, as well as your health.
In my case, I thought I had lead poisoning or something. All my life, I had been able to eat just about anything without any problems. After graduating and moving to another city and buying a condo, all in the space of a year, some pretty nasty things started happening. First of all, I was chronically fatigued. Having just finished a PhD, I didn't find this unusual, attributing it to merely the effects of staying up late to read journals, and ignored it. I then began to develop IBS, but again, chalked it up to stress and figured I could live around it and that it would eventually clear up. I started paying attention when I got chest pains, frequent heart palpitations, blackouts and my hair began to fall out rapidly. That, of all things, finally made me go to the doctor, where I was diagnosed with iron deficiency anemia.
As can be seen on many anemia forums, taking iron supplements doesn't really work, and can worsen IBS. Also, elemental iron can build up in liver-damaging deposits. I wondered why this had happened to me so late in life and so suddenly, when it would have made more sense if it had been a chronic problem, or developed slowly over time.
I was determined to grow my hair back! Not to mention, kick my gut problems so that I would no longer be afraid to eat at a restaurant or go to a conference where I wasn't 100% certain of where the washrooms were. I am now a firm believer in dietary "cures" for problems such as these. Through controlling my diet, and keeping a food journal, I was able to identify which foods were making me worse, and avoid them, giving my gut time to heal. After it did heal, I'm happy to report that I can eat several of the things I had to avoid before, and the anemia is completely gone. In hindsight, here's what I think happened:
1) Incomplete digestion - This happened for two reasons. Stress can trigger the adrenergic responses of the autonomic nervous system, which is the "fight" side of the "fight or flight" response. This suppresses the "vegetative" side of things which includes digestion, specifically secretion of the enzymes needed for digestion. Secondly, because I was constantly in a rush, I would eat in a hurry and not chew properly. Chewing mechanically separates food, increasing the available surface area for digestive enzymes to work, and the motion of chewing sends signals to the pancreas, stomach and liver to begin secreting more enzymes. Prolonged time in the mouth also gives the salivary amylase time to initiate digestion of carbohydrates and starches.
2) Initial gut inflammation - I attribute this one entirely to stress. When there is something wrong with the body, the immune system kicks into high gear so that it can find the problem and repair it. This makes epithelial (skin) barriers leaky, to facilitate the movement of white blood cells through the body's tissues, as they hunt for the problem. The intestine is continuous with the outside skin, and therefore is also protected by a layer of epithelium that separates the body core (blood, bones, etc) from what is inside the gut (food, bacteria, etc).
3) Immune response to food - In order for the immune system to "see" foreign proteins, which they are programmed to destroy, the protein must either carry an archetypal pattern which the white blood cells immediately recognise (usually these proteins are bacterial in origin) or it must be presented to the white blood cells by another cell -- a process called "antigen presentation". A fully digested protein is converted into peptides that are three or four amino acids (the basic units of proteins) in length. Peptides need to be at least 7 to 12 amino acids long to fit in the presentation molecule (MHC molecules) that cells use to "show" foreign proteins to immune cells. If improper digestion is occurring, more larger peptides may be around to be "shown" to leukocytes which will subsequently react to them, leading to more gut inflammation. In an attempt to remove the offending substance, the gut will increase its contractile motions, leading to much unpleasantness and discomfort. The leakiness of the gut just makes the whole problem worse, as normally undigested food should just pass through the bowel with minor discomfort. Since there is increased permeability, there is greater opportunity for contact between the food and the immune cells.
4) Chronic gut inflammation - We have to eat, so the gut is continuously exposed to offending substances. Because the gut is continually trying to purge, absorption of nutrients goes way down, leading to problems like iron deficiency anemia.
5) The fix - Food journaling is where you write down everything you eat and how you felt afterwards. This really helps identify what to avoid. Chewing properly is also essential, and I believe the most important step in solving the problem. No alcohol, since it can strip the epithelium and make it even leakier. No working while eating. Focusing on the food also helps with your body gearing up to digest things properly. Absolutely strict adherence to a hypoallergenic diet for at least 6 months -- this gives your gut time to heal and restore the epithelial barrier, as well give your B-Cells time to settle down into memory cells, which is their less active state. Lots of fibre, which is broken down to butyric acid by bacteria in your gut. Although controversial, butyric acid is believed to force epithelial polarity, which is a state in which the barrier function is intact. Food rotation. Don't eat the same thing every day, since that would increase the probability of your immune system "seeing" it. If the food causes a little bit of inflammation, you might not notice it, but the leakiness has started, which may lead to a bigger problem.
6) The good news - Once the epithelial barrier is reestablished, it's again possible to eat foods that you reacted to previously, since they will pass through the gut without getting into the underlying tissue where the immune cells are lying in wait. If the immune cells don't see the peptides (now properly digested thanks to slower chewing and not reading scientific journals during supper time!) there is no inflammation, no diarrhea, and proper absorption of nutrients, such as iron. Yay! My hair has grown back, my resting heart rate has returned to normal -- abolishing chest pains, and I am no longer afraid to eat at restaurants or go to conferences.
7) Extra info - The trick to growing back hair after a nasty bout of anemia is to get your blood back. Iron is only one component, and if you were short of that, you were probably short of a couple other things, like vitamins B6, B7 (biotin), B12 and folic acid. I know, I know, biotin is in practically everything we eat, but if you're not absorbing it well, it's still a problem. If you have to take iron, Floradix has the least impact on the gut and doesn't taste too bad. However, if you want to avoid iron deposits in vital organs, using a cast iron skillet, eating lots of leafy greens, and combining your iron foods with a mild acid, like orange juice, works pretty good. Also, it's recommended to avoid calcium for two hours before and after eating iron containing foods, since the two elements can compete for absorption. Supplements can help in the initial stages, but like I said, I think dietary sources are best for long term management of the condition.