Diet taboos for people with type AB blood

The blood type diet theory has not been generally recognized by the global clinical nutrition community. All dietary rules cannot replace individual body feedback, let alone the dietary requirements of underlying diseases.

Among the 20 or 30 friends with AB blood type that I have come into contact with, the biggest pitfall is red meat. Two years ago, there was a girl who worked as an Internet operator. In order to reduce body fat, she followed the blogger to eat a "high-protein fat-reducing meal". She ate 200g of fried steak every day at noon. Within three weeks of eating, not only did she not lose weight, but she felt sleepy every afternoon, suffered from acid reflux and bloating. When she checked, she found that her LDL was much higher. Later I learned that people with AB blood type generally have low gastric acid secretion. The high-density animal protein and saturated fat in red meat require sufficient gastric acid to be completely decomposed. Eating too much will not only have low digestion efficiency, but also excess nutrients will easily accumulate in the body, which will put a burden on the body. The adjustment suggestion I gave her was to reduce the amount of red meat to no more than 2 times a week, no more than 100g each time, and pair it with high dietary fiber side dishes such as vinegar-soaked kelp or broccoli. Within a month, her flatulence problem was basically eliminated, and her body fat gradually dropped.

In addition to red meat, the seafood selection also needs to be a little more sophisticated. It’s not that you can’t touch all seafood, but people with AB blood type are more likely to be allergic to stale tuna, salmon, raw shellfish, and crayfish, which contain high histamine content, than other blood types. After all, type AB is a fusion blood type of type A and type B. The structure of immunoglobulin is relatively special, making it easier to react to foreign heterogeneous proteins. Not long ago, a friend with Type AB ate unrefrigerated sashimi and went to the emergency room with hives all over his body in the middle of the night. The doctor said that he has a constitution with high immune sensitivity. In this case, he can actually avoid stale high-histamine seafood. If he doesn’t react at all to fresh shrimps and fish, there is no need to specifically avoid these foods.

There is another detail that many people have not noticed: Strongly stimulating diets often have a greater gastrointestinal impact on blood type AB. Foods such as strong coffee, high-alcohol liquor, and spicy hot pot can easily disrupt the inherently unstable rhythm of digestive enzyme secretion in Type AB. Eating it once in a while may be fine, but eating it continuously can easily cause gastrointestinal disorders. I used to have an AB-type colleague who relied on three glasses of iced Americano every day while working on a project. After a week of continuous stomach cramps, he went to the hospital. Later, he figured out a routine on his own. If he needed to drink coffee, he would choose a warm latte with half a cup of milk, and basically he would not suffer from stomach discomfort.

But having said that, the blood type diet theory itself is really controversial. I have checked a lot of academic information before, and many clinical nutritionists believe that there are currently not enough large-sample randomized controlled trials that can prove the direct relationship between blood type and dietary suitability. Last year, there was a foreign study that tracked 1,500 volunteers with different blood types and gave them the same low-oil and low-salt diet. The final weight loss and blood lipid improvement effects had no obvious correlation with the blood type. To put it bluntly, the dietary taboos we are talking about now are more like common experiences summarized based on a large number of individual feedbacks, not iron rules that must be followed.

When it comes to dietary advice for type AB friends, I don’t think it’s necessary to memorize any taboo lists. If you don’t feel uncomfortable after eating red meat, but you are usually a little iron-deficient and anemic, it’s absolutely fine to eat more. ； If someone who eats spicy food and drinks ice has never had a stomachache, there is no need to force yourself to quit this or that. If you are really unsure, you can keep a food diary. If you feel uncomfortable after eating something, just avoid it next time. This is more reliable than any general taboo list. After all, when it comes to eating, your physical feelings are always more important than any theory, right?