Ask The Trainer #68 – Blood Type & Diet


I wanted to ask about soy products and dietary restrictions. I uphold the Blood Type Diet and being an A type, I am not supposed to eat red meats or use whey and casein products. However, as a weightlifter and conscious dieter with consideration for macronutrient intake, protein can sometimes be difficult depending on my day. Generally, I try to take in about 30% of my calories from protein or about 1 gm/lb of LBM. So sometimes I supplement with soy protein. I’ve read that as long as I take in enough microgreens that it can help with the negative effects of soy products. I just wanted to get your thoughts on two things: 1) the blood type diet and 2) intake of soy products due to restricted diets.

Thank You,



Hi, Shawn,

I’ve heard of blood type specific diets. Based on available evidence, I find myself agnostic about these diets. The main premise of blood type specific diets has to do with proteins called lectins, which have the ability to bind to sugar molecules. Scientists believe these substances to be anti-nutrients and could have negative effects on the lining of the stomach.

According to the blood type diet philosophy, there are numerous lectins in the diet that specifically target different A, B, and O blood types. It suggests that eating the wrong types of lectins may result in agglutination, or red blood cells clumping together.

Raw Legumes

There is some evidence that a very small percentage of lectins in raw, uncooked legumes can trigger agglutinating activity specific to certain blood types. For example, raw lima beans may interact only with the red blood cells in people with blood type A.

However, research has shown that the majority of agglutinating lectins react with all A, B, and O blood types, In other words, lectins in the diet are NOT blood-type specific, with the exception of a few varieties of raw legumes.

At the end of the day, this probably isn’t all that significant considering most legumes are soaked or cooked before they are consumed, which would destroy any harmful lectins.

Chad Shaw

I personally feel the human body thrives on a variety of protein sources. That being said, I can also appreciate an individual’s ethical decision to avoid animal-based proteins based on their personal beliefs. In fact, I have a number of friends who’ve become vegans because of their passion for animal welfare. There’s nothing wrong with that.

Heck, if, for some bizarre reason, I was forced to take care of a baby cow for a day, I can almost guaranty that by the end of that day, I’d be ready to give up beef for the rest of my life!

Soy Protein

Now, I’m going to level with you on the issue of soy. I personally hate soy. Not because of how it tastes, but because the problematic chemicals it contains. To begin with, soy contains potent enzyme inhibitors that block the action of trypsin and other enzymes protein requires for digestion.

These inhibitors are large, tightly structured proteins that are not completely deactivated during the process of cooking. They can produce significant gastric distress, reduced protein digestion, and set the foundation for deficiencies in amino acid uptake.

In animal studies, diets high in trypsin inhibitors cause enlargement and pathological conditions of the pancreas, including cancer. It is worth mentioning that when soy ferments, these enzyme inhibitors deactivate. So if you need to eat soy, eat fermented soy only!

Moreover, soy contains goitrogens or compounds that block the synthesis of thyroid hormones and disrupts iodine metabolism. In turn, this disrupts normal thyroid function and possibly causes hypothyroidism in some cases. People who’ve been diagnosed with hypothyroidism will attest this is a miserable road to travel.

Soy And Estrogen

Additionally, soy contains chemicals known as isoflavones. The 3 most notorious isoflavones are genistein, daidzein, and glycitein, which act as phytoestrogens, or plant estrogens in the human body. They are structurally similar to the female hormone estrogen. Researchers believe it has similar effects in the body when they bind to the estrogen receptors of our cells.

Since high estrogen levels in men are associated with low testosterone levels, eating soy is frequently blamed for low testosterone levels. If you really want to adhere to a plant-based, or vegan diet, I’d suggest trying to obtain more dietary protein in the form of hemp, peas, quinoa, nuts, lentils, and beans.

Hopefully, this answers both of your questions. I wish you all the best in your training and health!

Prove ‘Em Wrong,
Chad Shaw

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