Response to blood type--kinda long:
Actually the blood type thing is VERY scientific, regarding food lectins and how they react to certain blood types. They test food lectins by putting some blood under a microscope then adding the food lectin to it. You can actually watch the blood cells change form or explode when they come in contact with the offending lectin. (That's also basically how an allergist tests for allergins that don't show up on the skin prick test. I was tested for penicillin on a skin prick and it showed negative. I told the allergist I was *highly* allergice to penicillin, so he drew blood and introduced the penicillin--my blood cells disintegrated on contact with the penicillin)
For example, cows milk is very B-type like in certain aspects--a blood Type A or O who drink milk would react to it whereas a B-Type wouldn't. Our body's immune system is on the constant lookout for anything it perceives as not 'family'. So if an O or A drinks milk which puts a B-like substance in the body, the immune system will kick in and try to kill the invader. It can result in a host of symptoms, some of which we can easily ignore, some we can't. I'm an A and I know that when I gave up milk entirely my sinus trouble and allergies went away and my acid reflux went away. I also gave up nightshade veggies. My B-type friend gave up chicken, tomatoes and corn. Within a month she was frankly amazed at how much better she felt--she was even getting comments from co-workers about how good she looked, even though she hadn't told them anything about changing her diet. Also someone she knows who claims to be able to read peoples 'auras' said she noticed Sharon's aura had changed and what had she (Sharon) done in her life recently? Sharon then told her she'd made some changes in her diet.
Now having said that, I go along with the lectin thing regarding blood type, but I don't go along with saying A-types should avoid meat because they are supposed to have a tendency to produce a more alkaline stomach acid which won't allow them to properly digest animal proteins (but is supposed to be very beneficial for digesting vegetable protein). Also A's are supposed to have less alkaline phosphatase in their intestines which supposedly also prevents proper assimilation of animal proteins and cause the whole mess to just ferment. (Apparently B's and O's are not subject to this problem, as red meats are actually highly recommended for O's and is an OK for B's). I appear to be an A who not only can tolerate red meat, but actually does well on it. I followed the A-type diet for 14 months and felt miserable (yes, I did the soy, tofu, beans for protein thing). I became diabetic eating that way and I had gotten to a point where I would have eaten a cow alive. I had my kineseologist test me on various aspects of the blood type diet and we found that on every 'No No' given regarding lectins my muscle testing failed, but on the red meat I came up strong (except on pork--I failed that over and over again). So I do a combination of Bernstein/Atkins tempered by my blood type lectin avoids. I also have gotten into the pH thing (eating more alkaline) and I'm pleased with my results. It's taken a lot of 'tweaking', but I'm very glad I did.
Since B's do so poorly with chicken, then anyone doing the low carb thing who are eating a great deal of chicken who also just happen to be a B-type, they may not feel so great. Just a suggestion to any B-types out there: *Try* giving up chicken, tomatoes and corn and see if that helps.
Any blood type questions regarding applying the basic principles of it to doing low-carb, feel free to ask. I can make recommendations based upon my own observations. I know for sure I am an exception to the no-meat-eating A-types, but that doesn't mean the basic concept of blood type and the affects of food regarding blood type is flawed. It just needs further research, but is worth a try if things aren't going quite right for you. Then there's also candida infestation, but that's a whole 'nother thread....