Many thanks, Heidi, for taking the time to answer our questions in such detail. I am a 47 year old male Type-A secretor with one of those "hair-splitting" food questions (we "A-types" are famous for our attention to detail) that nevertheless has been nagging me for some time. Peanut oil is listed as a Type-A AVOID "artherogenic" (artery clogging) fat, while Peanut Butter, which seems to contain significant amounts of this oil, is listed as Type-A BENEFICIAL. I love natural, unsalted, additive-free peanut butter and I enjoy it daily, but I'm wondering if I'm setting myself up, over the long run, for a Type-A susceptibility to cardiovascular problems. Do you have any words of wisdom that might persuade for-or-against eating peanut butter because of its oil content? Would the regular use of extra virgin olive oil help moderate the harmful effects of fatty peanut butter? Blessings... Mark

Hello, Mark! ;-)



The food list item "peanut oil" does not refer to the naturally-occurring oil in peanuts (and peanut butter). It refers to the manufactured product, usually extracted using high heat or chemical processes -- then stored on shelves without refrigeration until (and after) purchase. The primary home and restaurant use of this oil is in high-heat frying.



While commercial establishments are required by law to repeatedly test their oil to ensure it is "safe," TV alone provides plenty of chefs who use this oil and others in extremely hot pans and fryers, billowing smoke. The polycyclic aromatic hydrocarbons ("PAHs") formed in this process have been implicated in several forms of cancer (especially stomach cancer). So, from my reasoning, if everyone chose an organic peanut oil and used it in small amounts to flavor dishes, I'd be happy. Luckily, the blood type diets are smarter than I am.



Os and Bs avoid both peanuts and peanut oil because of the peanut lectin. Secretor ABs derive more benefit from the lectin in peanuts than the nonsecretors do, but the oil drops to neutral for both of them, rather than avoid for either, since their ability to handle fats is somewhat enhanced by their B genetic heritage.



For As, it is a secretor avoid and a nonsecretor neutral -- because the A nonsecretors have a slight advantage in breaking down the oil components in this case. I know the comparative intestinal alkaline phosphatase issue among the blood types has not yet been confirmed in thorough detail, and I can't help there. But the relative avoid status of peanut oil between secretor and nonsecretor As appears to lie in the effect of its triglyceride structure upon cholesterol levels and arterial plaque formation in type A, with nonsecretors being less vulnerable to this effect than secretors are.



I hope this provides more food for thought! and thank you for writing!!