I've added a few vegetables and roots to the Phytic Acid wikipedia article, not because I worry about phytic acid, but because I share Alexandra's opinion and I wanted to refute the idea that only grains and seeds contain phytic acid. If you would like to request data for a plant, just ask in the comments. Not too many please though since I don't have that much free time lately.
OK, yeah editing wikipedia takes forever because it's such a pain to format, but here's a useful chart from this book
I think the fear of oxalates and phytates is overblown. If one is predisposed to certain kind of kidney stone, a low oxalate diet may help -- I say may -- because it is not successful for everyone. Some women find relief from vulvar pain and/or cystitis by eating a low oxalate diet but this strategy does not work for everyone. There appears to be a wide variety of sensitivity to oxalates. Also, certain spices such as turmeric can impact the excretion of oxalates in the urine. Even with an oxalate sensitivity, one could alleviate some problems by eating the high oxalate food with a bit of dairy -- perhaps this why some traditional dishes with the very high oxalate veggie, spinach, is often paired with cheese. Alternatively, one could dilute the oxalate effect by drinking extra water -- I spoke with a nephrologist friend who himself is prone to kidney stones (familial) and he loves the high oxalate foods -- especially chocolate, almonds, and spinach -- his motto is dilute, dilute dilute and of course modify portions. Supplementing with magnesium citrate or oxide may help as well. As for the phytate issue -- I go back and forth on this as I love raw nuts -- very high in phytates. With all the dire warnings about how they block minerals, I've decided to put this in the same category as oxalates -- individual sensitivities and make-up of the rest of one's diet would dictate amount of consumption. As a lover of huge amounts of raw nuts -- I have no evidence of mineral deficiency and I do not eat dairy any more. I haven't had Dr. Kruse's recommended mag test yet but all previous ionized mag and calcium tests have been ideal. I have painfree menstrual periods and never get headaches or body aches etc that could indicate mineral deficiency. I am nearly half a century old and do not have a single cavity. Raw nuts digest easily for me. So do dry roasted. Huge amounts -- no stomach distress whatsoever. There is also evidence that phytates may have health benefits. I think the danger of isolating elements in foods like phytates and oxalates while ignoring the rest of the health and pleasure benefits of the food could lead one down the same path as pathological fear of omega-6 or fructose which leads people to shun walnuts and pears. If you love certain foods that are high in oxalates and phytates and are concerned -- simply cut back on portions and frequency.
Most lists on the internet (or even given in doctors offices) that list the oxalate content of foods are wrong. They do not reflect new, more reliable testing methods or they don't reflect true, reasonable portion sizes (e.g. black pepper is often considered high oxalate because 100 grams of it is high oxalate. But most people only eat about half a gram or less at a meal which is a low oxalate serving.)
The two most reliable and comprehensive lists are available in the Low Oxalate Cookbook Book 2 published by the Vulvar Pain Foundation http://thevpfoundation.org/vpfcookbook.htm
and in the file section of the yahoo.group, Trying Low Oxalates http://health.groups.yahoo.com/group/Trying_Low_Oxalates/
A reliable, but not comprehensive list can also be found at http://www.lowoxalate.info/recipes.html
Not a list, per se, but a pretty in-depth discussion of the plant kingdom's chemical arsenal here: http://www.westonaprice.org/food-features/plants-bite-back
And one of my favorite book passages, from Susan Allport's The Primal Feast, here: http://tinyurl.com/6cdzwjm
Regarding the nuts -- I forgot to mention that another previous concern of mine from reading articles by the "nuts are anti-nutrients and must be specially soaked prepared" crowd was that the phytates could cause calcium deposits in arteries or other unwanted places. But then I read that Dr. Davis (Heartscan blog) eats unlimited amounts of raw almonds and scans himself -- no problems. Every food has pluses and minuses. Heat treating the nuts damages/alters the fats. The fiber in the nuts makes a significant part of the caloric content unavailable. Dr. Davis had a nice piece on this on his blog. But if nuts cause reactions -- ditch em. My husband gets swollen throat with any raw nut-- worst is walnuts for him -- but dry roasted he can tolerate almonds. My problem is I love them and can eat copious amounts. Here's where I agree with the food reward theory -- especially the whole experience of cracking fresh hazelnuts -- delicious and fun.
Obviously if one has a known problem with oxalates than avoidance is always an option. The advice I gave was not "mine," it came from a kidney specialist friend who himself is a stone former (different stones require different diet/supplements and nothing works 100% for everyone). He loves nuts and chocolate and has found that diluting with lots of water and eating a bit of cheese with his nuts and chocolate prevent stone formation in him. He did not say that he can eat huge amounts of problem foods -- I specifically mention modyfiying portions. If one can live entirely without oxalate foods -- fine-- but not everyone is willing or even needs to do this. For many, the devil is in the dose.
Becoming dehydrated while also eating many high oxalate foods (many of the highest such as spinach, okra, dandelion greens, eggplant) are summer foods and even a person with no previous oxalate issues could develop an issue if that person does not stay well hydrated especially when following a low carb diet as such a diet has a natural diuretic effect. Thus the urine could become too concentrated. Unsuspected confounding causes such as using therapeutic doses of cinnamon and turmeric can also greatly increase oxalate secretion in the urine and cause discomfort if not stones in some people. Operative word "some." Some simply do not feel discomfort of form stones no matter how many oxalates they ingest or excrete in their urine. I had a problem 2 summers when I was not careful to hydrate sufficiently. Stones are much more common in the summer months and in tropical or hot regions precisely because it's harder to maintain water volume in the body.
But if you can live life happily avoiding oxalates -- then go for it. I just do not believe that is necessary for everyone -- it wasn't for me. Your mileage may vary. Ditto for gals with pelvic pain -- some find relief cutting oxalates and others find no such benefit.
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