Tuesday, January 15, 2013

Book Review: The Vegetarian Diet for Kidney Disease

"Ecologically Grown Vegetables"
Photo by Elina Mark
(Courtesy of Wikimedia)
As I've written on this blog before, my wife Caryl (pronounced "Carol") and I are vegetarians.  She is also a diabetic, plus she has high blood pressure, and needs to watch her sodium and cholesterol.  Caryl had gotten her diabetes under control when the "other shoe" fell -- she now has first stage kidney disease.

The doctor recommended a low potassium diet and gave her a list of no-no foods -- all of which were things we vegetarians rely on: beans, potatoes, lentils, soy, oranges, avocados, tomatoes, squash, nuts, and a ton of other veggies.  Just imagine trying to be a vegetarian without using these basic foods.

A search online revealed kidney disease diets that were all heavily meat-oriented for protein sources -- not an option for us, both because of our commitment to vegetarianism and the fact that we keep kosher and live in a rural area where kosher meat is not easily available.  This was so disheartening to Caryl that she plunged into depression. What on earth COULD she eat?  Food just did not seem interesting or palatable anymore.

Then I found this book by registered dietitian Joan B. Hogan, who specializes in renal nutrition.  Not only does it deal with vegetarianism and kidney disease, it talks about combinations of diseases -- such as having both diabetes and kidney disease.  As Hogan explains, it used to be believed that vegetarianism and kidney health did not mix, and that animal proteins were superior to proteins obtained from plants, based on early studies of baby rats.  But this is now changing.  As Hogan says, "This theory is now history, for we are not rats."

 Hogan's approach to menu planning is much more sensible than the old flesh-centered renal diet.  Rather than outrightly forbidding various foods, she classifies them as high, medium, and low potassium.  Sort of a "Chinese menu" approach where you can choose one from list A, two from list B, and three from list C per day. So, for example, Caryl can have an orange (high) if she doesn't have a tomato (high) the same day. Or she could have half an orange at breakfast and a slice of tomato later in a sandwich. This allows for a whole lot more flexibility and variety in the menu. (The same goes for other nutrients, but since potassium is what brought us to this book, this review focuses primarily on that.)

And there are lots of charts for various foods to compare levels of protein, potassium, phosphorus, sodium, etc., as well as a useful chart on commercial meat substitutes. (Which is why you should buy the book version, NOT the kindle version, which renders the charts totally unreadable. Besides, having the book on the shelf right there next to your recipe books is more convenient.)

There is also a very useful list comparing various types of beans, where I learned that pinto beans have half the potassium of white beans -- so by changing the beans we use in a favorite soup, we could cut the potassium way down and still enjoy it in smaller portions.

One thing that the book does not have is more info on how cooking and other preparations affect various foods. There are recipes with stats for the complete recipe, but not for individual cooked ingredients. For example, she mentions "soaked potatoes" in a chart but does not say how long to soak them, or how soaking affects their potassium level. I assume she means soak them raw and pour off the water?

I do know that potassium is water-soluble, so when we cook potatoes (and a lot of other veggies) we no longer use the water they were cooked in for soups.  Ditto for beans, which we first soak overnight, then pour off that water and use fresh water for cooking.  I assume this lowers the potassium levels of the foods, but some statistical comparisons between raw and cooked vegetables would be very helpful. And how does sprouting lentils and mung beans (both high potassium but also soaked first and rinsed repeatedly as they grow) change their statistics?

I later discovered that a lot of this type of info can be found on the USDA Food Composition Database, where, for example, a search for "lentils" did find comparisons between raw, cooked, and sprouted.  This info, plus Hogan's book that pointed us in the right direction for figuring out how to balance a renal vegetarian diet, has made life a lot more bearable.  Caryl is no longer so depressed and we are now enjoying food again.  Plus her potassium was normal last blood test. I give it ten stars!