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Question: I am concerned about getting enough protein without milk and meat in my diet. I wonder if you have a list of vegetables and their protein content? Also, what is the amount of protein we need to consume per day? And what about 'complete' proteins or eating complementary protein combinations like beans and rice together, does that matter?

Answer: The most important take home point is that you cannot live off of a balanced plant based diet (whole grains, vegetables, legumes, and fruits) and be deficient in protein...unless you are deficient in calories. The World Health Organization recommends that we eat 5% of our calories from protein... whole grains and green vegetables provide more than that. If you look at the back of a bag of frozen broccoli you will see that in a 100 calories of broccoli you get about 10 grams of protein. I just took a look at a bag of cauliflower in my fridge and it had 2g of protein per serving. A serving size was 20 calories so in 100 calories of cauliflower there are 10g of protein as well. It is true that you would have to eat a large amount of cauliflower by volume to consume 100 calories but that just means you will have to eat for a while. That is precisely what large vegetarian animals like elephants, horses, buffalo, etc. do every day. They get more than enough protein for their huge, muscular bodies just from plants.

Now let's say that you don't feel like eating bags of cauliflower...well, you could eat brown rice all day. In fact, if you look at a bag of brown rice you will see that a serving has 200 calories and 4 grams of protein. So if you required 2500 calories in a day to live/function and ate nothing but brown rice all day to meet those needs, then you would consume 45 grams of protein...which is more than enough. Remember, the World Health Organization says that you need 5% of your calories to come from protein: 5% of 2500 calories is 125 calories or 31 grams of protein...and with brown rice alone, you just consumed 45 grams of protein. So the only way to not consume enough protein in a day is to not get enough calories (when you see pictures of “protein deficient” children in Africa...they are really just calorie deficient) or to get your calories from processed/fake foods where the protein has been removed (Western/American diet) such as twinkies, twizzlers, sugar, oil, etc. So, go ahead and follow a plant based diet, don't starve yourself and don't worry about getting enough protein...that will take care of itself.

As for complete proteins, that idea started over 100 years ago when they researched the protein needs of a rat and applied the results to humans. They found that rats did better on animal proteins but they forgot that rats are not humans! Baby rats double in size every 5 days compared to humans who take about 6 months. Baby rat milk has a much higher protein content than human breast milk to support rats' much higher metabolic needs, for example growing/maintaining hair all over their bodies. Rats have 10 essential amino acids compared to humans who only have 8 essential amino acids. My point is that rats are not humans and their protein needs are much different.

More appropriate for us are the studies done by William Rose in the 1940s regarding protein needs in humans. Rose determined the minimum requirements of essential amino acids in humans. Moreover, he looked at many different foods and found that whole grains/starches provided more than enough of each of the 8 essential amino acids in humans. He thus concluded that a diet (even an entirely plant based one) containing the appropriate caloric need could not be deficient in protein. That is why the idea of combining certain foods to get "complete" proteins is unnecessary and untrue...anyone who researches the data will find this. You can go look up the papers published by William Rose and you will see this data for yourself (see below for links).

So the moral of the story is that you can live off of potatoes and only potatoes and, provided you consumed the correct number of calories (met your hunger needs) you would get more than enough of each of the 8 essential amino acids. Take a look at these Newsletters below from Dr. McDougall's website ( www.drmcdougall.com) as he has many articles on this topic with the references already cited:

http://www.nealhendrickson.com/mcdougall/031200puprotein.htm

http://drmcdougall.com/misc/2007nl/apr/dairy.htm

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