Discussion Board

Hey Jeff,

I'm in AP Biology, and we're on the chapter about Animal Nutrition. The book (Campbell-Reece, 8th edition) was written in 2008.

The first thing it talks about is essential amino acids, claiming that humans have 8, and that animal protein has all 8 and are "complete" proteins, while plant proteins are always deficient in at least one and are thus "incomplete."

I've heard many doctors say that this is false science. Why would my biology textbook claim this is true?

Thoughts?

Thanks,

Brandon

http://www.drmcdougall.com/misc/2007nl/apr/protein.htm

In Health
Jeff

I've seen that link, which is where the confusion arises.

So you're telling me that my biology textbook is wrong? What a shocker...

http://www.diseaseproof.com/archives/di ... -away.html

In Health
Jeff

PS just punch any plant food into the official USDA Database & you will see they contain all the essential amino acids.

Exactly what I was looking for. How do you find the perfect links everytime?!

Thanks Jeff, now I can argue with my teacher

I am having difficulty understanding Rose's charts. The charts say grams of protein for various foods but he does not say the quantity of food. So many grams per calorie, per 100 calories, per weight? And what do the totals at the bottom mean. They are not the sums of the individual numbers. Could someone please explain this?

None of this gives information on the requirement for individual essential amino acids. For instance, if you were eating brown rice as your staple food, if it were very low in one essential amino acid, how much would you have to eat per day to meet the requirements for that particular essential acid?

Didi

The charts are McDougalls charts and not Roses charts and are based on 3000 calories of each food.

However, the WHO and the NAS have set recommended Amino Acid intakes which, along with total protein, are easily met even by the consumption of one food (except for fruit) at a reasonable caloric intake.

Protein complimenting is just not accurate whether referring to amino acid content (having all of them) or amino acid amount (enough of all of them) & I will post a detailed response later explaining this.

The bottom line, as i said in the linked article is the textbooks are wrong.


In Health
Jeff

Terminology I've seen in the "incomplete protein" line is that the proteins are not incomplete, but that there is a "limiting amino acid"--one in such a small quantity that it makes the food "low-quality protein." E.g.: "A complete protein contains all the indispensable amino acids in the approximate amounts needed by humans. . . . Incomplete proteins or low-quality proteins are derived from plant foods. . . . Most plant foods tend to have too little of one or more particular indispensable amino acids. The term limiting amino acid is used to describe the indispensable amino acid that is present in the lowest quantity in food. Listed in Table 6.13 are examples of incomplete protein containing foods and their limiting amino acid(s)." Advanced nutrition and human metabolism, Sareen S. Gropper, Jack L. Smith, James L. Groff, Wadsworth Cengage Learning 2005, 2009.

But wouldn't all foods have one "limiting amino acid," by this reasoning? And they can't mean "in the approximate amounts," can they? Wouldn't they have to say "in the approximate ratio" to make sense? You won't get the approximate amount of amino acids needed by humans from beef if you eat an ounce of it.

As I mentioned above, the limiting amino acid theory is also completely inaccurate.

I will explain later when get back from traveling

In Health
Jeff

Happy Trails to you!

-dog