08-16-2012, 01:04 PM
(This post was last modified: 08-16-2012, 08:38 PM by Tenet Nosce.)
(08-14-2012, 03:39 PM)Bring4th_Monica Wrote: Great post, Tenet!
Thanks!
Quote:I'm curious: How did they come up with this formula for required protein needs?
There are a couple of places this information originally came from. The first, believe it or not, is veterinary medicine. Mostly for financial reasons, farmers needed to know what was the minimum amount of food to give their livestock to keep them from experiencing failure to thrive without overfeeding. This eventually led to more research into what specific components of the food were needed. Actually, most of what we know about nutrition needs (like vitamins and minerals too) came out of veterinary medicine.
The next layer of information came from simple studies looking at the nitrogen content of human urine. Carbohydrates and fats do not contain nitrogen. Only protein. So in looking at how much nitrogen is coming out of the body, we can calculate how much needs to go in to maintain nitrogen balance via protein.
Quote:Has anyone ever studied whether this might vary from person to person, other than based on activity level?
Oh, yes. There are tons of studies! Of course, they don't all agree, but I think it is safe to say that needs to vary from person to person, and from time to time. But for the most part, the research indicates situations where a person might require more than 0.8 grams of protein per kilogram body weight. For example, people who are trying to build muscle mass or lactating moms producing milk. If the body is in need of repair due to illness or injury, protein needs may also temporarily increase.
Sometimes if somebody has severe renal disease and is on dialysis, they will go below that amount, as the kidneys are responsible for filtering out the urea (nitrogen waste) from the blood.
As far as I am aware, hardly anybody argues against that protein needs are less than 0.8 g / kg. Those few sources which I have come across that do tend to be making emotional arguments, rather than intellectual ones and don't seem to have much of an understanding of biochemistry.
Even if a vegan ignored protein needs completely, and ate based on vitamin and mineral content alone, they would end up getting enough protein anyway because they would be eating plenty of nuts, seeds, and legumes.
Where people tend to get into trouble is when they conflate different approaches to diet and/or have a personality-type that is inherently mistrustful of people who are rationally-minded and instead trust whomever seems the most excited.
For example, the principle of a low-fat diet really has little bearing for somebody who is already eating little to no animal product. It is the animal fat which causes health problems. Plant fat (nuts, seeds, avocado, coconut) is a good thing, and omega-3s are absolutely necessary.
There is also some anti-bean misinformation floating around that talks about molecules called phytates present in them which interfere with mineral absorption. While phytates do interfere with mineral absorption, beans contain WAY more minerals than could possibly be interfered with by the phytates. Eating beans will definitely result in a net gain of minerals by the body. The misinformation occurs when some folks make the claim that eating phytates will somehow pull minerals out of the body, resulting in a loss. This is just not true. Now- soaking beans does cause some of the phytates to be broken down which could increase the bioavailability of the nutrients. But even unsoaked beans are a great food choice.
As one can see- if somebody is trying to go vegan, but also low-fat, and also avoids beans, they are probably going to get into some trouble nutritionally-speaking.
Quote:Also, has anyone ever studied how much assimilation factors into the equation? (ie. cooked rice and beans vs sprouted mung and sprouted oats, presumably having the same grams of protein and amino acid profile, but is ther a difference in assimilation because of cooked vs raw.)
For sure! But again, with mixed results. For example, consider this study:
Effect of soaking prior to cooking on the levels of phytate and tannin of the common bean (Phaseolus vulgaris, L.) and the protein value.
The researchers found that soaking the beans decreased the phytate content, but also decreased the protein digestibility. That's not what I would have guessed, personally. Also keep in mind that besides the factors intrinsic to the food that affect digestibility, there are factors that can vary widely from person to person in their body's digestive function. For example, pancreatic insufficiency (not enough digestive enzyme production), chronic inflammation, dysbiosis (gut microbe imbalance), or antacid use can all impair protein absorption from the gut.
So, unfortunately, these things tend to be difficult to control from a research standpoint because it is hard to isolate a single variable of protein content. However generally speaking, my intuitive sense is that sprouted and fermented veggies are the way to go.
There are good arguments on both sides of the raw vs. cooked debate so with respect to that I tend to stay in the middle with lightly steamed. It's definitely a poor choice to boil the heck out of one's vegetables, but there are some valid concerns about raw- especially in people whose digestive systems might already be compromised.
Then again, for the vast majority of people, simply eating more veggies, in whatever form, is going to be a vast improvement!
Quote:Also, you mention veggies. My understanding is that leafy greens have much higher protein content than other veggies, and a very favorable amino acid ratio. Humans just don't generally eat much of them, unlike gorillas who get a very high percentage of their protein from leafy greens.
EAT YOUR GREENS!
Dark leafy greens are indeed the most nutrient-dense food one could eat. I dunno why but many people seem to have some sort of mental block about these. (Mind control?)
Self: Eat more dark leafy greens!
Other: Oh I eat tons of romaine lettuce. I love Caesar salads!
Self: No- I am talking about dark leafy greens!
Other: Oh you mean like broccoli? I eat tons of that!
Self: I'm sorry, you are not understanding me. Broccoli is great, but I am talking about dark leafy greens.
Other: You mean baby spinach?
Self: Kind of. What I am talking about are DARK. LEAFY. GREENS. You know, like kale, collards, turnip greens, mustard greens, beet greens, or ANYTHING greens!
First and foremost, dark leafy greens are a great source of calcium. Something which even many dietitians seem to overlook due to being indoctrinated by the dairy association. Dark leafy greens are -also- a great source of magnesium. This is because magnesium is at the core of the chlorophyll molecule which plants use to capture energy from sunlight. Hence: more green = more magnesium. (Purple fruits tend to have magnesium as well, but for a different reason.) Incidentally, magnesium is also at the core of a molecule called CoQ10 which is essential for energy metabolism.
Calcium and magnesium work together as a pair in biological systems. (As do sodium and potassium.) Therefore, it stands to reason that consuming a lot of calcium without the corresponding magnesium (i.e. dairy products) is probably not the best idea.
Beans are also a great source of magnesium- two of the highest being the coffee bean and the cacao bean.
But anyway, back to protein. Yes, it is true that, compared to other vegetables, dark leafy greens have tend to have more protein. Problem is- there wasn't much to begin with.
Here is an example. This information comes from NutritionData which has great information on the nutrient content of foods. They even have a handy search tool where people can do a reverse search by nutrient, such as looking for foods which have the most calcium and magnesium.
OK. So according to this source:
1 cup of carrots = 1 gram of protein
1 cup of celery = 1 gram of protein
1 cup of kale = 2 grams of protein
As one can see- the kale indeed has TWICE as much protein as the carrots or celery. But it is still not very much.
Also, a cup of kale has 33 calories. That means the kale is 25% protein by calorie. But that statistic is misleading because there aren't that many calories in kale.
By contrast:
1 cup of peas = 8 grams of protein
1 cup of almonds = 30 grams of protein
1 cup of lentils = 50 grams of protein
Almonds and lentils are both 25% protein by weight. By calorie, almonds are 15% protein and lentils are 30% protein. See the difference?
By calorie, kale has more protein than almonds at 25%. By weight almonds have more protein than kale at 25%. But in the real world, most of us neither serve ourselves according to calorie, nor according to weight, but according to volume.
The reason so many people are confused about nutrient content of food is because we are using three different units of measurement- the calorie (energy), the gram (mass), and the cup (volume)- and people talk about them as if they were interchangeable concepts, which they are not.
On top of this, when some intellectual, rational, nerdy, "math whiz" type comes along one of these people, or their websites, they rapidly conclude that the speaker/writer doesn't know what they are talking about. And this is because... they don't. They are using words without knowing what they mean. They haven't actually looked up the definitions of the words they are using, and so they are speaking in babble. What is worse, they are "educating" others in this babble-speak, and thus adding to the confusion already present in their minds. As if it isn't bad enough with the dairy and corn associations crawling down our throats with propaganda at every opportunity. :-/
What is sometimes even worse than that- when faced with the actual truth about their comments, they tend to get butthurt, and react emotionally, rather than asking intelligent questions, just as you have done here. Then- when confronted by a "skeptic" these people tend to conclude that they must be a member of "the establishment" or a "disinformation agent".
Pretty ironic since these folks themselves are some of the biggest agents of disinformation, and play right into the hands of the establishment!
Quote:There is a movement towards more leafy greens via 'green smoothies' which can dramatically increase leafy green intake. I make a 'savory veggie stew' for lunch most days. It has as much greens as about 3 huge salads! With some added other veggies...all condensed into a single bowl of a very satisfying stew. I add hemp hearts too and I have no idea how many grams of protein it is, but wow, it's really filling and satisfying. I could never eat that much leafy greens otherwise.
That's great! We try to aim for 3 - 4 cups a day but it doesn't always happen. Thinking of creative ways to include greens, like in smoothies and soups as you mentioned, is a great approach!
Incidentally- when consuming raw or steamed greens, dressing them with 1 tablespoon of something oily (like olive or coconut oil) and 1 tablespoon of something acidic (like lemon juice or apple cider vinegar) will help to make the vitamins and minerals more bioavailable.
Quote:And, do you know why we need so much protein to build muscle?
Sure! Firstly, muscle tissue is 1/4 protein by weight. So the body needs 112 grams of protein just to make 1 pound of muscle tissue. Divide that over a week and it amounts to 16 extra grams of protein a day. But beyond that, there is an increased protein need because of the extra enzymes which need to be produced to actually build the muscle tissue, over and above the protein needed for the muscle tissue itself. And then there is even MORE protein needed to cover the additional energy expenditure that needs to be invested in exercise by the body as a whole in order to shift the hormones toward muscle-building.
So, all-in-all, for an "average" person to put on about a pound of muscle a week will take about an extra 30 grams of protein a day. Considering that the "average" person who isn't building muscle needs about 60 grams of protein a day, that comes out to around 150% of the normal protein intake, or approximately 1.2 grams of protein per kilogram body weight.
People who are "hardcore" bodybuilding will find their protein needs to be even higher- around 2.0 grams of protein per kilogram body weight.
Now, once that muscle is built, it WILL take more protein to maintain it. But luckily it isn't all that much. Doing the calculations reveals that it takes about an extra 0.3 grams of protein daily to maintain every extra pound of muscle.
Quote:In the ongoing protein debate, it's often pointed out that at the time in which we grow the most - as babies - and our organs and muscles are forming, our protein needs are actually very very low. Human milk has very low protein, comparatively. Any comments on that?
It's all relative, and numbers can be confusing. Even more confusing when there are so many out there that are more interested in spreading their agenda, rather than spreading truth. Check out this growth chart:
As we can see, from birth to about nine months, we should expect baby to put on about 1/2 kilo per month. That's about 1 pound. Keep in mind this is "on average".
Now the "rule of thumb" for feeding is about 2.5 ounces of milk daily per pound of baby. Breast milk has about 1/3 gram of protein per ounce.
So let's do the math:
Baby is born weighing 8.0 lbs and it feeds 20 ounces of milk per day. The 20 ounces of milk contains about 7 grams of protein. That's almost 2.0 grams / kg, which is in the "bodybuilder" range of protein intake.
At one month, baby now weighs 9.0 lbs and feeds 22.5 ounces of milk per day. The 22.5 ounces of milk contains about 7.5 grams of protein. Still in the "bodybuilder" range.
At two months: 10 lbs weight, 25 ounces milk, 8 grams protein. The ratio is going down, but still in muscle building range at 1.8 g / kg.
At three months: 11 lbs weight, 27.5 ounces milk, 9 grams protein. Still at 1.8 g / kg.
At six months, baby should be taking whole food in addition to breast milk. But even if they weren't, let's do the math: 15 lbs weight, 37.5 ounces milk, 12.5 grams protein. Still at 1.8 g / kg.
Cow's milk has about three times as much protein as human milk, or about 1 gram of protein per ounce. But then again, a newborn calf can be putting on a pound a day, rather than a pound a month. They also take a lot more milk!
Sometimes in the past when I have talked about these things I have remarked that some people just don't know what they are talking about. Perhaps that wasn't the best choice of words. But it doesn't make them any less true.
A lot of these people you are referring to that talk about how much protein greens have or how much protein babies supposedly don't need, are misinformed. They read facts and figures, and then falsely interpret them to fit according to their personal agendas and preconceived notions about what they want to believe.
If they would have actually taken the time to sit down, look a few things up on the Internet, and do some simple math on a calculator, they would see the truth for themselves quite plain as day.
It took me about an hour to put together all of the information you asked for in your last question. I took the time out of my day to do this because I actually care enough about babies to do this. And I don't even have kids!
Point being- I'm sure all these parents who are spreading misinformation would have a conniption fit were I to suggest that they didn't love and care for their babies more than any other parent on the planet. Now, I would never suggest such a thing. But I must wonder- what was really prohibiting them to take a single hour out of their lives to get the facts straight? Especially before spreading false knowledge to others?
One of those little mysteries of life, I guess. :-/
Now here is my question: Why is there, as you say, an ongoing protein "debate"? What is there to debate when the facts are well-established and easily demonstrable? Who is really benefiting from this debate? And why?