Wednesday, December 24, 2008

Protein Does a Brain Good


Humans were meant to be omnivores - our teeth are all the proof you need of this. But the body and brain need the protein part of the diet more than most people realize. So as you sit down to Christmas dinner tomorrow night, know that the turkey (or ham, or whatever) that you are eating is essential for your brain. [See below for an article on locally-grown beef.]
Brain Power: Why Proteins Are Smart

The brain's protein connection: How proteins keep the mind working smoothly, and properly.



Next to water, protein makes up most of the weight of our bodies. Muscles, organs, hair, nails and ligaments are all composed of protein, so it's obvious why protein is an important part of the diet.

But it gets more complex with the brain. The brain and its long spidery neurons are essentially made of fat, but they communicate with each other via proteins that we eat. The hormones and enzymes that cause chemical changes and control all body processes are made of proteins.

Have you ever noticed that a high carbohydrate lunch can make you feel sluggish? Or that eating protein in the middle of the day keeps you more alert through the afternoon? Brain cells communicate with one another via chemical messengers called neurotransmitters, which are usually made of amino acids, the building blocks of protein.

What you eat affects which nerve chemicals will be dominant in your brain, which affects how you feel. Carbohydrates can make you feel tired because they increase the brain's level of the amino acid tryptophan, which in turn spurs the brain to make the calming neurotransmitter serotonin. Serotonin is important for normal sleep patterns, learning, blood pressure and appetite, among many other functions.

Eating protein raises the levels of another amino acid called tyrosine, which prompts the brain to manufacture norepinephrine and dopamine, other kinds of chemical messengers in the brain. Not as well known as serotonin, norepinephrine and dopamine can keep you energized because they promote alertness and activity.

This isn't to say that to stay alert, you ought to eat mostly protein. A healthy brain produces hundreds of neurotransmitters needed for regular maintenance of the brain and needs proteins to do so. But the brain also needs carbohydrates for fuel and other nutrients for repair and maintenance of brain cells.

You don't need to load up on protein. Most Americans eat far more protein than they need and as a consequence end up consuming too much fat and cholesterol as well. The USDA recommends only two to three small servings of protein a day, or about 12 percent of total calories—and that's more than what most of the world consumes. Poultry, seafood and lean meat are the richest sources, as are dairy products, legumes, nuts and seeds. Grains and vegetables have protein too, albeit in lesser amounts but without the fat.

However, watching your diet isn't always enough. Some neurotransmitters, like dopamine, essential to feelings of pleasure and reward, are also depleted by stress and a lack of sleep. Alcohol, caffeine and sugar all appear to lessen the effects of some neurotransmitters in the brain. In addition to a healthy, varied diet, the brain also needs healthy everyday living habits.

[Psyched for Success, 3 January 2003]
OK, good information, except that the USDA recommendation for protein is the minimum needed for health, not what is needed for optimal health.

Ideally, we should be eating a gram of complete proteins (meat, fish, dairy products) per pound of body weight. The protein makes us feel more full, produces chemicals that help us burn fat for energy, and repairs the muscles after weight training (which we all should be doing). And if your protein is from lean sources (low-fat cottage cheese, chicken, turkey, fish) then you don't get the health risks the USDA warns about.

Finally, some of us are trying to eat meat that is environmentally friendly and treated humanely before it comes to our plate. So here is an article that talks about how to get healthy beef. Even if you don't care that the animals get to live as they were meant to live (grazing for grass), the health benefits of the higher levels of omega-3 fats can actually make beef a healthy choice for one's protein intake.
Nature's Bounty: Back-to-Basic Beef

Ask not what there is to eat for dinner—but what your dinner ate for dinner.

By: Daniel A. Marano

Beef, it's what's for dinner, has long been the motto of the National Cattlemen's Beef Association. But if you eat meat, what matters more is, what did your beef have for dinner?

At local farmers' markets all over the country and on their own Web sites, a growing number of small-scale, independent ranchers are offering pasture-raised beef directly to increasingly nutrition- and taste-conscious consumers. Propagating a literal grass-roots movement around healthier meat and more sustainable environmental practices, some beef ranchers even refer to themselves as "grass farmers," since the quality and upkeep of pasture plays a critical role in the health of the herd and the flavor and nutrition of the meat they sell.

Grass-fed beef, particularly from cattle that forage for their own living food, has high levels of the fat-soluble vitamins A and E and of omega-3 polyunsaturated fats. Pasture beef is leaner overall with up to three times more omega-3s than conventional beef briskly bulked-up on soy and corn in huge feedlots. Pasture-fed beef also has a much better ratio of omega-3s to omegas-6s, a balance critical to human health, providing anti-inflammatory and neuroprotective effects.

The health-aware practices of grass farmers are anything but new: They recall the food and farms that prevailed until a generation or two ago, before agriculture was consumed with chemical enhancement and corn- and soy-feed production. However, their talk is new; whether behind a market stand or on a Web site, these ranchers often speak in terms more associated with nutritionists or neuroscientists, citing good fats, bad fats, and the value of antioxidants.

They are also conversant with Michael Pollan's 2006 book The Omnivore's Dilemma, which spotlights Virginia farmer Joel Salatin, who sees his cattle grazing as if living at a giant salad bar. Most of the new breed of ranchers raise heritage breeds in small herds—but they get the big picture about the relationship between healthy animals, plants, and soil. Allowed to roam in open pasture, their animals do not require constant worming and antibiotics to resist disease.

Due to the vastly healthier fat distribution and fatty acid composition of grass-fed beef, it both cooks and tastes different from commercial beef. It even has a different odor. "Studies indicate that 15 to 20 percent of consumers prefer the flavor of grass-fed beef in blind tests," reports John Comerford, associate professor of animal science at Penn State, who works with ranchers to develop best practices. As for the other 80 percent who prefer the flavor of commercial beef, he isn't sure whether it's "an acquired taste, or something else. It's hard to tell."

Here in Michigan, I sought out John McLaughlin of McLaughlin Farm by way of LocalHarvest.org. He raises Scottish Highland cattle on a former dairy farm his grandparents bought in 1932, and practices rotational grazing on a variety of grasses and living greens. He dry-ages his beef, as butchers used to do, to bring out the flavor. Many of his customers tell him the same thing: "This meat reminds me of the meat I had as a child."

Like many cattlemen with a presence on LocalHarvest, McLaughlin cultivates a direct relationship with his customers. He produces a newsletter and heaps beef-buyers with recipes and advice on how to cook his lean beef—"low and slow," since it can't stand up to the high temperatures that wet-packaged supermarket beef can. McLaughlin admits that he has to do a lot of education before that first sale, but these days, there is a wait list for his meat several months out.

[Psychology Today Magazine, Nov/Dec 2008]
Eat Wild has a directory of more than 800 local grass-fed farms where you can get your own healthy beef.


2 comments:

Anonymous said...

I think it's important to differentiate between an optimal diet for an athletic, muscle-building Westerner (a vanity in most parts of the word) and what is truly necessary to live.

I eat at least 1 gram of protein per pound because I want to fuel hard workouts, but I have to admit I struggle with whether it's in any way justifiable because it's certainly not a sustainable way for the vast majority of the world to live -- and I've lived with perfectly happy, wonderful people in the undeveloped world who have the luxury of only VERY limited protein (people who are also quite lean because they eat no food to excess.)

Additionally, my parents are low-protein, low-calorie eating vegetarians and are shockingly healthy and spry in their 70s. Most of the scientific evidence on longevity comes down on the side of that kind of diet. See http://www.newscientist.com/article/dn7442

I say all this even though I enjoy the results personally of eating a higher protein diet and know that it helps some with weight loss. I just think we should be honest that a) the science isn't there to say it's optimal for longevity and b) it's unsustainable on a planetary scale.

william harryman said...

Hey TY,

I agree with what you say - my diet is not even possible for 3/4 of the world's population.

While the longevity debate (so far) comes down in favor of a meatless diet, no one has done a longitudinal study of people who eat the way I do, and maybe you do (fresh, organic fruits and veggies, lean protein, healthy nuts, etc). Add in resveratrol, which acts like calorie restriction in the body, and we might actually outlive vegetarians, who suffer a variety of illnesses from amino acid deficiencies.

I do believe it's actually possible to increase the protein intake in third world countries w/out meat (plumy nut). Studies have shown that a 15-25% increase in protein intake (still less than a gram per pound) makes a 25-50 point difference in the IQ of children. That's huge. It also strengthens the immune system.

All that said, I do agree with what you said.

Peace,
Bill