Monthly Archives: January 2011

About Green Tea

Posted by on January 30, 2011 77 comments

Erich asked what kind of tea we drink. Tea is a subject dear to our hearts, so we thought we’d discuss it today.

First, some background. Over at Planet Tea they have a useful flowchart describing how different kinds of tea are made:

The critical step is fermentation, which oxidizes the leaf and turns it black. Green tea is unfermented; oolong (wu long) is partially fermented; and black tea (in Asia, “red tea”) is highly fermented. Black tea has a longer shelf life than green tea.

Growing region matters. Mainland China is by far the world’s largest producer of tea, but China is extremely polluted and we would not trust Chinese tea. Japan and Taiwan both produce excellent green teas; we drink tea from both countries.

Taiwanese Tea

The Taiwanese teas with the highest reputation are “high mountain tea”; these are grown at high altitudes above the smog. We drink both green and oolong high mountain teas from Taiwan. Ours come in 300 g vacuum-packed packages:

The one on the left is green tea, the one on the right an oolong; both are “high mountain” teas. Each package weighs 300 g. We use about 4 g (20 leaves) of tea per day, and so a package lasts about 3 months. A single 300 g package of high quality tea may cost $100, so the total cost is about $1 per day; but multiple cups of tea may be obtained from each day’s tea.

The leaves are rolled and dried during processing, and shrivel to a very small size, then re-expand when placed in warm water. Here is what they look like:

Left — rolled and dried leaves, ready to make tea. Right — an opened bud, after being used.

The opened bud on the right gives you a good idea what the leaves look like on the tea tree. Workers pluck these small buds from the trees and place them in baskets; the finest buds are plucked early in the spring.

Aside: Some Equipment

For best results it’s important to use pure water. Tap water produces a discolored tea with a foul taste. We get good results filtering our water in a Britta filter. In fact, we judge that it’s time to change the filter when our tea changes taste. The Britta instructions recommend changing the filter every two months, but we find it needs to be changed every month if our tea is to retain its flavor.

If you make tea often, it’s helpful to have a hot water dispenser, like this one from Zojirushi, along with your Britta filter:

Tea is best when the leaves have steeped for about 5 minutes. Since you may take much longer to drink the tea, it’s important to steep the tea in a separate container from your drinking mug. Here’s what we use:

Left — An Asian “busy person’s” tea-pot. A container at top holds the tea leaves and enough water to make a single cup. When the leaves are done steeping, pressing the red button drains the water into the pot, after which it can be poured into a mug. Right — an airtight container we use to store our tea leaves.

Alternatively, Asian supermarkets sell teacups in 3 parts — a mug, a container to hold the tea leaves, and a lid to cover while the tea is steeping. They look like this:

The tea leaves go in the removable upper part; when it is removed the tea drains through the holes in the bottom into the mug. After drinking a cup, the upper container with the leaves can be put back in and more hot water added to steep another cup.

Making the Tea

To make the tea, place 15-20 rolled buds into the leaf container, and add hot (near boiling) water. Taiwanese green tea typically requires 3 to 5 minutes to steep, and the tea is actually yellow, not green.

Shou-Ching likes her tea prepared the classic way. Add hot water to new leaves, and drain it after 30 seconds as the leaves just begin to open; this is thought to clean any impurities. Then add new hot water, let it steep 3 to 5 minutes, and drink this second batch. This produces a delicate, light yellow tea. Paul lets his steep a bit longer to make a slightly darker tea and adds a lemon slice. Here is what they look like:

Japanese Green Tea

Japanese green tea is made with a different process; the tea leaves are usually crumbled, not rolled. Here is what they look like:

These crumbled tea fragments are placed directly in the teacup and produce a green-colored tea. Yes, the tea leaves can be swallowed. Here is a comparison of a cup of Japanese green tea (left) with a Taiwanese green tea (right):

Obtaining Fine Teas

We are regularly sent tea by relatives and friends in Asia, so we haven’t had to shop for tea in the US.

However, Google searches turn up a number of vendors. “Tea from Taiwan” has some good-looking teas. Reader Gary Wilson kindly wrote to recommend Upton Tea Imports. And here are some Amazon links, not all currently available:

At roughly $1 per day, fine tea is not inexpensive. However, many people spend as much or more on coffee. Paul makes 5 or 6 cups per day from a single 4 g set of leaves, so the cost averages to only $0.20 per cup.

If your only knowledge of tea is derived from the Lipton Tea Company, we very much recommend that you give fine green or oolong teas a try! You might find tea more pleasant and enjoyable than you imagined.

Alien Dance Partner Syndrome

Posted by on January 29, 2011 7 comments

Dr. Michael Mosley of the BBC reports, Alien Hand Syndrome sees woman attacked by her own hand:

55-year-old Karen Byrne in New Jersey … suffers from Alien Hand Syndrome.

Her left hand, and occasionally her left leg, behaves as if it were under the control of an alien intelligence.

I thought that condition must be very rare, but then I saw that it also afflicts Russian dancers (Inga Savitskaya, Moscow 2004):

Low-Protein Leanness, Melanesians, and Hara Hachi Bu

Posted by on January 27, 2011 71 comments

Gunther gatherer raised an interesting issue in a comment to Tuesday’s post.  Protein may be satiating in the short run; but what about the long run?

[H]igh protein keeps you full at first. But no one really knows for how long. Eventually it stops working and you find you’re eating a lot ON TOP of all the high protein you were already eating. All of us here tried Atkins long ago and fell off the bandwagon more than enough times to know it gets boring, stops working against hunger and doesn’t keep the fat off forever.

I agree. This is why we recommend a version of the normal Perfect Health Diet, which is normal — not high — in protein, for weight loss. Our diet isn’t the quickest way to lose weight, but we think it is likely to work best in the long run.

The Long-Term Effects of High-Protein Diets

I argued in Tuesday’s post that the satiating effects of protein had to be temporary, and that in the long run higher protein might cause, not reduced appetite, but only a slight change toward a leaner body composition.

A more interesting question is:  could high-protein diets be positively harmful?

Maybe!  Studies in both animals and humans indicate that eating high protein during childhood creates a predisposition for obesity in later life.

For instance, rats raised on a high-protein diet in childhood are more likely to become obese when given calorie-rich (sugar and fat) diets in adulthood. [1] The researchers conclude:

Our research demonstrating a significant susceptibility to an obese phenotype in rats weaned onto a high-protein diet and then challenged in adulthood with a high-fat high-sucrose diet suggests that lasting changes result from altering the composition of the first solid food that is consumed throughout growth into early adulthood. While all rats in this study consumed the same high energy diet during the last 6 weeks of the intervention, distinct metabolic profiles remained evident from exposure to the different diets during growth. This would suggest that these changes, either long-lasting or perhaps permanent, ultimately influenced the adiposity response of these rats to a high energy challenge in adulthood. Overall, it appears that a long-term diet high in protein, when mismatched with a high energy challenge, has negative effects on body mass and hormones and genes involved in glucose and lipid metabolism. [1]

The same phenomenon occurs in humans. In the book we mentioned a study showing that slightly higher protein level in infant formula – 9% protein vs 7% normally – caused children to become overweight two years later. [2]

So parents, let your kids follow their taste buds to high-carb, high-fat diets!

Might adult high protein diets promote later-life obesity too? I’m not aware of evidence, but I don’t think the possibility can be ruled out. I will look for evidence when I do research for two future blog series: one on protein intake, aging, and longevity; the other on connections between obesity and the human aging program.

Can You Be Lean on a Low-Protein Diet?

Tuesday’s post cited research indicating that we have a set point for protein intake: humans are genetically programmed to seek around 360 protein calories per day, and appetite becomes satiated once that is achieved.

But if protein intake determines appetite, then it seems those eating a low-protein diet face a Hobson’s choice:

  • If total calories are not increased, then the low protein dieter can expect to have a chronically unsatisfied appetite.
  • If total calories are increased, so that appetite is satisfied, then the low protein dieter can expect a higher equilibrium weight and a slightly less lean body.

Is it possible, then, to restrict protein, eat mostly carbs and fat which we know are the ingredients of appetizing desserts – and still achieve a lean healthy body, and feel comfortable? 

Yes, I believe so.

Melanesians Do It

Gunther pointed out that Melanesians are lean and long-lived on low protein diets:

I think it would be a bit fairer to include some consideration and explanation of Melanesians and their extremely low protein diet (anywhere from 10% to only 3% protein daily). Their extremely high level fitness and body composition flies in the face of all of these high protein studies.

It’s true: Kitavans, Tokelauans, and other Melanesians eat high-carb and low-protein, yet they’re noted for “extreme leanness.” [3] Why?

Well, first of all, the Melanesian islander diet is a variant of the Perfect Health Diet:  it is entirely free of food toxins. As I argued last week, eliminating toxins is the key to healthy weight regulation. But there are other factors.

Coconut Oil

The most abundant fatty acid in the diets of Kitavans and Tokelauans is lauric acid, the 12-carbon fatty acid which is the predominant fatty acid in coconut oil. [4, 5] These shorter-chain fatty acids are ketogenic and have significant effects on the body: for instance, they raise HDL levels. They also make people lean.

In one study, 8 weeks taking 1 tbsp per day coconut oil caused a significant decrease in body weight, waist size, and blood triglycerides. [6] In another, obese women who received 2 tbsp (30 ml) coconut oil per day slimmed their waist and increased HDL without an increase in LDL, while a comparison group receiving soybean oil did not slim their waist and had lower HDL with higher LDL and total cholesterol. [7]

Resistant Starch

Another feature of the Melanesian diet is that the biggest share of calories came from “safe starches” like yams, sweet potatoes, and sago.

These foods have a lot of fiber in the form of “resistant starch.” Digestion of resistant starch by colonic bacteria produces a lot of butyrate, a short-chain fatty acid that strongly promotes leanness.

For example, butyrate improves insulin sensitivity and prevents rats from becoming obese. [8]

Hara Hachi Bu

But the most reliable strategy seems to have been worked out by Asian and Pacific cultures long ago, many thousands of years ago.

The key is that if the diet is well nourishing, then appetite will be mild and easy to consciously control. What will be experienced is not hunger, which indicates malnourishment, but a mild desire for food that can easily be ignored.

There is an ancient Chinese saying:

“Eat until you are eight-tenths full, walk 100 steps after meals, live 99 years.”

In Japanese the saying is Hara Hachi Bu, eat until eight-tenths full. Hara Hachi Bu is common practice in Okinawa, where it helped produce the world’s most long-lived population.

As we note in the book, the traditional Okinawan diet is extremely close to the Perfect Health Diet: the Okinawan diet was rich in safe starches and animal fats, and near the low end of our recommended protein range: Okinawans ate about 300 g (2/3 pound) meat and fish per day.

The key here is that on a low-protein diet, eating until eight-tenths full is not a calorie-restricted diet. It is a calorie-sufficient diet that isn’t quite satiating because it is low in protein.

Intermittent fasting is a helpful part of Hara Hachi Bu. Eating only within a relatively short window each day makes it easy to keep calories down.

My Experience

I have been practicing protein restriction for several years, eating coconut oil and safe starches for several years, and practicing daily intermittent fasting for over six months. I drink tea or lemon-flavored water through the morning, and on most days eat only between 2 pm and 8 pm. If I snack during the fast it is usually either a piece of dark chocolate or some coconut oil.

I sometimes go many days eating relatively little, then eat a lot for a few days. Physical activity – sports, intense exercise, running – increases my appetite noticeably. Regardless, I never feel hungry. It is easy to complete the daily fast: some tea, sometimes with coconut oil or dark chocolate, is enough. I now do total fasting on religious fast days – for instance, I now do a 64-hour fast from Holy Thursday through Easter Sunday morning. Generally, as soon as I focus my attention on work I forget that I wanted food.

(This is a very good sign for my health, by the way. During my long chronic illness I couldn’t tolerate fasting at all.)

I haven’t noticed difficulty adding muscle when I work out. I believe I would add muscle more easily on a higher-protein diet, but as it is I add muscle more easily than I used to on the standard American diet. I’m content with my body composition.

Conclusion

I am convinced that by eating coconut oil, getting carbs from safe starches, and practicing intermittent fasting and Hara Hachi Bu, most people can become well-muscled and lean on a low-protein diet without any sense of hardship.

Since a carb-fat mix is the classic recipe for dessert, this makes for an extremely tasty diet.

If you want the surest way to lose weight over the next few days, eat a high-protein diet. But if you want a long-term diet that maximizes longevity by restricting protein, consider eating a tablespoon or two of coconut oil per day, fasting for 16 hours a day, and finishing your meal eight-tenths full.  

If you walk a hundred steps after dinner, you just might become a healthy centenarian!

References

[1] Maurer AD et al. Consumption of diets high in prebiotic fiber or protein during growth influences the response to a high fat and sucrose diet in adulthood in rats. Nutr Metab (Lond). 2010 Sep 29;7:77. http://pmid.us/20920272.

[2] European Childhood Obesity Trial Study Group. Lower protein in infant formula is associated with lower weight up to age 2 y: a randomized clinical trial. Am J Clin Nutr. 2009 Jun;89(6):1836-45. http://pmid.us/19386747.

[3] Lindeberg S et al. Haemostatic variables in Pacific Islanders apparently free from stroke and ischaemic heart disease–the Kitava Study. Thromb Haemost. 1997 Jan;77(1):94-8. http://pmid.us/9031456.

[4] Lindeberg S et al. Lipoprotein composition and serum cholesterol ester fatty acids in nonwesternized Melanesians. Lipids. 1996 Feb;31(2):153-8. http://pmid.us/8835402.

[5] Lindeberg S, Vessby B. Fatty acid composition of cholesterol esters and serum tocopherols in Melanesians apparently free from cardiovascular disease – the Kitava study. Nutr Metab Cardiovasc Dis. 1995; 5: 45-53.

[6] Xue C et al. Consumption of medium- and long-chain triacylglycerols decreases body fat and blood triglyceride in Chinese hypertriglyceridemic subjects. Eur J Clin Nutr. 2009 Jul;63(7):879-86. http://pmid.us/19156155.

[7] Assunção ML et al. Effects of dietary coconut oil on the biochemical and anthropometric profiles of women presenting abdominal obesity.  Lipids. 2009 Jul;44(7):593-601. http://pmid.us/19437058.

[8] Gao Z et al. Butyrate improves insulin sensitivity and increases energy expenditure in mice. Diabetes. 2009 Jul;58(7):1509-17. http://pmid.us/19366864.

Protein, Satiety, and Body Composition

Posted by on January 25, 2011 62 comments

A number of studies have found protein to be the most satiating macronutrient, with fat moderately satiating, and carbs least satiating.

Thus, when people reduce carbs and increase protein, their appetite declines and they almost always reduce calorie intake. This can leads to rapid short-term weight loss. This is why most popular weight loss diets are high in protein: increasing protein causes dieters to quickly lose some weight, encouraging them to continue.

A 2005 editorial in the American Journal of Clinical Nutrition summarized the evidence that higher protein intake is helpful for weight loss:

The higher than usually recommended protein content of many popular diets, such as the Atkins Diet, The Zone, and The South Beach Diet, seems to point at possible solutions to the obesity epidemic. Many national dietary guidelines have, until recently, recommended that only 10–20% of the calorie content of the diet come from protein; however, 30–40% of the calorie content in the aforementioned diets comes from protein, at the expense of carbohydrates. Newer research indicates that the high-protein content of these diets may actually be the reason for their partial success in inducing weight loss, despite no restrictions in total calories (2)….

In this issue of the Journal, Weigle et al (3) showed that an increase in dietary protein from 15% to 30% of energy and a reduction in fat from 35% to 20%, at a constant carbohydrate intake, produces a sustained decrease in ad libitum calorie intake and results in significant weight loss….

Weigle et al’s results clearly showed that protein is more satiating than is fat, and previous studies have shown that protein is more satiating than is carbohydrate (4). Moreover, diets with a fat content fixed at 30% of calories produce more weight loss when high in protein (25% of energy) than when normal in protein (12% of energy): 9.4 compared with 5.9 kg after 6 mo; after 1 y, evidence was found to suggest that the high-protein diet, independent of the loss of total body fat, resulted in a significant loss of visceral fat (5). [1]

But there are downsides to high protein consumption. Various animal experiments have found that longevity is increased with protein restriction. Also, protein restriction promotes autophagy, which enhances immunity to intracellular bacteria and viruses. So higher protein intake may shorten lifespan and increase the risk of disease.

In a post on his blog (linked in this comment), Dennis Mangan introduced us to the “protein leverage hypothesis.” This hypothesis is put forward in a 2005 paper by SJ Simpson of Oxford University and D Raubenheimer of the University of Auckland [2].

The Satiating Power of Protein

The paper has some graphs which neatly illustrate the satiating power of protein. When animals are given a food formula with a lower protein fraction, they eat more total calories.

Here are some data from rats (b) and chickens (c). The numbers are in kiloJoules; divide by 4.18 to get calories. The animals were on feed formulas with a constant fat content, but different carb-protein ratios. Each data point represents a diet with a different P:C ratio.

If both macronutrients were equally satiating, then the animals would eat the same amount of calories regardless of their food’s protein-carb ratio. The data points would fall on a 45º line (say, for chickens, a constant 1000-kJ line connecting the 1000 kJ mark on the y-axis with the 1000 kJ mark on the x-axis).

But they don’t:  if a line were fitted to these points, it would be much closer to vertical than 45º. The rats, for instance, eat around 150 kJ protein and 75 kJ carb if given high-protein food, but 75kJ protein and 300 KJ carb if given high-carb food. That’s 225 kJ (54 calories) on a high-protein diet, but 375 kJ (90 calories) on a high-carb diet.

The chickens and rats act like protein dominates appetite control:

  • A shortage of protein makes them hungry, and it takes a lot of carbohydrate to satisfy that hunger. So they eat a calorie excess.
  • An excess of protein satisfies their hunger and causes them to quit eating while they are still in calorie deficit.

Evidence in Humans

The same sort of thing happens in humans:

Results a, b, and c are from “short-term” experiments that varied from 2 days to 6 months in length. Results d, e, f, and g are from “long-term” experiments.

People tend to gravitate toward a protein intake of 1520 kJ (360 calories). This can be construed as the “normal” human protein intake, and tends to occur near a carb+fat intake of 8000 kJ (1900 calories). So the “normal” protein fraction of the diet is 360/2260 or 16%. This is consistent with epidemiological data, which finds that nearly everyone worldwide eats near 15% protein.

A line fit to the data has the same steep slope as the animal experiments, but note something interesting. The short-term experiments have a very steep slope, but the long-term experiments have a slope much closer to 45º.

This has to happen. Otherwise, a high-protein diet would lead to permanent calorie deficit which, over time, would lead to starvation. A low-protein diet would lead to permanent calorie excess which, over time, would lead to obesity.

Since we know people neither starve nor become obese due to small adjustments in protein fraction, they must adjust their calorie intake. In the long run, protein no longer controls calorie intake. So there is great protein leverage in the short-term, but much less protein leverage in the long term.

Simpson and Raubenheimer try to develop protein leverage into a theory of obesity. It’s not a very good theory, so I’ve relegated it to an appendix.

Instead, I’d like to talk about what this satiating power of protein means for Perfect Health Dieters.

Implications for Perfect Health Dieters

We have a fairly broad healthy protein range, 200 to 600 calories per day, which brackets the “normal” protein intake of 360 calories. What happens if you shift from 360 calories protein to either the low-protein or high-protein ends of the range?

IF YOU REDUCE PROTEIN: 

At low-protein intake, your appetite goes up and total calories go up. You gain a little weight, in the form of adipose mass. This causes leptin levels to increase. As we discussed in “How Does a Cell Avoid Obesity?”, higher leptin (a) lowers appetite and (b) increases thermogenesis, or destruction of fat as waste heat.

Adipose mass increases until the actions of leptin counterbalance the influence of protein leverage.

You reach equilibrium at a slightly higher fat mass and slightly higher leptin levels than on the “normal” protein intake.

IF YOU INCREASE PROTEIN:

At high protein intake, appetite goes down and total calories decrease. You start to lose adipose mass. This causes leptin levels to go down. This (a) increases appetite and (b) decreases thermogenesis, or heat generation.

Adipose mass decreases until a new equilibrium is reached. Equilibrium is reached at a slightly lower weight and slightly lower leptin than on the “normal” protein intake.

IN SHORT:

The main effect of changing the protein content of the diet is a modest change in body composition.

  • High-protein diets make you leaner and a little lighter.
  • Low-protein diets give you a slightly higher adipose reserve and make you slightly heavier.

The effect is probably small; probably just a few pounds either way. But if you’re looking for to win a bodybuilding competition and you have to become extremely lean and “cut,” you’d do well to adopt a high-protein diet.

It’s probably not a surprise, then, that people with the leanest bodies tend to be healthy but high-protein dieters. Here’s a picture of Anthony Colpo:

I think Anthony has a healthy body, but I don’t think you need to be this lean to be healthy. He would be equally healthy with a few more pounds of adipose tissue.

Conclusion

In the book we say that higher protein intake makes it easier to add muscle, and thus that it may be favored by athletes. Based on today’s post, we can adduce two other reasons to eat a high protein diet:

  1. A more chiseled body. If you want a lean, “cut” look, like Anthony Colpo, high protein will help.
  2. A controlled appetite. In a recent post, Don Matesz stated that he liked a high-protein diet because it helped him auto-regulate his calorie intake. If your goal is “effortless” (willpower-less) calorie restriction, then high protein may help – at least for a while.

However, there are reasons to restrict protein as well. Lower protein intake is likely to extend lifespan, and can increase immunity against intracellular bacteria and viruses, which are behind many late-life diseases.

Is it possible to achieve a lean, muscular body while still gaining the longevity and immunity advantages of low protein intake? And can one lose weight comfortably without assistance from a high-protein diet?  Those will be the topics of Thursday’s post.

References

[1] Astrup A. The satiating power of protein—a key to obesity prevention? Am J Clin Nutr. 2005 Jul;82(1):1-2. http://pmid.us/16002791.

[2] Simpson SJ, Raubenheimer D. Obesity: the protein leverage hypothesis. Obes Rev. 2005 May;6(2):133-42. http://pmid.us/15836464.

Appendix: The Protein Leverage Hypothesis as a Theory of Obesity

To the satiating power of protein, the protein leverage hypothesis adds two premises:

  1. That any increase in total calorie consumption leads to weight gain which induces insulin resistance in the liver, which in turn upregulates gluconeogenesis. Contrariwise, any decrease in calorie consumption reverses insulin resistance in the liver and downregulates gluconeogenesis.
  2. That the loss of protein associated with gluconeogenesis is treated by the brain’s appetite control centers exactly the same as a decreased intake of protein, and therefore that ongoing gluconeogenesis increases appetite immensely.

The theory of obesity is that once someone starts eating a low-protein diet, their appetite goes up. So they eat a larger amount of total calories, and gain weight. The weight gain causes them to become insulin resistant in the liver. Once that occurs gluconeogenesis is no longer inhibited by insulin, and the liver converts protein to glucose willy-nilly. The loss of protein stimulates appetite. But the person has to eat a lot of excess calories to get enough protein to replace the protein lost in gluconeogenesis. So weight goes up even more. There is a vicious spiral.

If these premises were correct, then:

  • Weight would be unstable. Weight would spiral out of control upward if people ate low-protein diets, and people would wither away once they started eating high-protein diets.
  • Low-carb diets would be extremely obesogenic. Every 1 calorie reduction in carb intake below the body’s daily needs of 600 calories would induce the eating of an extra 1 calorie of protein for purposes of gluconeoegenesis, and on the order of 4 extra calories of fat (by the leverage hypothesis: the P:F ratio stays constant). So each reduction of carb intake by 1 calorie leads to an extra ~5 P+F calories and an increase in total energy intake of 4 calories. Zero-carb diets would induce ravenous appetite, consumption of an extra 3,000 calories per day above the amount needed for weight stability, and obesity and metabolic syndrome would rapidly follow.

Neither is the case.